Name: electrochemical roughening of thin-film platinum macro and microelectrodes
Uploaded: 2019-06-30T12:30:00
Description: Watch this Scientific Journal Video about Electrochemical Roughening of Thin-Film Platinum Macro and Microelectrodes at JoVE.com

The authors would like to thank Lawrence Livermore National Laboratory&#39;s Center for Bioengineering for support during the preparation of this manuscript. Professor Loren Frank is kindly acknowledged for his collaborations with the group that have enabled fabrication and design of the thin-film Pt microarrays discussed in the above work. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344 and funded by Lab Directed Research and Development Award 16-ERD-035. LLNL IM release LLNL-JRNL-762701.

&#8203;CAUTION: Please consult all relevant safety data sheets (SDS) before use. Several of the chemicals used in this protocol are acutely toxic, carcinogenic, oxidizing and explosive when used at high concentrations. Nanomaterials may have additional hazards compared to their bulk counterpart. Please use all appropriate safety practices when carrying out this protocol including the use of engineering controls (fume hood) and personal protective equipment (safety glasses, gloves, lab coat, full length pants, closed-toe ...

<ol>
	<li>Fleischmann, M., Hendra, P. J., McQuillan, A. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Raman+spectra+of+pyridine+adsorbed+at+a+silver+electrode.">Raman spectra of pyridine adsorbed at a silver electrode.</a> Chemical Physics Letters. 26 (2), 163-166 (1974).</li><li>Chung, T., 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=Electrode+modifications+to+lower+electrode+impedance+and+improve+neural+signal+recording+sensitivity.">Electrode modifications to lower electrode impedance and improve neural signal recording sensitivity.</a> Journal of Neural Engineering. 12 (5), 056018 (2015).</li><li>Green, R. A., 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=Laser+patterning+of+platinum+electrodes+for+safe+neurostimulation.">Laser patterning of platinum electrodes for safe neurostimulation.</a> Journal of Neural Engineering. 11 (5), 056017 (2014).</li><li>Arroyo-Curr&#225;s, N., Scida, K., Ploense, K. L., Kippin, T. E., Plaxco, K. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=High+Surface+Area+Electrodes+Generated+via+Electrochemical+Roughening+Improve+the+Signaling+of+Electrochemical+Aptamer-Based+Biosensors.">High Surface Area Electrodes Generated via Electrochemical Roughening Improve the Signaling of Electrochemical Aptamer-Based Biosensors.</a> Analytical Chemistry. 89 (22), 12185-12191 (2017).</li><li>Weremfo, A., Carter, P., Hibbert, D. B., Zhao, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Investigating+the+interfacial+properties+of+electrochemically+roughened+platinum+electrodes+for+neural+stimulation.">Investigating the interfacial properties of electrochemically roughened platinum electrodes for neural stimulation.</a> Langmuir. 31 (8), 2593-2599 (2015).</li><li>Ivanovskaya, A. N., 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=Electrochemical+Roughening+of+Thin-Film+Platinum+for+Neural+Probe+Arrays+and+Biosensing+Applications.">Electrochemical Roughening of Thin-Film Platinum for Neural Probe Arrays and Biosensing Applications.</a> Journal of The Electrochemical Society. 165 (12), G3125-G3132 (2018).</li><li>Cai, W. B., 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=Investigation+of+surface-enhanced+Raman+scattering+from+platinum+electrodes+using+a+confocal+Raman+microscope:+dependence+of+surface+roughening+pretreatment.">Investigation of surface-enhanced Raman scattering from platinum electrodes using a confocal Raman microscope: dependence of surface roughening pretreatment.</a> Surface Science. 406 (1), 9-22 (1998).</li><li>Tykocinski, M., Duan, Y., Tabor, B., Cowan, R. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Chronic+electrical+stimulation+of+the+auditory+nerve+using+high+surface+area+(HiQ)+platinum+electrodes.">Chronic electrical stimulation of the auditory nerve using high surface area (HiQ) platinum electrodes.</a> Hearing Research. 159 (1-2), 53-68 (2001).</li><li>Liu, Y. C., Wang, C. C., Tsai, C. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+electrolytes+used+in+roughening+gold+substrates+by+oxidation-reduction+cycles+on+surface-enhanced+Raman+scattering.">Effects of electrolytes used in roughening gold substrates by oxidation-reduction cycles on surface-enhanced Raman scattering.</a> Electrochemistry Communications. 7 (12), 1345-1350 (2005).</li><li>Liu, Z., Yang, Z. L., Cui, L., Ren, B., Tian, Z. Q. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Electrochemically+Roughened+Palladium+Electrodes+for+Surface-Enhanced+Raman+Spectroscopy:+Methodology,+Mechanism,+and+Application.">Electrochemically Roughened Palladium Electrodes for Surface-Enhanced Raman Spectroscopy: Methodology, Mechanism, and Application.</a> The Journal of Physical Chemistry C. 111 (4), 1770-1775 (2007).</li><li>Rodr&#237;guez, J. M. D., Meli&#225;n, J. A. H., Pe&#241;a, J. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Determination+of+the+Real+Surface+Area+of+Pt+Electrodes.">Determination of the Real Surface Area of Pt Electrodes.</a> Journal of Chemical Education. 77 (9), 1195-1197 (2000).</li><li>Lvovich, V. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Impedance Spectroscopy: Applications to Electrochemical and Dielectric Phenomena. , (2012).</li><li>Tooker, A., 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=Towards+a+large-scale+recording+system:+demonstration+of+polymer-based+penetrating+array+for+chronic+neural+recording.">Towards a large-scale recording system: demonstration of polymer-based penetrating array for chronic neural recording.</a> Conference proceedings - IEEE Engineering in Medicine and Biology Society. 2014, 6830-6833 (2014).</li><li>Tooker, A., 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=Microfabricated+polymer-based+neural+interface+for+electrical+stimulation/recording,+drug+delivery,+and+chemical+sensing+development.">Microfabricated polymer-based neural interface for electrical stimulation/recording, drug delivery, and chemical sensing development.</a> Conference proceedings - IEEE Engineering in Medicine and Biology Society. 2013, 5159-5162 (2013).</li></ol>

