这项工作得到了科技部台湾中华民国国家科技计划赞助NSC 103-2112-M-002-008-MY3的支持。

1.制造Microchip <ol><li> 制备ITO电极 <ol><li>使用商业插图软件绘制交叉图案。将对角电极之间的距离设置为160μm，并使十字图案的臂宽30 mm，长55 mm， 如图1所示。将插图文件保存为DXF文件。 </li><li>使用玻璃切割机将ITO玻璃修剪成尺寸为25 mm x 50 mm（宽x长）。使用75％乙醇和去离子水冲洗ITO玻璃几次。 </li><li>将ITO玻璃放在脉冲光纤激光打标机上。通过将ITO玻璃和激光之间的距离调整到279.5mm，将激光对焦在ITO玻璃的表面上。 注意:此处使用的激光器具有以下规格:1,064 nm，20 W，90至120 ns脉冲宽度和20至80 kHz脉冲重复频率，脉冲光强度约为5 x 10 5 W / cm 2）。 </li><li>直接将图示文件（DXF文件）输入激光打标机的计算机上。单击"标记参数"按钮，输入以下参数:速度"800 mm / s"权力"60％"和频率"40 kHz"。勾选"框架"，"填充"和"填充第一"条款。 <ol><li>点击"预览"按钮将图案放置在ITO玻璃中心。点击"标记样品"按钮对ITO玻璃进行图案化（ 图 1A ）。 </li></ol></li></ol></li><li> 设置四相发电机并连接实验微芯片 <ol><li>构建逆变器的电路，如图2A所示。 </li><li>通过与胶带直接接触将4根电线连接在四相电极上，如图2C所示。划分"通"el 1"的功能发生器分为两个分支，使用双BNC连接器。 <ol><li>将一个分支连接到连接到ITO电极的电线（＃1），另一个连接到逆变器的输入端。将反相器的输出连接到导线（＃3）， 如图2 B所示。 </li></ol></li><li>以与步骤1.2.2相同的步骤连接"通道2"，但如图2B所示连接到电线（＃2和＃4）。 </li><li>对于EROT实验，将两个通道之间的相移设置为90°，直接在函数发生器上。在实验过程中，以0.5-4 V pp电压振幅和频率范围为100 Hz至5 MHz施加正弦波， 如图2 D所示。 </li><li>对于DEP实验，将通道1的一个分支连接到连接到ITO电极的另一个线（＃1）输入反相器。将变频器的输出连接到电线（＃2）。使用相同的步骤连接通道2，但连接到电线（＃3和＃4）。 </li><li>在0°之间直接在函数发生器上设置2个通道之间的相移。在实验过程中，以0.5-4 V pp电压振幅和频率范围为100 Hz至5 MHz施加正弦波， 如图2 D所示。 </li></ol></li></ol> 2.准备样品<ol><li> Janus颗粒的制备 <ol><li>以2,200×g离心2μm二氧化硅颗粒水悬浮液（10％w / w）1分钟。 </li><li>将2μL沉淀二氧化硅颗粒吸入1.5 mL微量离心管中，加入500μL乙醇（99.5％v / v）。 注意:上清液不需要丢弃;只需将其保存在4°C的冰箱中即可。在pipettin之前不需要重新悬浮G。 </li><li>使用超声波仪（43kHz，50W）超声处理乙醇 - 二氧化硅颗粒悬浮液1分钟，然后以2200×g离心3分钟。 </li><li>用500μL乙醇代替上清液，重复步骤2.1.3三次。 </li><li>用8μL乙醇代替上清液，并使用超声波仪（43 kHz，50 W）超声处理乙醇 - 二氧化硅颗粒悬浮液3 min。 注意:在此步骤中约10μL乙醇 - 二氧化硅颗粒悬浮液应保留在管中。 </li><li>移取2μL乙醇 - 二氧化硅颗粒悬浮液，并将其放在普通玻璃载玻片（宽度:25mm，长度:75mm，厚度:1.2mm）上以形成液滴。 注意:这一数量的颗粒悬浮液足以制备5-6片幻灯片的单层（每张幻灯片2μL）。 </li><li>用玻璃杯缓慢地将乙醇 - 二氧化硅颗粒微滴略微地拉成二氧化硅颗粒单层（ 图3） </st荣&gt; A ）。 </li><li>将具有二氧化硅颗粒的单层的载玻片放入用Au涂覆的溅射装置中。 <ol><li>从100 mTorr的溅射室中取出空气，并注入氩气10分钟（用氩气代替空气）。停止注入氩气，然后从70 mTorr的室中取出氩气。 </li><li>将电流设置为15 mA，持续200 s。 （ 图 3B ）;在此步骤中已经准备了Janus颗粒。 </li></ol></li><li>在溅射的载玻片上滴入20μL去离子水，并使用正常的200μL移液管尖从单层刮掉Janus颗粒。 注意:在此步骤中，从单层刮掉的Janus颗粒悬浮在DI水滴中。 </li><li>移取Janus颗粒悬液液滴并滴入另一个1.5 mL离心管中。 </li><li>使用Janus颗粒悬浮液通过用DI水稀释至合适的浓度来制备样品为实验。 注意:本文所述实验中颗粒悬浮液的浓度约为2,000次/μL。 </li></ol></li><li> 完全涂覆金属颗粒的制备 14 <ol><li>以10:1的重量比混合PDMS聚合物基质和固化剂。 </li><li>围绕玻璃片粘贴以形成容器的侧壁。将PDMS的混合物倒入带胶片上以获得2-3mm的PDMS层， 如图4A所示。 </li><li>将胶带滑块（容器）与PDMS混合物放入气密室中，运行真空泵30分钟以除去PDMS混合物中的气泡。 </li><li>将带有PDMS混合物的胶带（容器）（步骤2.2.3）放入烤箱。在70℃下固化PDMS混合物2小时以形成PDMS印章。 </li><li> PDMS邮票固化后，取出幻灯片和胶带，以获取PDMS邮票，表面其最初附着在玻璃板上，形成平坦的表面，如图4B所示。 </li><li>按照2.1.1-2.1.8中的步骤在幻灯片上制备单层Janus粒子。 </li><li>使用PDMS邮票的平整表面均匀压印单层。 </li><li>将PDMS邮票与从步骤2.1.8中制作的载玻片倒置的Janus粒子单层进入待镀Au的溅射装置中。 <ol><li>从100 mTorr的溅射室中取出空气，并注入氩气10分钟（用氩气代替空气）。停止注入氩气，然后从70 mTorr的室中取出氩气。 </li><li>将电流设置为15 mA，持续200 s（ 图4 C ）;在该步骤中已经制备了完全涂覆的金属颗粒。 </li></ol></li><li>按照2.1.9-2.1.11中的步骤准备实验样品。 </li> &lt;/醇&gt; </li></ol>交流电动测量实验<ol><li> 包裹5片石蜡膜以制备间隔物。使用热枪将ITO电极阵列与厚度为500μm的膜间隔物结合，并将电极放置在显微镜载物台上。 <ol><li>将8μL在步骤2.1和2.2中制备的颗粒悬浮液滴到交叉电极阵列的中心。在隔片上放置一个盖玻片。 </li></ol></li><li> 对于EROT实验，在功能发生器上，将2个通道之间的相移设置为90°。在实验期间以0.5-4 V pp电压幅度和范围从100 Hz到5 MHz的频率施加正弦波（基于步骤1.2.2-1.2.3中的连接）。 <ol><li>通过单击函数发生器上的"波形"按钮选择波形。使用功能ge上的编号按钮输入电压和频率值然后点击"输出"按钮打开交流信号。 </li></ol></li><li>对于DEP实验，将2个通道之间的相移设置为0°。在实验期间（基于步骤1.2.5中的连接），以0.5-4 V pp电压幅度和频率100 Hz至5 MHz施加正弦波，方法如第3.2.1节中那样设置函数发生器。 </li><li>通过点击"输出"按钮打开交流信号，并使用相机用40X，NA 0.6物镜在倒置光学显微镜下捕获颗粒运动和旋转的图像。 </li><li>将粒子运动和旋转的图像输入到软件中，并通过粒子跟踪分析粒子的轨迹，以获得粒子和角速度。 注意:"Image J"软件及其"MultiTracker"插件用于图像二值化和粒子跟踪。 </li></ol>

