Questa ricerca è gratitudine intrapresa con il sostegno della Ingegneria e Scienze Fisiche Research Council (EPSRC), finanziato attraverso una borsa di formazione dottorale. Open Access spese di produzione articolo (APC) sono stati finanziati da Research Councils UK (RCUK). Tutti i dati sono forniti integralmente nella sezione dei risultati della carta. I risultati rappresentativi sono stati precedentemente pubblicati dagli autori 42. Vorremmo ringraziare il Dott Senthilarasu Sundaram presso l&#39;Università di Exeter per il suo aiuto nella caratterizzazione delle prestazioni elettriche delle cellule.

1. formulazione dell&#39;inchiostro Nota: le formulazioni di inchiostro sono spesso tenuti segreti altamente sorvegliato dai produttori. Il successo formulazioni equilibrio getto, goccia formazione, bagnatura e il comportamento di essiccazione al fianco di prestazioni funzionali. Solitamente un materiale funzionale viene dispersa in un solvente ed almeno un altro componente per renderli Jettable. Questa sezione descrive lo sviluppo di un TiO2 inchiostro per un uso all&#39;interno di stampa a getto d&#39;inchiostro. Un piccolo lotto di inchiostro è stato preparato con il metodo seguente. Attenzione: la preparazione di inchiostro deve essere effettuata in una zona adeguatamente ventilato, per esempio, sotto una cappa aspirante, mentre indossa occhiali protettivi occhi e guanti in lattice. <ol><li> Preparare una soluzione acquosa 0,1 mM di acido cloridrico (HCl) per produrre un pH di circa 4. </li><li> Aggiungere 32 g della soluzione di acido per 8 g di un solvente compatibile con un punto di ebollizione più alto e più basso tensione superficiale dell&#39;acqua (quale dimetilformammide (DMF)). L&#39;aggiunta di un co-solvagisce ent come agente essiccante per indurre un flusso che circola all&#39;interno della gocciolina inchiostro evapora inchiostro, portando a un inserimento uniforme nanoparticelle sulla superficie della goccia 21. </li><li> Aggiungere 1,5 g di disperdente (45% soluzione attiva di glicole propilenico e tetrametil-5-decyne-4,7-diolo in acqua). </li><li> Aggiungere 10 g di glicole etilenico, come un umettante per evitare l&#39;essiccazione in corrispondenza degli ugelli. </li><li> Aggiungere 0,5 g di agente antischiuma (20% soluzione attiva di diolo acetilenico in methoxypolyethyleneglycol) per l&#39;inchiostro per evitare bolle d&#39;aria da sviluppare. </li><li> Eseguire un semplice test shake prendendo una aliquota dell&#39;inchiostro in un contenitore chiuso e agitare manualmente per 60 sec. Se si osserva la schiuma quindi aggiungere altri 0,5 g di antischiuma agente all&#39;inchiostro. </li><li> Mescolare la soluzione per 8 ore utilizzando una barra di agitazione magnetica per garantire l&#39;omogeneità a temperatura ambiente. </li><li> Aggiungere 1,5 g di biossido di titanio (TiO 2) nanoparticelle con una dimensione delle particelle primarie di 21 nm e la superficie di35 - 65 m 2 / g. </li><li> Sonicare miscela utilizzando una sonda ad ultrasuoni per 15 minuti ad una frequenza di 60 Hz. </li><li> Misurare le dimensioni delle particelle, utilizzando una tecnica di valutazione appropriato come dispersione della luce dinamica (DLS) secondo il protocollo del produttore, per garantire che essi scorrere facilmente attraverso le aperture degli ugelli. Effettuare misurazioni alle stesse condizioni (ad es., Lo stesso solvente, pH, concentrazione di disperdente) da utilizzare per l&#39;inchiostro da ciascun componente può influenzare la formazione di agglomerati all&#39;interno dell&#39;inchiostro. Per getto di successo, le particelle all&#39;interno del liquido deve essere 100 volte più piccola l&#39;apertura dell&#39;ugello. </li><li> Misurare la viscosità dell&#39;inchiostro, utilizzando una tecnica di valutazione appropriato come un viscosimetro rotazionale secondo il protocollo del produttore, per garantire getto affidabile dalla testina di stampa come stampa a getto di inchiostro richiede inchiostri a bassa viscosità compresa tra 2 e 20 centipoise (cP). Aumentare la viscosità attraverso la additisu materiali polimerici o materiali a base di cellulosa; tuttavia questi devono essere rimossi dopo la deposizione per liberare i siti per il colorante all&#39;interno del film stampato 22. </li><li> Misurare la tensione superficiale dell&#39;inchiostro, utilizzando una tecnica di valutazione appropriato come un tensiometro secondo il protocollo del produttore, per garantire getto affidabile. Le linee guida formulazione fluida Jettable per le stampanti a getto d&#39;inchiostro suggeriscono una tensione superficiale tra 28 e 33 mN / m per abilitare la stampa affidabile. </li></ol> La stampa a getto d&#39;inchiostro 2. <ol><li> Prima di stampare, immergere i substrati di vetro in una soluzione al 2% in peso di detersivo pulizia (una miscela di tensioattivi anionici e tensioattivi non ionici agenti attivi, agenti, alcali, costruttori detergenti non-fosfati e agenti sequestranti stabilizzanti, in base acquosa) in acqua deionizzata. Risciacquare accuratamente il bicchiere con acqua deionizzata non appena vengono rimossi dalla soluzione di pulizia per rimuovere tracce di contaminazione e detergente. </li&gt; <li> Misurare l&#39;energia superficiale del substrato, utilizzando una tecnica di valutazione appropriato come un tensiometro secondo il protocollo del produttore. Per una buona adesione, l&#39;energia superficiale del substrato non deve superare la tensione superficiale del liquido di oltre 10 - 15 mN / m. Modificare l&#39;energia superficiale del substrato utilizzando metodi come trattamento corona 23, il trattamento al plasma 24 e attacco chimico 25 se non è adatto. </li><li> Caricare il substrato nella stampante secondo il protocollo del produttore. </li><li> Lavare la testina di stampa con l&#39;inchiostro attraverso la porta situata sul lato della testa di spostare qualsiasi soluzione di aria o di pulizia all&#39;interno del serbatoio e ugelli. </li><li> Inserire la testina di stampa nella stampante. Collegare la testina di stampa con la scheda personalità testa. </li><li> Filtrare l&#39;inchiostro attraverso il filtro dimensione corretta appena prima di caricare nella cartuccia per rimuovere grandi aggregati di particelle che possono ostruire gli ugelli. Iltestina di stampa usata in questo lavoro ha ugelli con un diametro di 40 micron (ad esempio, Konica KM512.); Pertanto inchiostri non devono contenere particelle di diametro superiore a 400 nm. Passare le sospensioni attraverso un 5 micron, seguito da un filtro 1,2 micron fluoruro di polivinilidene (PVDF) per rimuovere eventuali particelle grandi. </li><li> Caricare l&#39;inchiostro nella siringa 150 ml situato sopra la testina di stampa, che fornisce l&#39;inchiostro alla testina di stampa. Attaccare il tappo ermetico in cima alla siringa e attivare la pompa del vuoto. </li><li> Eliminare l&#39;inchiostro attraverso gli ugelli premendo il pulsante &#39;purge&#39; che si trova sulla pompa del vuoto. </li><li> Attraverso il server di stampa sistema di informazione geografica (GIS), i parametri di forma d&#39;onda e la stampa di set-up. Si noti che la stampante possa stampare fino a una velocità di 1,5 metri al secondo, tuttavia per questo inchiostro una velocità di stampa di 0,3 metri al secondo è stato trovato per fornire rivestimento ottimale </li><li> Open GIS software di interfaccia utente e caricare il modello desiderato. </li><li> Print dalla cartuccia caricata secondo il protocollo del produttore. </li><li> Rimuovere il substrato dalla piastra e riscaldare i film stampati a 150 ° C per 30 minuti, seguita da 250 ° C per altri 30 min o su una piastra calda o in un forno. </li></ol> 3. Analisi delle Printed Cinema <ol><li> Utilizzare un microscopio ottico o un microscopio elettronico a scansione (SEM) per guardare la superficie dei film stampati a basso ingrandimento (100X) per analizzare la morfologia superficiale e ad alto ingrandimento (35,000X) analizzare la porosità dei film stampati. Verificare che le immagini mostrano una copertura uniforme, senza crepe e buona porosità. Per informazioni più dettagliate sul funzionamento del SEM si trova nelle seguenti riferimenti 26,27. </li><li> Misurare lo spessore dello strato stampato, utilizzando una tecnica di valutazione appropriato come un profiler superficie secondo il protocollo del produttore. Lo spessore e la porosità dello strato ingegno TiO 2hin DSSCs influenzano la quantità di colorante che può essere assorbita sulla superficie delle nanoparticelle, che influenzano quindi l&#39;efficienza globale di conversione elettrica della cella 18. È quindi un parametro importante per valutare. Utilizzare un profiler superficie (precisione di 1 nm) per misurare lo spessore dei film stampati. </li><li> Misurare la trasmittanza del film, utilizzando una tecnica di valutazione appropriata come lo spettrofotometro UV-visibile (UV-VIS) per determinare la quantità di luce visibile trasmette attraverso la pellicola stampata. Utilizzare il protocollo del produttore. </li></ol> 4. Rendere il cellulare <ol><li> Fare una soluzione colorante mescolando 20 ml di etanolo e 2 mg di colorante di rutenio in un bicchiere di vetro con un agitatore magnetico per 8 ore. </li><li> Immergere il vetro rivestito TiO 2 nella soluzione a temperatura ambiente (da 20 a 25 ° C) per 24 ore per permettere la tintura di assorbire sulla superficie delle particelle di TiO 2. </li><li> Rimuovere il TiO2 </sub&gt; vetro rivestito dalla soluzione e posto su carta velina per assorbire qualsiasi soluzione colorante in eccesso (con il TiO 2 rivolta verso l&#39;alto per evitare la contaminazione). </li><li> Posizionare il pre-taglio 60 micron di spessore distanziatore termoplastico tenuta sulla parte superiore del vetro conduttivo, intorno il rivestimento TiO 2. </li><li> Posizionare il ricoperto platino controelettrodo sopra il pre-taglio 60 micron di spessore distanziatore termoplastico di tenuta in modo che le superfici attive del anodo e il catodo di fronte all&#39;altra. Lasciare sufficiente sovrapposizione tra i due pezzi di vetro in modo che un contatto elettrico può essere realizzato con il vetro conduttivo. Questo dovrebbe avere un pre-foro al centro per consentire il riempimento elettrolita in seguito. </li><li> Calore su una piastra calda ad una temperatura di 110 C e applicare una leggera pressione con una pinzetta sull&#39;area del distanziatore di tenuta. Dopo 30 secondi gli elettrodi devono essere sigillati insieme. </li><li> Colmare il divario tra i due elettrodi con un / elettro tri-ioduro iodurolyte in acetonitrile ad una concentrazione di 50 mM, iniettando attraverso il pre-foro nel vetro rivestito di platino con una siringa. </li></ol>