The electrochemical roughening of thin-film macroelectrodes and microelectrodes is possible with oxidation-reduction pulsing. This simple approach does require several key elements to nondestructively roughen thin-film electrodes. Unlike foils, roughening of thin metal films may lead to sample destruction if parameters are not properly chosen. Critical parameters of the roughening procedure are pulse amplitude, duration and frequency. Additionally, ensuring electrode cleanliness and perchloric acid purity prior to the pr...

Nearly five decades ago, the first observation of surface enhanced Raman spectroscopy (SERS) occurred on electrochemically roughened silver1. Electrochemical roughening of metal foils is still attractive today because of its simplicity over other roughening methods2,3 and its usefulness in many applications like improving aptamer sensors4, improving neural probes5, and improving adhesion to metal substrates6. Electrochemical roughening methods exist for many bulk metals1,5,7,8,9,10. Until recently, however, there was no report on the application of electrochemical roughening to thin (hundreds of nanometers thick) metal films6, despite the prevalence of microfabricated thin-film metal electrodes in a number of fields.
Established methods to roughen thick platinum (Pt) electrodes5,8 delaminate thin-film Pt electrodes6. By modulating the frequency of the roughening procedure and the electrolyte used for the for the roughening, Ivanovskaya et al. demonstrated Pt thin-film roughening without delamination. That publication focused on using this new approach to increase the surface area of platinum recording and stimulation electrodes on microfabricated neural probes. The roughened electrodes were demonstrated to improve recording and stimulation performance and improve adhesion of electrochemically deposited films and improve biosensor sensitivity6. But this approach also likely improves surface cleaning of microfabricated electrode arrays and enhances the capabilities of thin-film electrodes for other sensor applications (e.g., aptasensors) as well.
The approach to roughen thin-film macroelectrodes (1.2 mm diameter) and microelectrodes (20 &#181;m diameter) is described in the following protocol. This includes preparation of the electrode surface for roughening and how to characterize the roughness of the electrode. These steps are presented along with tips on how to optimize the roughening procedure for other electrode geometries and the most important factors to ensure an electrode is roughened nondestructively.