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作者没有什么可以披露的。

使用光纤激光打标机制造ITO电极阵列提供了制备具有任意图案的电极的快速方法。然而，与通过传统方法制造的金属电极相比，该方法仍然存在诸如较少的电荷载体和较低的ITO电极的制造精度的缺点。这些缺点可能会限制一些实验。例如，当电极之间存在大的距离时，较少的载流子可能影响电场的分布。此外，图案化参数的调整是该方法中的关键步骤，其直接影响ITO电极阵列的质量。例如，激光?...

以罗马神命名为双面的Janus粒子是不对称的粒子，其双面在物理或化学上具有不同的表面性质1,2 。由于这种不对称特征，Janus颗粒在电场下表现出特殊的反应，例如DEP3,4,5,6，EROT2和诱导电荷电泳（ICEP） 7,8,9 。最近报道了几种制备Janus颗粒的方法，包括Pickering乳液法10 ，电动液体共喷射法11和微流体光聚合法12 。然而，这些方法需要一系列的组合提示设备和程序。本文介绍了一种简单的方法来制备Janus颗粒和完全涂覆的金属颗粒。在干燥过程中制备单层微尺度二氧化硅颗粒，并将其放入用Au涂覆的溅射装置中。颗粒的一个半球是阴影的，只有另一个半球涂有Au 2，13。 Janus颗粒的单层用聚二甲基硅氧烷（PDMS）印模冲压，然后用第二次涂覆工艺处理以制备完全涂覆的金属颗粒14 。 为了表征Janus颗粒的电学性质，不同的AC电动反应（如DEP，EROT和电取向）被广泛使用9,15,16,17,18 <s， 19 。例如，EROT是在外部施加的旋转电场2,9,15,16处的颗粒的稳态旋转响应。通过测量EROT，可以获得颗粒的感应偶极子与电场之间的相互作用。由诱发偶极子和不均匀电场之间的相互作用产生的DEP能够导致粒子运动3,4,5,9,15 。可以将不同种类的颗粒吸引到（正DEP）或排斥（负DEP）电极边缘，其用作操纵和表征微流体装置中的颗粒的一般方法。翻译（DEP）和旋转<html>电场下的粒子特征（EROT）分别由克劳修斯 - 莫索蒂（CM）因子的实部和虚部支配。 CM因子取决于粒子和周围液体的电学性质，从特征频率ωC =2σ/ aC DL ，DEP和EROT可知，其中σ是液体电导率，a是粒子半径， C DL是电双层15,16的电容。为了测量颗粒的EROT和DEP，需要特别设计的电极阵列图案。传统上，使用光刻技术来产生电极阵列并且需要一系列复杂的过程，包括光刻胶旋涂，掩模对准，曝光和显影15,18 ，s ="xref"&gt; 19，20。 在本文中，电极阵列的快速制造通过直接光学图案化来证明。通过光纤激光打标机（1,064nm，20W，90〜120ns脉冲宽度，20〜80kHz脉冲重复频率）部分地除去涂布在玻璃基板上的透明薄膜ITO层，形成四相电极阵列。对角电极之间的距离为150-800μm，可以进行调整以适应实验。四相电极阵列可用于表征和浓缩不同微流体装置15,16,18中的颗粒。为了产生四相电场，电极阵列连接到2通道功能发生器和两个反相器。相邻电极之间的相移设置为90°（对于EROT）或180°（DEP） 15 。 AC信号以0.5至4 V pp电压幅度施加，运行过程中频率范围为100 Hz至5 MHz。将Janus颗粒，金属颗粒和二氧化硅颗粒用作样品以测量其AC电动性质。将颗粒的悬浮液放置在电极阵列的中心区域，并在具有40X，NA 0.6目标的倒置光学显微镜下观察。使用数码相机记录颗粒运动和旋转。 DEP运动被记录在径向远离阵列中心的40至65μm之间的环形区域处，并且EROT被记录在径向远离阵列中心的圆形区域65μm处。颗粒速度和角速度通过粒子跟踪方法测量。粒子质心通过灰度或使用软件的粒子几何来区分。粒子速度和角速度由测量粒子质心的运动。 本文提供了一种快速制造任意图案化电极阵列的简单方法。它介绍了完全或部分涂覆的金属颗粒的制备，可用于不同领域，从生物学到工业应用。