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S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Influence+of+TiO2+Film+Thickness+on+the+Electrochemical+Behaviour+of+Dye-Sensitized+Solar+Cells.">Influence of TiO2 Film Thickness on the Electrochemical Behaviour of Dye-Sensitized Solar Cells.</a> Int. J. Electrochem. Sci. 6, 3375-3384 (2011).</li><li>Ito, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=High-Efficiency+Organic-Dye-+Sensitized+Solar+Cells+Controlled+by+Nanocrystalline-TiO2+Electrode+Thickness.">High-Efficiency Organic-Dye- Sensitized Solar Cells Controlled by Nanocrystalline-TiO2 Electrode Thickness.</a> Adv. Mater. 18, 1202-1205 (2006).</li><li>Ito, S., Kalyanasundaram, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Dye sensitized solar cells. , 251-266 (2010).</li><li>Tsai, J., Hsu, W., Wu, T., Meen, T., Chong, W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effect+of+compressed+TiO2+nanoparticle+thin+film+thickness+on+the+performance+of+dye-sensitized+solar+cells.">Effect of compressed TiO2 nanoparticle thin film thickness on the performance of dye-sensitized solar cells.</a> Nanoscale Res Lett. 8, 1-6 (2013).</li><li>Shin, I., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Analysis+of+TiO2+thickness+effect+on+characteristic+of+a+dye-sensitized+solar+cell+by+using+electrochemical+impedance+spectroscopy.">Analysis of TiO2 thickness effect on characteristic of a dye-sensitized solar cell by using electrochemical impedance spectroscopy.</a> Curr. Appl. Phys. 10, 422-424 (2010).</li><li>Brus, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Electronic+wave+functions+in+semiconductor+clusters:+experiment+and+theory.">Electronic wave functions in semiconductor clusters: experiment and theory.</a> J. Phys. Chem. 90, 2555-2560 (1986).</li><li>Jung, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=All-Inkjet-Printed,+All-Air-Processed+Solar+Cells.">All-Inkjet-Printed, All-Air-Processed Solar Cells.</a> Adv Energy Mater. 4, 1-9 (2014).</li><li>Cherrington, R., Hughes, D. J., Senthilarasu, S., Goodship, V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Inkjet-Printed+TiO2+Nanoparticles+from+Aqueous+Solutions+for+Dye-Sensitized+Solar+Cells+(DSSCs).">Inkjet-Printed TiO2 Nanoparticles from Aqueous Solutions for Dye-Sensitized Solar Cells (DSSCs).</a> Energy Technology. 3, (2015).</li></ol>