<table border="0" cellpadding="0" cellspacing="0" style="width:648px;" width="646">
	<tbody>
		<tr height="62">
			<td height="62" style="height:62px;width:223px;">Acetone</td>
			<td style="width:131px;">Fisher Scientific, Sigma Aldrich or similar</td>
			<td style="width:123px;">n/a</td>
			<td style="width:172px;">Laboratory grade</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:223px;">EC-Lab Software</td>
			<td style="width:131px;">Bio-Logic Science Instruments</td>
			<td style="width:123px;">n/a</td>
			<td style="width:172px;">For instrument control and data analysis</td>
		</tr>
		<tr height="125">
			<td height="125" style="height:125px;width:223px;">Leakless Silver/Silver Chloride Reference</td>
			<td style="width:131px;">eDAQ Company, Australia</td>
			<td style="width:123px;">ET069-1</td>
			<td style="width:172px;">Free from chloride anion contamination 
			(or other type of chloride free electrode e.g. Mercury sulfate electrode)</td>
		</tr>
		<tr height="62">
			<td height="62" style="height:62px;width:223px;">Mercury Sulfate &#38; Acid Electrode Kit&#160;</td>
			<td style="width:131px;">Koslow, Scientific Testing Instruments</td>
			<td style="width:123px;">5100A</td>
			<td style="width:172px;">glass, 9mm version</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:223px;">Milipore DI water</td>
			<td style="width:131px;">MilliporeSigma</td>
			<td style="width:123px;">n/a</td>
			<td style="width:172px;">Certified resistivity of 18.2 M&#937;.cm (at 25&#176;C)&#160;</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:223px;">Perchloric acid, 99.9985%</td>
			<td style="width:131px;">Sigma Aldrich</td>
			<td style="width:123px;">311421</td>
			<td style="width:172px;">High Purity</td>
		</tr>
		<tr height="83">
			<td height="83" style="height:83px;width:223px;">Phosphate-buffered saline</td>
			<td style="width:131px;">Teknova</td>
			<td style="width:123px;">P4007</td>
			<td style="width:172px;">10mM PBS with 100mM NaCl, pH 7 
			or similar product from elsewhere</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:223px;">Platinum Wire Auxiliary Electrode (7.5 cm)</td>
			<td style="width:131px;">BASi</td>
			<td style="width:123px;">MW-1032</td>
			<td style="width:172px;">Counter electrode</td>
		</tr>
		<tr height="125">
			<td height="125" style="height:125px;width:223px;">Pt macroelectrodes</td>
			<td style="width:131px;">Lawrence Livermore National Laboratory</td>
			<td style="width:123px;">n/a</td>
			<td style="width:172px;">1.2 mm diameter, 250 nm thick Pt disc electrodes insulated in polyimide. More information in Reference 9.</td>
		</tr>
		<tr height="104">
			<td height="104" style="height:104px;width:223px;">Pt microelectrode arrays</td>
			<td style="width:131px;">Lawrence Livermore National Laboratory</td>
			<td style="width:123px;">n/a</td>
			<td style="width:172px;">20 &#181;m diameter 250 nM thick Pt disc electrodes insulated in polyimide. More information in Reference 9.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:223px;">Sulfuric acid, 99.999%</td>
			<td style="width:131px;">Sigma Aldrich</td>
			<td style="width:123px;">339741</td>
			<td style="width:172px;">High Purity</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:223px;">UV &#38; Ozone Dry Stripper</td>
			<td style="width:131px;">Samco</td>
			<td style="width:123px;">UV-1</td>
			<td style="width:172px;">for cleaning electrodes</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:223px;">VersaSTAT 4 Potentiostat</td>
			<td style="width:131px;">AMETEK, Inc.</td>
			<td style="width:123px;">n/a</td>
			<td style="width:172px;">Good time resolution for pulsing tests</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:223px;">VersaStudio Software</td>
			<td style="width:131px;">AMETEK, Inc.</td>
			<td style="width:123px;">n/a</td>
			<td style="width:172px;">For instrument control</td>
		</tr>
		<tr height="104">
			<td height="104" style="height:104px;width:223px;">VMP-200 Potentiostat&#160;</td>
			<td style="width:131px;">Bio-Logic Science Instruments</td>
			<td style="width:123px;">n/a</td>
			<td style="width:172px;">Low current resolution&#160;option is preferable for measurements with microelectrodes</td>
		</tr>
	</tbody>
</table>