<table><tbody><tr><td>Silica Microsphere-2.34 &amp;micro;m</td><td>Bangs Laboratories</td><td>SS04N</td><td></td></tr><tr><td>Ethyl Alcohol (99.5%)</td><td>KATAYAMA CHEMICAL</td><td>E-0105</td><td></td></tr><tr><td>SYLGARD 184 A&amp;amp;B Silicone Elastomer(PDMS)</td><td>DOW CORNING</td><td></td><td>PDMS&amp;nbsp;</td></tr><tr><td>&amp;nbsp;ITO glass</td><td>Luminescence Technology</td><td>LT-G001</td><td></td></tr><tr><td>Fiber laser marking machine</td><td>Taiwan 3Axle Technology</td><td>TAFB-R-20W</td><td></td></tr><tr><td>&amp;nbsp;2-channel function generator</td><td>Gwinsek</td><td>AFG-2225</td><td></td></tr><tr><td>CMOS camera</td><td>Point Grey</td><td>GS3-U3-32S4M-C</td><td></td></tr><tr><td>Sputter</td><td>JEOL</td><td>JFC-1100E</td><td></td></tr><tr><td>Operational Amplifiers</td><td>Texas Instruments</td><td>LM6361N</td><td>OP invertor&amp;nbsp;</td></tr><tr><td>Ultrasonic Cleaner</td><td>Gui Lin Yiyuan Ultrasonic Machinery Co.</td><td>DG-1</td><td></td></tr><tr><td>Microcentrifuge</td><td>Scientific Specialties, Inc.</td><td></td><td>1.5ml</td></tr><tr><td>Mini Centrifuge</td><td>LMS</td><td>MC-MCF-2360</td><td></td></tr><tr><td>Microscope cover glass</td><td>Marienfeld-Superior</td><td></td><td>18*18mm</td></tr><tr><td>Inverted optical microscope</td><td>Olympus</td><td>OX-71&amp;nbsp;</td><td></td></tr><tr><td>Parafilm</td><td>bemis</td><td></td><td>spacer</td></tr></tbody></table>

preparation of janus particles and alternating current electrokinetic measurements with a rapidly fabricated indium tin oxide electrode array

本文提供了一种制备部分或完全涂覆的金属颗粒并执行电极阵列的快速制造的简单方法，其可以促进微流体装置中的电学实验。 Janus颗粒是在其两侧含有两种不同表面性质的不对称颗粒。为了制备Janus颗粒，通过干燥过程制备单层二氧化硅颗粒。使用溅射装置将金（Au）沉积在每个颗粒的一侧上。完全涂覆的金属颗粒在第二次涂覆工艺之后完成。为了分析Janus粒子的电气表面性质，进行了在实验装置中需要专门设计的电极阵列的交流电（AC）电动力学测量，例如介电电泳（DEP）和电旋转（EROT）。然而，制造电极阵列的传统方法，例如光刻技术，需要一系列的复杂程序。在这里，我们介绍一种灵活的方法来制造设计的电极阵列。通过光纤激光打标机（1,064nm，20W，脉冲宽度为90〜120ns，脉冲重复频率为20〜80kHz）对铟锡氧化物（ITO）玻璃进行图案化，形成四相电极阵列。为了产生四相电场，电极连接到2通道功能发生器和两个反相器。相邻电极之间的相移设置为90°（对于EROT）或180°（对于DEP）。提出了具有四相ITO电极阵列的交流电动测量的代表性结果。

四相电极阵列由光纤激光打标机产生。通过聚焦激光去除涂覆在玻璃上的ITO导电层，形成间隙为160μm的交叉图案， 如图1B所示。 <img alt="图1" class="xfigimg" src="/files/ftp_upload/55950/55950fig1.jpg" /> 图1 :ITO电极的制备。 （ A ）使用光纤激光打标机（1,064nm，20W，9...

Watch this Scientific Journal Video about Preparation of Janus Particles and Alternating Current Electrokinetic Measurements with a Rapidly Fabricated Indium Tin Oxide Electrode Array at JoVE.com

Preparation of Janus Particles and Alternating Current Electrokinetic Measurements with a Rapidly Fabricated Indium Tin Oxide Electrode Array

在本文中，证明了使用快速制造的氧化铟锡（ITO）电极阵列制备部分或完全涂覆的金属颗粒和进行交流电动特性测量的简单方法。

使用快速制造的氧化铟锡电极阵列制备Janus粒子和交流电动势测量

This article provides a simple method to prepare partially or fully coated metallic particles and to perform the rapid fabrication of electrode arrays, ...