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A particular challenge when formulating inks is the natural tendency for nanoparticles to cluster together. These are known as either aggregates or agglomerates, depending on the nature and strength of the bonds between the particles. The energy of simply stirring particles into water or binder is not great enough to overcome the particle attractive forces preventing the breakup of agglomerates. Ball milling, high shear mixing or ultrasonication are commonly used to break up agglomerated nanoparticles. Various anionic, nonionic, and cationic surfactants and polymers can also be used to provide long-term stabilization. By minimizing the number of these agglomerates, a good quality suspension can be achieved. The fluids should be filtered through the correct size filter just before loading into the cartridge to remove large particle aggregates which can clog the nozzles.
The particle size within the TiO2 layer also has been shown to influence the overall efficiency of DSSCs. The photocatalytic activity of titanium dioxide increases as particle sizes decrease due to an increase in the specific surface area40. A study comparing the efficiency of DSSCs incorporating TiO2 nanoparticles with 5 different sizes ranging from 400 nm to 14 nm and found that those with smaller particle sizes resulted in better electrical conversion efficiencies33.
Inkjet printing is a non-contact deposition technique capable of multi-pass printing. This presents the unique opportunity to rapidly fabricate multilayer devices in one operation on a wide range of substrates with minimal material waste. It also potentially provides a way to integrate other components (such as batteries) into the system through the printing of functional materials41. Although the representative results shown for the inkjet printed devices do not perform as well as the doctor-bladed devices, it demonstrates the potential for the deposition technique. With further ink optimization, it could perform on a comparable level to currently used methods and may provide further scope for cost-effective, environmentally friendly integration of photovoltaic cells onto a wide range of substrates. We hope to improve the efficiency of the inkjet printed devices by increasing the thickness of the printed layer closer to that of the doctor-bladed TiO2 and will continue to look at the printing of other materials and layers within DSSCs.

Conventional silicon solar cells are made from highly pure materials that require expensive and high-energy consuming specialist equipment. These conventional silicon cells incorporate a p-n junction that requires highly pure materials at the interface to generate electron-hole pairs. Dye-sensitized solar cells (DSSCs) have a fundamentally different working principle, where charge generation takes place at the materials interface. This means that processing under vacuum, ultrahigh temperatures or the use of clean room facilities are not required1. Therefore they are seen as a potentially low cost alternative; however up-scaling from small laboratory test cells into large prototypes for industrial manufacturing involves overcoming several issues including the rapid patterning of substrates.
Electronics manufacturing generally requires a degree of patterning, which is either achieved by masking or selective removal of the material after deposition. These steps can be removed through the use of "additive" digital printing techniques such as inkjet printing or spray coating. Digital printing is a promising method for direct deposition of functional materials for electronic devices. The technique can be described as printing from a digital-based pattern directly to a variety of substrates2. They are non-contact methods, which will not damage or contaminate the substrate surface and deposit material only where it is required, resulting in little or no wastage3. These techniques have been highlighted as being ideally suited to being scaled up to high-volume production3. Since digital printing methods use liquid forms of materials dispersed in a solvent, it is critical to understand the deposition of ink to determine the applications of the technique. 
DSSCs have three main components: a porous layer of wide bandgap metal oxide material, a dye that covers the particles, and a "charge transporter" that infiltrates the pores within the porous layer of semiconductor. These are sandwiched in between a transparent conductive electrode and a counter electrode4. The counter electrode is coated with a catalytic material for electron transfer, which in most cases is platinum. Under illumination, the dye molecules will absorb energy in the form of photons. The dye molecules then become excited and charge separation occurs at the interface of the titanium dioxide and the dye. Electrons are ejected into the adjacent metal oxide particles and 'holes' are left behind on the dye molecule. The injected electrons travel through the metal oxide particles and reach the transparent conductive electrode. When a load is connected, the electrons move to the counter electrode through the external circuit and are finally reunited with their counter charges through the redox couple present in the electrolyte1. The nano-structured metal oxide layer within DSSCs plays a critical role in the overall performance of the cell, with material choice, processing methods and nature of the structure all having influencing factors5-10. One of the most important requirements for the photoanode is that it needs to have an extremely large surface area. This is achieved through the deposition of nanoparticle materials, commonly TiO21,11. This has been fabricated by countless different processes, however wet coating techniques such as screen-printing and doctor-blading, are still the most popular approach9,12,13. 
Inkjet technology is a potential manufacturing route for dye-sensitized solar cells. It uses the movement of a piezoelectric crystal to expel a fixed quantity of liquid through a nozzle onto the desired substrate. This deposition method allows material to be jetted very accurately but also at high frequency with a potentially high print speed or deposition rate. Inkjet technology is sensitive to the viscosity of the ink used and this was previously a barrier to the development of functional inks. Recent work in the development of solvents suitable for ink formulation has helped to alleviate this problem, and printing of electronic components using 2D layered materials such as graphene has been demonstrated14. The viscosity of nanoparticle suspensions such as these has been found to depend on the nanoparticle size and concentration15. High concentrations of nanoparticles result in higher viscosities, therefore particle loadings are usually around 10 wt% to avoid nozzle blockages16, however higher concentrations have been achieved17.
The key advantages of inkjet technology include it being non-contact, additive patterning and maskless18. The latter two attributes are due to the ability to position many nozzles together on one or more printheads, with each nozzle separately addressable by the control software. This allows highly complex, multi-layered patterns to be created very rapidly as the printheads move across the substrate. No masking between materials or layers is required as the position of each ink drop is accurately controlled, in some systems to an accuracy of ~1.5 &#181;m19. One of the key benefits is that inkjet technology is mature, with significant development carried out in the latter half of the twentieth century. The result is that the inkjet is a very scalable technology, with roll-to-roll systems capable of printing accurately onto flexible substrates at rates of many meters per second. Traditionally this was used for high volume production, e.g., newspapers. However, developments in technology have allowed the inkjet to be used in roll-to-roll production of electronic circuits using nanoparticulate silver inks20. The inkjet is therefore an attractive process for the potential production of dye-sensitized solar cells by digital printing.