electrochemical roughening of thin-film platinum macro and microelectrodes

This protocol demonstrates a method for electrochemical roughening of thin-film platinum electrodes without preferential dissolution at grain boundaries of the metal. Using this method, a crack free, thin-film macroelectrode surface with up to 40 times increase in active surface area was obtained. The roughening is easy to do in a standard electrochemical characterization laboratory and incudes the application of voltage pulses followed by extended application of a reductive voltage in a perchloric acid solution. The protocol includes the chemical and electrochemical preparation of both a macroscale (1.2 mm diameter) and microscale (20 &#181;m diameter) platinum disc electrode surface, roughening the electrode surface and characterizing the effects of surface roughening on electrode active surface area. This electrochemical characterization includes cyclic voltammetry and impedance spectroscopy and is demonstrated for both the macroelectrodes and the microelectrodes. Roughening increases electrode active surface area, decreases electrode impedance, increases platinum charge injection limits to those of titanium nitride electrodes of same geometry and improves substrates for adhesion of electrochemically deposited films.

A schematic showing the voltage application for roughening both macroelectrodes and microelectrodes is shown in Figure 2. Optical microscopy can be used to visualize the difference in the appearance of a roughened macroelectrode (Figure 3) or microelectrode (Figure 4). In addition, electrochemical characterization of the Pt surface using impedance spectroscopy and cyclic voltammetry can readily show ...

Watch this Scientific Journal Video about Electrochemical Roughening of Thin-Film Platinum Macro and Microelectrodes at JoVE.com

Electrochemical Roughening of Thin-Film Platinum Macro and Microelectrodes

This protocol demonstrates a method for electrochemical roughening of thin-film platinum electrodes without preferential dissolution at grain boundaries. The electrochemical techniques of cyclic voltammetry and impedance spectroscopy are demonstrated to characterize these electrode surfaces.

This protocol demonstrates a method for electrochemical roughening of thin-film platinum electrodes without preferential dissolution at grain boundaries ...

Research

JoVE Journal

Chemistry

Dynamic Electrochemical Measurement of Chloride Ions

This protocol describes the dynamic measurement of chloride ions using the transition time of a silver silver chloride (Ag/AgCl) electrode. Silver silver ...

Electrochemical Impedance Spectroscopy as a Tool for Electrochemical Rate Constant Estimation

Electrochemical impedance spectroscopy (EIS) was used for advanced characterization of organic electroactive compounds along with cyclic voltammetry (CV). ...

Synthesis of Platinum-nickel Nanowires and Optimization for Oxygen Reduction Performance

Platinum-nickel (Pt-Ni) nanowires were developed as fuel cell electrocatalysts, and were optimized for the performance and durability in the oxygen ...

Chemical Synthesis of Porous Barium Titanate Thin Film and Thermal Stabilization of Ferroelectric Phase by Porosity-Induced Strain

Barium titanate (BaTiO3, hereafter BT) is an established ferroelectric material first discovered in the 1940s and still widely used because of its ...

Gold Nanoparticle Modified Carbon Fiber Microelectrodes for Enhanced Neurochemical Detection

For over 30 years, carbon-fiber microelectrodes (CFMEs) have been the standard for neurotransmitter detection. Generally, carbon fibers are aspirated into ...

Asymmetric Thermoelectrochemical Cell for Harvesting Low-grade Heat under Isothermal Operation

Low-grade heat is abundantly available in the environment as waste heat. The efficient conversion of low-grade heat into electricity is very difficult. We ...

The Effect of Anodization Parameters on the Aluminum Oxide Dielectric Layer of Thin-Film Transistors

Aluminum-oxide (Al2O3) is a low cost, easily processable and high dielectric constant insulating material that is particularly appropriate for use as the ...

Fabrication of Thin Film Silver/Silver Chloride Electrodes with Finely Controlled Single Layer Silver Chloride

This paper aims to present a protocol to form smooth and well-controlled films of silver/silver chloride (Ag/AgCl) with designated coverage on top of thin ...

Probing Surface Electrochemical Activity of Nanomaterials using a Hybrid Atomic Force Microscope-Scanning Electrochemical Microscope (AFM-SECM)

Probing Surface Electrochemical Activity of Nanomaterials using a Hybrid Atomic Force Microscope-Scanning Electrochemical Microscope AFM-SECM

Scanning electrochemical microscopy (SECM) is used to measure the local electrochemical behavior of liquid/solid, liquid/gas and liquid/liquid interfaces. ...

A Salt-Templated Synthesis Method for Porous Platinum-based Macrobeams and Macrotubes

The synthesis of high surface area porous noble metal nanomaterials generally relies on time consuming coalescence of pre-formed nanoparticles, followed ...