preparation-janus-particles-alternating-current-electrokinetic

Universidad de Cartagena UDEC

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JoVE Core

JoVE Journal

Electrical Engineering

Engineering

Unit 1

AC Circuit Analysis

SCIENTISTS IN ACTION

8.1K 次观看.  National Taiwan University. 在本文中，证明了使用快速制造的氧化铟锡（ITO）电极阵列制备部分或完全涂覆的金属颗粒和进行交流电动特性测量的简单方法。 

视频: Preparation of Janus Particles and Alternating Current Electrokinetic Measurements with a Rapidly Fabricated Indium Tin Oxide Electrode Array

Patterning Cells on Optically Transparent Indium Tin Oxide Electrodes

The ability to exercise precise spatial and temporal control over cell-surface interactions is an important prerequisite to the assembly of multi-cellular constructs serving as in vitro mimics of native tissues.  In this study, photolithography and wet etching techniques were used to fabricate individually addressable indium tin oxide (ITO) electrodes on glass substrates.  The glass substrates containing ITO microelectrodes were modified with poly(ethylene glycol) (PEG) silane to make them protein and cell resistive.  Presence of insulating PEG molecules on the electrode surface was verified by cyclic voltammetry employing potassium ferricyanide as a redox reporter molecule.  Importantly, the application of reductive potential caused desorption of the PEG layer, resulting in regeneration of the conductive electrode surface and appearance of typical ferricyanide redox peaks.    Application of reductive potential also corresponded to switching of ITO electrode properties from cell non-adhesive to cell-adhesive. Electrochemical stripping of PEG-silane layer from ITO microelectrodes allowed for cell adhesion to take place in a spatially defined fashion, with cellular patterns corresponding closely to electrode patterns.  Micropatterning of several cell types was demonstrated on these substrates.   In the future, the control of the biointerfacial properties afforded by this method will allow to engineer cellular microenvironments through the assembly of three or more cell types into a precise geometric configuration on an optically transparent substrate.

Non-fouling PEG silane monolayer was desorbed from individually addressable ITO electrodes on glass by application of a reductive potential. Electrochemical stripping of PEG-silane layer from ITO microelectrodes allowed for cell adhesion to take place in a spatially defined fashion, with cellular patterns corresponding closely to electrode patterns.

在光学透明的铟锡氧化物电极的图案细胞

The ability to exercise precise spatial and temporal control over cell-surface interactions is an important prerequisite to the assembly of multi-cellular ...

科研

生物学

AC Electrokinetic Phenomena Generated by Microelectrode Structures

The field of AC electrokinetics is rapidly growing due to its ability to perform dynamic fluid and particle manipulation on the micro- and nano-scale, which is essential for Lab-on-a-Chip applications. AC electrokinetic phenomena use electric fields to generate forces that act on fluids or suspended particles (including those made of dielectric or biological material) and cause them to move in astonishing ways1, 2. Within a single channel, AC electrokinetics can accomplish many essential on-chip operations such as active micro-mixing, particle separation, particle positioning and micro-pattering. A single device may accomplish several of those operations by simply adjusting operating parameters such as frequency or amplitude of the applied voltage. Suitable electric fields can be readily created by micro-electrodes integrated into microchannels. It is clear from the tremendous growth in this field that AC electrokinetics will likely have a profound effect on healthcare diagnostics3-5, environmental monitoring6 and homeland security7.

In general, there are three AC Electrokinetic phenomena (AC electroosmosis, dielectrophoresis and AC electrothermal effect) each with unique dependencies on the operating parameters. A change in these operating parameters can cause one phenomena to become dominant over another, thus changing the particle or fluid behavior. 

It is difficult to predict the behavior of particles and fluids due to the complicated physics that underlie AC electrokinetics. It is the goal of this publication to explain the physics and elucidate particle and fluid behavior. Our analysis also covers how to fabricate the electrode structures that generate them, and how to interpret a wide number of experimental observations using several popular device designs. This video article will help scientists and engineers understand these phenomena and may encourage them to start using AC Electrokinetics in their research.

Manipulating fluids and suspended particles in the micro- and nano-scale is becoming more of a reality as enabling technologies, like AC electrokinetics, continue to develop. Here, we discuss the physics behind AC electrokinetics, how to fabricate these devices and how to interpret the experimental observations.

微电极结构产生的交流电动现象

The field of AC electrokinetics is rapidly growing due to its ability to perform dynamic fluid and particle manipulation on the micro- and nano-scale, ...