<table><tbody><tr><td>Titanium dioxide</td><td>Sigma Aldrich</td><td>718467</td><td></td></tr><tr><td>Deionized water&amp;nbsp;</td><td></td><td></td><td>Supplied from a filter in the laboratory</td></tr><tr><td>Hydrochloric acid, 2 M (2 N)&amp;nbsp;</td><td>Fisher Scientific</td><td>J/4250/17</td><td></td></tr><tr><td>Dimethylformamide (DMF)</td><td>Fisher Scientific</td><td>D/3840/08</td><td></td></tr><tr><td>Ethanol</td><td>VWR Chemicals</td><td>20721.33</td><td></td></tr><tr><td>Dispersing additive&amp;nbsp;</td><td>Air Products</td><td></td><td></td></tr><tr><td>Defoaming agent</td><td>Air Products</td><td></td><td></td></tr><tr><td>Ethylene glycol</td><td>Fluka</td><td>107-21-1</td><td></td></tr><tr><td>Polyvinylidene fluoride (PVDF) syringe filter</td><td>VWR International</td><td></td><td></td></tr><tr><td>Cleaning detergent&amp;nbsp;</td><td>Fisher Scientific</td><td>10335650</td><td></td></tr><tr><td>Fluorine doped tin oxide (FTO) glass, 8 &amp;Omega;/sq</td><td>Pilkington</td><td></td><td></td></tr><tr><td>Ruthenizer dye</td><td>Solaronix</td><td>21613</td><td></td></tr><tr><td>Pre-cut 60 &amp;micro;m thick thermoplastic sealing film&amp;nbsp;</td><td>Solaronix</td><td>74301</td><td></td></tr><tr><td>50 mM Iodide/tri-iodide electrolyte&amp;nbsp; in acetonitrile</td><td>Solaronix</td><td>31111</td><td></td></tr><tr><td>Platinum coated FTO glass&amp;nbsp;</td><td>Solaronix</td><td>74201</td><td></td></tr><tr><td>Vac&#039;n&#039;Fill Syringe</td><td>Solaronix</td><td>65209</td><td></td></tr><tr><td>Polyimide tape (6.35 mm)</td><td>Onecall Farnell</td><td>1676087</td><td></td></tr></tbody></table>

digital printing of titanium dioxide for dye sensitized solar cells

Silicon solar cell manufacturing is an expensive and high energy consuming process. In contrast, dye sensitized solar cell production is less environmentally damaging with lower processing temperatures presenting a viable and low cost alternative to conventional production. This paper further enhances these environmental credentials by evaluating the digital printing and therefore additive production route for these cells. This is achieved here by investigating the formation and performance of a metal oxide photoelectrode using nanoparticle sized titanium dioxide. An ink-jettable material was formulated, characterized and printed with a piezoelectric inkjet head to produce a 2.6 &#181;m thick layer. The resultant printed layer was fabricated into a functioning cell with an active area of 0.25 cm2 and a power conversion efficiency of 3.5%. The binder-free formulation resulted in a reduced processing temperature of 250 &#176;C, compatible with flexible polyamide substrates which are stable up to temperatures of 350 &#730;C. The authors are continuing to develop this process route by investigating inkjet printing of other layers within dye sensitized solar cells.

