The true functionality of a current collector employed in electrochemical cells is to ensure a low- resistance steady electrons flow between the cell and instrumentation without involving in any local electrochemical reactions of the electrode. In this study, we investigated the effect of curing temperature of a common current collector, silver, on the polarization area specific resistance (ASR) of a cathode. The results explicitly showed that at least one order of magnitude lower ASR for a cathode with Ag cured at 800°C than that cured at 650°C of the same cathode configuration. Microscopic analysis of the 800°C-cured cells revealed a deep penetration and abundant distribution of Ag into the cathode/electrolyte interfacial region. These finely dispersed and highly conductive Ag particles/agglomerates are ORR (oxygen reduction reaction)-active, thus engaging in the local electrochemical reaction and overshadowing the true properties of the cathode under investigation. Based on these results, we call for caution when using Ag as a current collector for electrochemical measurements, particularly at a temperature ≥650°C.
Published in ECS Electrochemistry Letters, Volume 2, Issue 1, 2012, pages F4-F7.
©ECS Electrochemistry Letters 2012, The Electrochemcial Society.
© The Electrochemical Society, Inc. 2012. All rights reserved. Except as provided under U.S. copyright law, this work may not be reproduced, resold, distributed, or modified without the express permission of The Electrochemical Society (ECS). The archival version of this work was published in ECS Electrochemistry Letters.
Publisher’s Version: http://dx.doi.org/10.1149/2.010301eel
Gong, Y., Qin, C., & Huang, K. (November 6, 2012). Can Silver Be a Reliable Current Collector for Electrochemical Tests? ECS Electrochemistry Letters, 2 (1), F4 – F7. http://dx.doi.org/10.1149/2.010301eel