Characterizing Electron Transport through Living Biofilms

Here we demonstrate the method of electrochemical gating used to characterize electrical conductivity of electrode-grown microbial biofilms under physiologically relevant conditions.1 These measurements are performed on living biofilms in aqueous medium using source and drain electrodes patterned on a glass surface in a specialized configuration referred to as an interdigitated electrode (IDA) array. A biofilm is grown that extends across the gap connecting the source and drain. Potentials are applied to the electrodes (ES and ED) generating a source-drain current (ISD) through the biofilm between the electrodes. The dependency of electrical conductivity on gate potential (the average of the source and drain potentials, EG = [ED + ES]/2) is determined by systematically changing the gate potential and measuring the resulting source-drain current. The dependency of conductivity on gate potential provides mechanistic information about the extracellular electron transport process underlying the electrical conductivity of the specific biofilm under investigation. The electrochemical gating measurement method described here is based directly on that used by M. S. Wrighton2,3 and colleagues and R. W. Murray4,5,6 and colleagues in the 1980&#39;s to investigate thin film conductive polymers.

A protocol for measuring electrical conductivity of living microbial biofilms under physiologically relevant conditions is presented.

通过活生物膜表征电子传输

Here we demonstrate the method of electrochemical gating used to characterize electrical conductivity of electrode-grown microbial biofilms under ...

化学

A High Performance Impedance-based Platform for Evaporation Rate Detection

This paper describes the method of a novel impedance-based platform for the detection of the evaporation rate. The model compound hyaluronic acid was employed here for demonstration purposes. Multiple evaporation tests on the model compound as a humectant with various concentrations in solutions were conducted for comparison purposes. A conventional weight loss approach is known as the most straightforward, but time-consuming, measurement technique for evaporation rate detection. Yet, a clear disadvantage is that a large volume of sample is required and multiple sample tests cannot be conducted at the same time. For the first time in literature, an electrical impedance sensing chip is successfully applied to a real-time evaporation investigation in a time sharing, continuous and automatic manner. Moreover, as little as 0.5 ml of test samples is required in this impedance-based apparatus, and a large impedance variation is demonstrated among various dilute solutions. The proposed high-sensitivity and fast-response impedance sensing system is found to outperform a conventional weight loss approach in terms of evaporation rate detection.

This paper presents an impedance-based apparatus for evaporation rate detection of solutions. It offers clear advantages over a conventional weight loss approach: a fast response, high-sensitivity detection, a small sample requirement, multiple sample measurements, and easy disassembly for cleaning and reuse purposes.

蒸发速率检测一种基于阻抗高性能平台

This paper describes the method of a novel impedance-based platform for the detection of the evaporation rate. The model compound hyaluronic acid was ...

工程学

Focused Ion Beam Fabrication of LiPON-based Solid-state Lithium-ion Nanobatteries for In Situ Testing

Solid-state electrolytes are a promising replacement for current organic liquid electrolytes, enabling higher energy densities and improved safety of lithium-ion (Li-ion) batteries. However, a number of setbacks prevent their integration into commercial devices. The main limiting factor is due to nanoscale phenomena occurring at the electrode/electrolyte interfaces, ultimately leading to degradation of battery operation. These key problems are highly challenging to observe and characterize as these batteries contain multiple buried interfaces. One approach for direct observation of interfacial phenomena in thin film batteries is through the fabrication of electrochemically active nanobatteries by a focused ion beam (FIB). As such, a reliable technique to fabricate nanobatteries was developed and demonstrated in recent work. Herein, a detailed protocol with a step-by-step process is presented to enable the reproduction of this nanobattery fabrication process. In particular, this technique was applied to a thin film battery consisting of LiCoO2/LiPON/a-Si, and has further been previously demonstrated by in situ cycling within a transmission electron microscope.

Focused Ion Beam Fabrication of LiPON-based Solid-state Lithium-ion Nanobatteries for In Situ Testing

A protocol for the fabrication of electrochemically active LiPON-based solid-state lithium-ion nanobatteries using a focused ion beam is presented.

基于 LiPON 的固态锂离子 Nanobatteries 的聚焦离子束制备方法在原位测试中的研究

Solid-state electrolytes are a promising replacement for current organic liquid electrolytes, enabling higher energy densities and improved safety of ...