Un inchiostro TiO 2 è stato formulato secondo la procedura descritta. La dimensione delle particelle sospese all&#39;interno l&#39;inchiostro è stata misurata usando dispersione dinamica della luce (DLS) e una granulometria media di 80 nanometri (nm) è stata osservata. La viscosità dell&#39;inchiostro in questo lavoro è risultata 3 cP, misurata usando un viscosimetro rotazionale con un adattatore del campione e un diametro albero 18 mm. La tensione superficiale è stata misurata utilizzando un tensiometro ed è stato calcolato per essere una media di 26 mN / m. L&#39;energia superficiale del vetro FTO è stata calcolata secondo la norma europea EN 828 per determinare la bagnabilità di una superficie solida misurando l&#39;angolo di contatto e superficie di energia libera. Dieci gocce di tre differenti liquidi (acqua, glicole etilenico e diiodometano) sono stati dispensati su una superficie di prova piece aereo. Per ogni goccia, l&#39;angolo di contatto a destra ea sinistra erano measured. Da gli angoli di contatto medi di ogni liquido combinata con la sua tensione superficiale, l&#39;energia libera di superficie della provetta viene calcolato. Il metodo Fowkes calcola l&#39;energia di superficie totale (γ) dalla somma dei contributi di interazioni dispersive (γd) e le interazioni γnon dispersivo (γp). Questo metodo ha comportato una energia libera superficiale di 26,45 mN / m per il vetro rivestito FTO. La stampa è stata effettuata secondo la procedura di cui sopra per produrre 5 mm quadrati. Lo spessore dello strato stampato sul vetro è stata misurata usando un profiler superficie. Lo spessore massimo al centro dello strato stampato è stata misurata a 2,6 micron. La trasmittanza del vetro rivestito è stato misurato usando uno spettrometro UV-VIS. Ad una lunghezza d&#39;onda di 700 nm, una trasmittanza del 60% è stata misurata per il film stampato TiO 2 rispetto al 78% per il vetro FTO. <p class="jove_content" fo:keep-together.within-page = &quot;1&quot;&gt; dispositivi fotovoltaici sono stati prodotti secondo lo schema procedimento sopra e caratterizzati direttamente dopo la fabbricazione per minimizzare l&#39;effetto di degradazione causata da acqua e ossigeno nell&#39;aria. Ci sono cinque parametri elettrici prestazioni utilizzati per caratterizzare e confrontare celle solari 28. I valori della corrente di corto circuito (I sc) e tensione a circuito aperto (V oc) possono essere derivate dalla corrente-tensione (IV) della curva. Questi possono poi essere utilizzati per determinare il fattore di riempimento (FF) e l&#39;efficienza di conversione di potenza (η). Il FF dà un rapporto delle cellule effettiva potenza massima al prodotto della tensione a circuito aperto e corto circuito corrente 29. Questo è un parametro fondamentale per valutare le prestazioni delle celle solari. Un alto FF significa basse perdite elettrochimici, mentre una bassa FF indica che c&#39;è spazio per il miglioramento. Diversi fattori sono noti per influenzare la FF compresa la qualità e l&#39;interfaccia degli strati all&#39;interno della cellula. DSSC incorpora una coppia redox ioduro / triiodide con il record di efficienza del rapporto di 11,9% di riempimento fattori di 0,71 30. Tutti questi parametri devono essere determinati in condizioni di prova standard in cui la temperatura del dispositivo è di 25 ° C, la distribuzione irraggiamento spettrale della luce ha una massa d&#39;aria di 1,5, irradianza totale misurata (E m) presso la cella solare è di 100 mW / cm 2. Massimo teorico per l&#39;efficienza di conversione per una singola cella giunzione pn è stato ampiamente segnalato come 37,7% 31, tuttavia per DSSCs è stato segnalato che l&#39;efficienza massima è più vicino al 15,1% con un inizio assorbimento a 920 nm 32. La corrente di uscita e tensioni sono stati misurati utilizzando un misuratore di sorgente mentre le cellule sono state illuminate con un / cm sorgente luminosa 100 mW 2 con filtro per abbinare la distribuzione irradianza spettrale con una massa d&#39;aria di 1,5. I risultati sono stati confrontati con una cellaprodotta utilizzando un livello medico-pale TiO 2 con una pasta disponibile in commercio, che è una miscela di particelle di anatasio 20 nm e 450 nm. Lo strato stampato ha una superficie di 0,25 cm 2 e uno spessore medio di 18 micron che è stata misurata utilizzando un profiler superficie. Un confronto tra l&#39;efficienza fotoelettrico tra i due dispositivi è illustrata in Figura 1 e Tabella 1. Diversi studi hanno indagato il rapporto tra lo spessore dello strato di TiO 2 e l&#39;efficienza di conversione entro DSSCs. I risultati variano notevolmente, con spessore di pellicola ottimale segnalato da qualsiasi punto tra 9,5 micron e 20 micron 33-39. Tabella 1 delinea gli spessori degli strati TiO 2 incisioni e le efficienze. Lo spessore del getto di inchiostro stampato TiO 2 è significativamente inferiore al medico pale TiO 2, risultantein una minore efficienza. Il lavoro futuro esaminerà l&#39;uso di leganti organici nella formulazione dell&#39;inchiostro per aumentare lo spessore dello strato di inchiostro stampato. <img alt="Figura 1" src="/files/ftp_upload/53963/53963fig1.jpg" /> Figura 1. Curve caratteristiche di DSSCs con getto d&#39;inchiostro stampato e dottore a lame TiO 2 strati. Curve attuale densità / tensione per DSSCs incorporano un getto di inchiostro stampato TiO 2 strati e uno strato medico-lama TiO 2. La densità di corrente di corto circuito nel dispositivo con il getto di inchiostro stampato TiO2 strato è significativamente inferiore rispetto al dispositivo con il medico lama strato di TiO2 con una conseguente minore efficienza generale di conversione. <a href="https://jove.unicartagenaproxy.elogim.com/files/ftp_upload/53963/53963fig1large.jpg" target="_blank">Si prega di cliccare qui per vedere una versione più grande di questa figura.</a> <table><tbody><tr><tdrowspan = &quot;3&quot;&gt; </td><td> Corrente di corto circuito </td><td> tensione a circuito aperto </td><td rowspan="3"> Fattore di riempimento </td><td> Efficienza </td><td> Spessore </td></tr><tr><td> (mA / cm 2) </td><td> (MV) </td><td></td><td></td></tr><tr><td></td><td></td><td> (%) </td><td> (Micron) </td></tr><tr><td> a getto d&#39;inchiostro stampato </td><td> 9.42 </td><td> 760 </td><td> 0.49 </td><td> 3.5 </td><td> 2.6 </td></tr><tr><td> medico lame </td><td> 11 </td><td> 756 </td><td> 0.58 </td><td> 4.8 </td><td> 18 </td></tr></tbody></table> Tabella 1. Key Performance caratteristiche delle cellule in Figura 1. Questa tabella mette a confronto i parametri chiave della cella solare, tra cui la tensione a circuito aperto (V oc), corrente di corto circuito (I SC) che determinano l&#39;efficienza (η) sotto la luce specificato condizioni sono presentati. I parametri ocella fa prodotta utilizzando un livello medico-lama TiO2 sono stati inclusi anche per il confronto. I fattori di riempimento (FF) di entrambi i dispositivi sono molto bassi che viene generalmente attribuito ad una elevata resistenza interna della cella.

Watch this Scientific Journal Video about Digital Printing of Titanium Dioxide for Dye Sensitized Solar Cells at JoVE.com

Digital Printing of Titanium Dioxide for Dye Sensitized Solar Cells

This paper investigates the suitability of inkjet printing for the manufacturing of dye-sensitized solar cells. A binder-free TiO2 nanoparticle ink was formulated and printed onto a FTO glass substrate. The printed layer was fabricated into a cell with an active area of 0.25 cm2 and an efficiency of 3.5%.

La stampa digitale di biossido di titanio per le celle solari dye sensibilizzato

Silicon solar cell manufacturing is an expensive and high energy consuming process. In contrast, dye sensitized solar cell production is less ...

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12.7K Views.  University of Warwick. This paper investigates the suitability of inkjet printing for the manufacturing of dye-sensitized solar cells. A binder-free TiO2 nanoparticle ink was formulated and printed onto a FTO glass substrate. The printed layer was fabricated into a cell with an active area of 0.25 cm2 and an efficiency of 3.5%.

Video: Digital Printing of Titanium Dioxide for Dye Sensitized Solar Cells

Integrating a Triplet-triplet Annihilation Up-conversion System to Enhance Dye-sensitized Solar Cell Response to Sub-bandgap Light

The poor response of dye-sensitized solar cells (DSCs) to red and infrared light is a significant impediment to the realization of higher photocurrents and hence higher efficiencies. Photon up-conversion by way of triplet-triplet annihilation (TTA-UC) is an attractive technique for using these otherwise wasted low energy photons to produce photocurrent, while not interfering with the photoanodic performance in a deleterious manner. Further to this, TTA-UC has a number of features, distinct from other reported photon up-conversion technologies, which renders it particularly suitable for coupling with DSC technology. In this work, a proven high performance TTA-UC system, comprising a palladium porphyrin sensitizer and rubrene emitter, is combined with a high performance DSC (utilizing the organic dye D149) in an integrated device. The device shows an enhanced response to sub-bandgap light over the absorption range of the TTA-UC sub-unit resulting in the highest figure of merit for up-conversion assisted DSC performance to date.