In Situ Lithiated Reference Electrode: Four Electrode Design for In-operando Impedance Spectroscopy

Extending operating voltage of Li-ion batteries results in higher energy output from these devices. High voltages, however, may trigger or accelerate multiple processes responsible for long-term performance decay. Given the complexity of physical processes occurring inside the cell, it is often challenging to achieve a full understanding of the root causes of this performance degradation. This difficulty arises in part from the fact that any electrochemical measurement of a battery will return the combined contributions of all components in the cell. Incorporation of a reference electrode can solve part of the problem, as it allows the electrochemical reactions of the cathode and the anode to be individually probed. A variation in the voltage range experienced by the cathode, for example, can indicate alterations in the pool of cyclable lithium ions in the full-cell. The structural evolution of the many interphases existing in the battery can also be monitored, by measuring the contributions of each electrode to the overall cell impedance. Such wealth of information amplifies the reach of diagnostic analysis in Li-ion batteries and provides valuable input to the optimization of individual cell components. In this work, we introduce the design of a test cell able to accommodate multiple reference electrodes, and present reference electrodes that are appropriate for each specific type of measurement, detailing the assembly process in order to maximize the accuracy of the experimental results.

The incorporation of reference electrodes in a Li-ion battery provides valuable information to elucidate degradation mechanisms at high voltages. In this article, we present a cell design that accommodates multiple reference electrodes, along with the assembly steps to assure maximum accuracy of the data obtained in electrochemical measurements.

原位锂化参考电极: 四原位阻抗谱的电极设计

Extending operating voltage of Li-ion batteries results in higher energy output from these devices. High voltages, however, may trigger or accelerate ...

A Method for Systematic Electrochemical and Electrophysiological Evaluation of Neural Recording Electrodes

New materials and designs for neural implants are typically tested separately, with a demonstration of performance but without reference to other implant characteristics.&#160;This precludes a rational selection of a particular implant as optimal for a particular application and the development of new materials based on the most critical performance parameters.&#160;This article develops a protocol for in vitro and in vivo testing of neural recording electrodes.&#160;Recommended parameters for electrochemical and electrophysiological testing are documented with the key steps and potential issues discussed.&#160;This method eliminates or reduces the impact of many systematic errors present in simpler in vivo testing paradigms, especially variations in electrode/neuron distance and between animal models.&#160;The result is a strong correlation between the critical in vitro and in vivo responses, such as impedance and signal-to-noise ratio.&#160;This protocol can easily be adapted to test other electrode materials and designs.&#160;The in vitro techniques can be expanded to any other nondestructive method to determine further important performance indicators.&#160;The principles used for the surgical approach in the auditory pathway can also be modified to other neural regions or tissue.

Different electrode coatings affect neural recording performance through changes to electrochemical, chemical and mechanical properties. Comparison of electrodes in vitro is relatively simple, however comparison of in vivo response is typically complicated by variations in electrode/neuron distance and between animals. This article provides a robust method to compare neural recording electrodes.

对于系统电化学神经记录电极和电生理评价方法

New materials and designs for neural implants are typically tested separately, with a demonstration of performance but without reference to other implant ...

神经科学

Performing In Situ Closed-Cell Gas Reactions in the Transmission Electron Microscope

Gas reactions studied by in situ electron microscopy can be used to capture the real-time morphological and microchemical transformations of materials at length scales down to the atomic level. In situ closed-cell gas reaction (CCGR) studies performed using (scanning) transmission electron microscopy (STEM) can separate and identify localized dynamic reactions, which are extremely challenging to capture using other characterization techniques. For these experiments, we used a CCGR holder that utilizes microelectromechanical systems (MEMS)-based heating microchips (hereafter referred to as &#34;E-chips&#34;). The experimental protocol described here details the method for performing in situ gas reactions in dry and wet gases in an aberration-corrected STEM. This method finds relevance in many different materials systems, such as catalysis and high-temperature oxidation of structural materials at atmospheric pressure and in the presence of various gases with or without water vapor. Here, several sample preparation methods are described for various material form factors. During the reaction, mass spectra obtained with a residual gas analyzer (RGA) system with and without water vapor further validates gas exposure conditions during reactions. Integrating an RGA with an in situ CCGR-STEM system can, therefore, provide critical insight to correlate gas composition with the dynamic surface evolution of materials during reactions. In situ/operando studies using this approach allow&#160;for detailed investigation of the fundamental reaction mechanisms and kinetics that occur at specific environmental conditions (time, temperature, gas, pressure), in real-time, and at high spatial resolution.

Performing In Situ Closed-Cell Gas Reactions in the Transmission Electron Microscope

Here, we present a protocol for performing in situ TEM closed-cell gas reaction experiments while detailing several commonly used sample preparation methods.

在传输电子显微镜中执行 原位 闭电池气体反应

Gas reactions studied by in situ electron microscopy can be used to capture the real-time morphological and microchemical transformations of materials at ...

Precise Electrochemical Sizing of Individual Electro-Inactive Particles

Nanoimpact electrochemistry enables the time-resolved in situ characterization (e.g., size, catalytic activity) of single nanomaterial units, providing a means of elucidating heterogeneities that would be masked in ensemble studies. To implement this technique with redox inactive particles, a solution-phase redox reaction is used to produce a steady-state background current on a disk ultramicroelectrode. When a particle adsorbs onto the electrode, it produces a stepwise reduction in the exposed electrode area, which produces, in turn, a stepwise decrease in the current commensurate with the size of the adsorbing species. Historically, however, nanoimpact electrochemistry has suffered from &#34;edge effects,&#34; in which the radial diffusion layer formed at the circumference of the ultramicroelectrodes renders the step size dependent not only on the size of the particle but also on where it lands on the electrode. The introduction of electrocatalytic current generation, however, mitigates the heterogeneity caused by edge effects, thus improving the measurement precision. In this approach, termed &#34;electrocatalytic interruption,&#34; a substrate that regenerates the redox probe at the diffusion layer is introduced. This shifts the rate-limiting step of the current generation from diffusion to the homogeneous reaction rate constant, thus reducing flux heterogeneity and increasing the precision of particle sizing by an order of magnitude. The protocol described here explains the set-up and data collection employed in nanoimpact experiments implementing this effect for improved precision in the sizing of redox in-active materials.

As an analytical technique, nanoimpact electrochemistry, an increasingly important approach to counting and characterizing nanometer-scale, electro-inactive particles, suffers from poor precision due to the heterogeneous current distributions that arise from its use of ultramicroelectrodes. Outlined here is a generalized approach, termed "electrocatalytic interruption," that enhances precision in such measurements.

单个电活性颗粒的精确电化学定量

Nanoimpact electrochemistry enables the time-resolved in situ characterization (e.g., size, catalytic activity) of single nanomaterial units, providing a ...

Tools for Surface Treatment of Silicon Planar Intracortical Microelectrodes

Intracortical microelectrodes hold great therapeutic potential. But they are challenged with significant performance reduction after modest implantation durations. A substantial contributor to the observed decline is the damage to the neural tissue proximal to the implant and subsequent neuroinflammatory response. Efforts to improve device longevity include chemical modifications or coating applications to the device surface to improve the tissue response. Development of such surface treatments is typically completed using non-functional "dummy" probes that lack the electrical components required for the intended application. Translation to functional devices requires additional consideration given the fragility of intracortical microelectrode arrays. Handling tools greatly facilitate surface treatments to assembled devices, particularly for modifications that require long procedural times. The handling tools described here are used for surface treatments applied via gas-phase deposition and aqueous solution exposure. Characterization of the coating is performed using ellipsometry and x-ray photoelectron spectroscopy. A comparison of electrical impedance spectroscopy recordings before and after the coating procedure on functional devices confirmed device integrity following modification. The described tools can be readily adapted for alternative electrode devices and treatment methods that maintain chemical compatibility.

The present protocol describes tools for handling silicon planar intracortical microelectrodes during treatments for surface modification via gas deposition and aqueous solution reactions. The assembly of the components used to handle the devices throughout the procedure is explained in detail.

用于硅平面皮质内微电极表面处理的工具

Intracortical microelectrodes hold great therapeutic potential. But they are challenged with significant performance reduction after modest implantation ...

使用快速制造的氧化铟锡电极阵列制备Janus粒子和交流电动势测量

摘要

探索更多视频

此视频中的章节

在光学透明的铟锡氧化物电极的图案细胞

微电极结构产生的交流电动现象

通过活生物膜表征电子传输

蒸发速率检测一种基于阻抗高性能平台

基于 LiPON 的固态锂离子 Nanobatteries 的聚焦离子束制备方法在原位测试中的研究

原位锂化参考电极: 四原位阻抗谱的电极设计

对于系统电化学神经记录电极和电生理评价方法

在传输电子显微镜中执行原位闭电池气体反应

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