An integrated device, incorporating a dye-sensitized solar cell and triplet-triplet annihilation up-conversion unit was produced, affording enhanced light harvesting, from a wider section of the solar spectrum. Under modest irradiation levels a significantly enhanced response to low energy photons was demonstrated, yielding a record figure of merit for dye-sensitized solar cells.

L&#39;integrazione di un Triplet-tripletta Annihilation sistema Up-conversione per migliorare Dye-sensibilizzati Risposta Solar Cell a Sub-bandgap Luce

The poor response of dye-sensitized solar cells (DSCs) to red and infrared light is a significant impediment to the realization of higher photocurrents ...

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Integration of Light Trapping Silver Nanostructures in Hydrogenated Microcrystalline Silicon Solar Cells by Transfer Printing

One of the potential applications of metal nanostructures is light trapping in solar cells, where unique optical properties of nanosized metals, commonly known as plasmonic effects, play an important role. Research in this field has, however, been impeded owing to the difficulty of fabricating devices containing the desired functional metal nanostructures. In order to provide a viable strategy to this issue, we herein show a transfer printing-based approach that allows the quick and low-cost integration of designed metal nanostructures with a variety of device architectures, including solar cells. Nanopillar poly(dimethylsiloxane) (PDMS) stamps were fabricated from a commercially available nanohole plastic film as a master mold. On this nanopatterned PDMS stamps, Ag films were deposited, which were then transfer-printed onto block copolymer (binding layer)-coated hydrogenated microcrystalline Si (&#181;c-Si:H) surface to afford ordered Ag nanodisk structures. It was confirmed that the resulting Ag nanodisk-incorporated &#181;c-Si:H solar cells show higher performances compared to a cell without the transfer-printed Ag nanodisks, thanks to plasmonic light trapping effect derived from the Ag nanodisks. Because of the simplicity and versatility, further device application would also be feasible thorough this approach.

A viable transfer printing-based methodology to introduce plasmonic metal nanostructures in solar cells is described. Using nanopillar poly(dimethylsiloxane) stamps, an Ag-based ordered nanodisk array was integrated with standard hydrogenated microcrystalline Si solar cells, which led to improved device performances due to plasmonic light trapping.

Integrazione di luce Trapping Argento Nanostrutture in silicio microcristallino idrogenato celle solari tramite bonifico stampa

One of the potential applications of metal nanostructures is light trapping in solar cells, where unique optical properties of nanosized metals, commonly ...

Printing Fabrication of Bulk Heterojunction Solar Cells and In Situ Morphology Characterization

Polymer-based materials hold promise as low-cost, flexible efficient photovoltaic devices. Most laboratory efforts to achieve high performance devices have used devices prepared by spin coating, a process that is not amenable to large-scale fabrication. This mismatch in device fabrication makes it difficult to translate quantitative results obtained in the laboratory to the commercial level, making optimization difficult. Using a mini-slot die coater, this mismatch can be resolved by translating the commercial process to the laboratory and characterizing the structure formation in the active layer of the device in real time and in situ as films are coated onto a substrate. The evolution of the morphology was characterized under different conditions, allowing us to propose a mechanism by which the structures form and grow. This mini-slot die coater offers a simple, convenient, material efficient route by which the morphology in the active layer can be optimized under industrially relevant conditions. The goal of this protocol is to show experimental details of how a solar cell device is fabricated using a mini-slot die coater and technical details of running in situ structure characterization using the mini-slot die coater.

Printing Fabrication of Bulk Heterojunction Solar Cells and In Situ Morphology Characterization

Here, we present a protocol to fabricate organic thin film solar cells using a mini-slot die coater and related in-line structure characterizations using synchrotron scattering techniques.

La stampa Fabbricazione di massa eterogiunzione celle solari e<em&gt; In Situ</em&gt; Morfologia Caratterizzazione

Polymer-based materials hold promise as low-cost, flexible efficient photovoltaic devices. Most laboratory efforts to achieve high performance devices ...

Fabrication of Fully Solution Processed Inorganic Nanocrystal Photovoltaic Devices

We demonstrate a method for the preparation of fully solution processed inorganic solar cells from a spin and spray coating deposition of nanocrystal inks. For the photoactive absorber layer, colloidal CdTe and CdSe nanocrystals (3-5 nm) are synthesized using an inert hot injection technique and cleaned with precipitations to remove excess starting reagents. Similarly, gold nanocrystals (3-5 nm) are synthesized under ambient conditions and dissolved in organic solvents. In addition, precursor solutions for transparent conductive indium tin oxide (ITO) films are prepared from solutions of indium and tin salts paired with a reactive oxidizer. Layer-by-layer, these solutions are deposited onto a glass substrate following annealing (200-400 &#176;C) to build the nanocrystal solar cell (glass/ITO/CdSe/CdTe/Au). Pre-annealing ligand exchange is required for CdSe and CdTe nanocrystals where films are dipped in NH4Cl:methanol to replace long-chain native ligands with small inorganic Cl- anions. NH4Cl(s) was found to act as a catalyst for the sintering reaction (as a non-toxic alternative to the conventional CdCl2(s) treatment) leading to grain growth (136&#177;39 nm) during heating. The thickness and roughness of the prepared films are characterized with SEM and optical profilometry. FTIR is used to determine the degree of ligand exchange prior to sintering, and XRD is used to verify the crystallinity and phase of each material. UV/Vis spectra show high visible light transmission through the ITO layer and a red shift in the absorbance of the cadmium chalcogenide nanocrystals after thermal annealing. Current-voltage curves of completed devices are measured under simulated one sun illumination. Small differences in deposition techniques and reagents employed during ligand exchange have been shown to have a profound influence on the device properties. Here, we examine the effects of chemical (sintering and ligand exchange agents) and physical treatments (solution concentration, spray-pressure, annealing time and annealing temperature) on photovoltaic device performance.

This protocol describes the synthesis and solution deposition of inorganic nanocrystals layer by layer to produce thin film electronics on non-conductive surfaces. Solvent-stabilized inks can produce complete photovoltaic devices on glass substrates via spin and spray coating following post-deposition ligand exchange and sintering.

Fabbricazione di inorganici nanocristalli fotovoltaici dispositivi completamente Soluzione Processing

We demonstrate a method for the preparation of fully solution processed inorganic solar cells from a spin and spray coating deposition of nanocrystal ...

Morphology Control for Fully Printable Organic&#8211;Inorganic Bulk-heterojunction Solar Cells Based on a Ti-alkoxide and Semiconducting Polymer

The photoactive layer of a typical organic thin-film bulk-heterojunction (BHJ) solar cell commonly uses fullerene derivatives as the electron-accepting material. However, fullerene derivatives are air-sensitive; therefore, air-stable material is needed as an alternative. In the present study, we propose and describe the properties of Ti-alkoxide as an alternative electron-accepting material to fullerene derivatives to create highly air-stable BHJ solar cells. It is well-known that controlling the morphology in the photoactive layer, which is constructed with fullerene derivatives as the electron acceptor, is important for obtaining a high overall efficiency through the solvent method. The conventional solvent method is useful for high-solubility materials, such as fullerene derivatives. However, for Ti-alkoxides, the conventional solvent method is insufficient, because they only dissolve in specific solvents. Here, we demonstrate a new approach to morphology control that uses the molecular bulkiness of Ti-alkoxides without the conventional solvent method. That is, this method is one approach to obtain highly efficient, air-stable, organic-inorganic bulk-heterojunction solar cells.

A method for fully printable, fullerene-free, highly air-stable, bulk-heterojunction solar cells based on Ti alkoxides as the electron acceptor and the electron-donating polymer fabrication is described here. Moreover, a method for controlling the morphology of the photoactive layer through the molecular bulkiness of the Ti-alkoxide units is reported.

Controllo Morfologia per Bulk-eterogiunzione completamente stampabili celle solari organiche-inorganici a base di un Ti-alcossido e semiconduttore Polymer

The photoactive layer of a typical organic thin-film bulk-heterojunction (BHJ) solar cell commonly uses fullerene derivatives as the electron-accepting ...

Electrospinning of Photocatalytic Electrodes for Dye-sensitized Solar Cells

This work demonstrates a protocol to fabricate a fiber-based photoanode for dye-sensitized solar cells, consisting of a light-scattering layer made of electrospun titanium dioxide nanofibers (TiO2-NFs) on top of a blocking layer made of commercially available titanium dioxide nanoparticles (TiO2-NPs). This is achieved by first electrospinning a solution of titanium (IV) butoxide, polyvinylpyrrolidone (PVP), and glacial acetic acid in ethanol to obtain composite PVP/TiO2 nanofibers. These are then calcined at 500 &#176;C to remove the PVP and to obtain pure anatase-phase titania nanofibers. This material is characterized using scanning electron microscopy (SEM) and powder X-ray diffraction (XRD). The photoanode is prepared by first creating a blocking layer through the deposition of a TiO2-NPs/terpineol slurry on a fluorine-doped tin oxide (FTO) glass slide using doctor blading techniques. A subsequent thermal treatment is performed at 500 &#176;C. Then, the light-scattering layer is formed by depositing a TiO2-NFs/terpineol slurry on the same slide, using the same technique, and calcinating again at 500 &#176;C. The performance of the photoanode is tested by fabricating a dye-sensitized solar cell and measuring its efficiency through J-V curves under a range of incident light densities, from 0.25-1 Sun.

The overall goal of this project was to use electrospinning to fabricate a photoanode with improved performance for dye-sensitized solar cells.

Elettrospinning degli elettrodi fotocatalitici per le celle solari sensibilizzate a tinte

This work demonstrates a protocol to fabricate a fiber-based photoanode for dye-sensitized solar cells, consisting of a light-scattering layer made of ...

Inkjet Printing All Inorganic Halide Perovskite Inks for Photovoltaic Applications

A method for synthesizing photoactive inorganic&#160;perovskite quantum dot inks and an inkjet printer deposition method, using the synthesized inks, are demonstrated. The ink synthesis is based on a simple wet chemical reaction and the inkjet printing protocol is a facile step by step method. The inkjet printed thin films have been characterized by X-ray diffraction, optical absorption spectroscopy, photoluminescent spectroscopy, and electronic transport measurements. X-ray diffraction of the printed quantum dot films indicates a crystal structure consistent with an orthorhombic room temperature phase with (001) orientation. In conjunction with other characterization methods, the X-ray diffraction&#160;measurements show high quality films can be obtained through the inkjet printing method.

A protocol for synthesizing inorganic-lead-halide hybrid perovskite quantum dot inks for inkjet printing and the protocol for preparing and printing the quantum dot inks in an inkjet printer with post characterization techniques are presented.

A getto d'inchiostro stampa tutti gli inchiostri di Perovskite alogenuro inorganici per applicazioni fotovoltaiche

A method for synthesizing photoactive inorganic&#160;perovskite quantum dot inks and an inkjet printer deposition method, using the synthesized inks, are ...

Chimica

Photopatterning Proteins and Cells in Aqueous Environment Using TiO2 Photocatalysis

Organic contaminants adsorbed on the surface of titanium dioxide (TiO2) can be decomposed by photocatalysis under ultraviolet (UV) light. Here we describe a novel protocol employing the TiO2 photocatalysis to locally alter cell affinity of the substrate surface. For this experiment, a thin TiO2 film was sputter-coated on a glass coverslip, and the TiO2 surface was subsequently modified with an organosilane monolayer derived from octadecyltrichlorosilane (OTS), which inhibits cell adhesion. The sample was immersed in a cell culture medium, and focused UV light was irradiated to an octagonal region. When a neuronal cell line PC12 cells were plated on the sample, cells adhered only on the UV-irradiated area. We further show that this surface modification can also be performed in situ, i.e., even when cells are growing on the substrate. Proper modification of the surface required an extracellular matrix protein collagen to be present in the medium at the time of UV irradiation. The technique presented here can potentially be employed in patterning multiple cell types for constructing coculture systems or to arbitrarily manipulate cells under culture.

Photopatterning Proteins and Cells in Aqueous Environment Using TiO2 Photocatalysis

We describe a protocol for modifying cell affinity of a scaffold surface in aqueous environment. The method takes advantage of titanium dioxide photocatalysis to decompose organic film in the photo-irradiated region. We show that it can be used to create microdomains of scaffolding proteins, both ex situ and in situ.

Photopatterning proteine ​​e cellule in acquosa ambiente utilizzando TiO<sub&gt; 2</sub&gt; Fotocatalisi

Organic contaminants adsorbed on the surface of titanium dioxide (TiO2) can be decomposed by photocatalysis under ultraviolet (UV) light. Here we describe ...

Bioingegneria

Vibrational Spectra of a N719-Chromophore/Titania Interface from Empirical-Potential Molecular-Dynamics Simulation, Solvated by a Room Temperature Ionic Liquid

The accurate molecular simulation prediction of vibrational spectra, and other structural, energetic and spectral characteristics, of photo-active metal-oxide surfaces in contact with light-absorbing dyes is an ongoing thorny and elusive challenge in physical chemistry. With this in mind, a molecular-dynamics (MD) simulation were performed by using optimized empirical potentials for a well-representative and prototypical dye-sensitized solar cell (DSC) solvated by a widely-studied room temperature ionic liquid (RTIL), in the guise of a [bmim]+[NTf2]- RTIL solvating an N719-sensitizing dye adsorbed onto 101 anatase-titania. In doing so, important insights were gleaned into how using a RTIL as the electrolytic hole acceptor modulates the dynamical and vibrational properties of a N719 dye, estimating the spectra for the DSC photo-active interface via Fourier transformation of mass-weighted velocity autocorrelation functions from MD. The acquired vibrational spectra were compared with the experiment spectra and those sampled from ab initio molecular dynamics (AIMD); in particular, various empirical-potential spectra generated from MD provide insight into how partial-charge charge parameterization of the ionic liquid affects vibrational spectra prediction. In any event, careful fitting of empirical force-field models has been shown to be an effective tool in handling DSC vibrational properties, when validated by AIMD and an experiment.

A dye-sensitized solar cell was solvated by RTILs; using optimized empirical potentials, a molecular dynamics simulation was applied to compute vibrational properties. The obtained vibrational spectra were compared with experiment and ab initio molecular dynamics; various empirical potential spectra show how partial-charge charge parameterization of the ionic liquid affects vibrational spectra prediction.

Spettri vibrazionali di un'interfaccia N719-Chromophore/Titania da Simulazione empirica-potenziale di dinamica molecolare, solvata da un liquido ionico a temperatura ambiente

The accurate molecular simulation prediction of vibrational spectra, and other structural, energetic and spectral characteristics, of photo-active ...

Fully Automated Centrifugal Microfluidic Device for Ultrasensitive Protein Detection from Whole Blood

Enzyme-linked immunosorbent assay (ELISA) is a promising method to detect small amount of proteins in biological samples. The devices providing a platform for reduced sample volume and assay time as well as full automation are required for potential use in point-of-care-diagnostics. Recently, we have demonstrated ultrasensitive detection of serum proteins, C-reactive protein (CRP) and cardiac troponin I (cTnI), utilizing a lab-on-a-disc composed of TiO2 nanofibrous (NF) mats. It showed a large dynamic range with femto molar (fM) detection sensitivity, from a small volume of whole blood in 30 min. The device consists of several components for blood separation, metering, mixing, and washing that are automated for improved sensitivity from low sample volumes. Here, in the video demonstration, we show the experimental protocols and know-how for the fabrication of NFs as well as the disc, their integration and the operation in the following order: processes for preparing TiO2 NF mat; transfer-printing of TiO2 NF mat onto the disc; surface modification for immune-reactions, disc assembly and operation; on-disc detection and representative results for immunoassay. Use of this device enables multiplexed analysis with minimal consumption of samples and reagents. Given the advantages, the device should find use in a wide variety of applications, and prove beneficial in facilitating the analysis of low abundant proteins.

This protocol demonstrates how to achieve femto molar detection sensitivity of proteins in 10 &#181;L of whole blood within 30 min. This can be achieved by using electrospun nanofibrous mats integrated in a lab-on-a-disc, which offers high surface area as well as effective mixing and washing for enhanced signal-to-noise ratio.

Completamente dispositivo automatizzato centrifuga Microfluidic per il rilevamento di proteine ​​Ultrasensitive da sangue intero

Enzyme-linked immunosorbent assay (ELISA) is a promising method to detect small amount of proteins in biological samples. The devices providing a platform ...

La stampa digitale di biossido di titanio per le celle solari dye sensibilizzato

Riepilogo

Esplora Altri Video

Capitoli in questo video

L'integrazione di un Triplet-tripletta Annihilation sistema Up-conversione per migliorare Dye-sensibilizzati Risposta Solar Cell a Sub-bandgap Luce

Integrazione di luce Trapping Argento Nanostrutture in silicio microcristallino idrogenato celle solari tramite bonifico stampa

La stampa Fabbricazione di massa eterogiunzione celle solari e

Fabbricazione di inorganici nanocristalli fotovoltaici dispositivi completamente Soluzione Processing

Controllo Morfologia per Bulk-eterogiunzione completamente stampabili celle solari organiche-inorganici a base di un Ti-alcossido e semiconduttore Polymer

Elettrospinning degli elettrodi fotocatalitici per le celle solari sensibilizzate a tinte

A getto d'inchiostro stampa tutti gli inchiostri di Perovskite alogenuro inorganici per applicazioni fotovoltaiche

Photopatterning proteine e cellule in acquosa ambiente utilizzando TiO

Spettri vibrazionali di un'interfaccia N719-Chromophore/Titania da Simulazione empirica-potenziale di dinamica molecolare, solvata da un liquido ionico a temperatura ambiente

Completamente dispositivo automatizzato centrifuga Microfluidic per il rilevamento di proteine Ultrasensitive da sangue intero

La stampa digitale di biossido di titanio per le celle solari dye sensibilizzato

Riepilogo

Esplora Altri Video

Capitoli in questo video

L'integrazione di un Triplet-tripletta Annihilation sistema Up-conversione per migliorare Dye-sensibilizzati Risposta Solar Cell a Sub-bandgap Luce

Integrazione di luce Trapping Argento Nanostrutture in silicio microcristallino idrogenato celle solari tramite bonifico stampa

La stampa Fabbricazione di massa eterogiunzione celle solari e

Fabbricazione di inorganici nanocristalli fotovoltaici dispositivi completamente Soluzione Processing

Controllo Morfologia per Bulk-eterogiunzione completamente stampabili celle solari organiche-inorganici a base di un Ti-alcossido e semiconduttore Polymer

Elettrospinning degli elettrodi fotocatalitici per le celle solari sensibilizzate a tinte

A getto d'inchiostro stampa tutti gli inchiostri di Perovskite alogenuro inorganici per applicazioni fotovoltaiche

Photopatterning proteine ​​e cellule in acquosa ambiente utilizzando TiO

Spettri vibrazionali di un'interfaccia N719-Chromophore/Titania da Simulazione empirica-potenziale di dinamica molecolare, solvata da un liquido ionico a temperatura ambiente

Completamente dispositivo automatizzato centrifuga Microfluidic per il rilevamento di proteine ​​Ultrasensitive da sangue intero

Photopatterning proteine e cellule in acquosa ambiente utilizzando TiO

Completamente dispositivo automatizzato centrifuga Microfluidic per il rilevamento di proteine Ultrasensitive da sangue intero