Study on surface modification of AB5-type alloy electrode with polyaniline by electroless deposition

A new polyaniline (PANI)-coated technique was adopted for a AB(5)-type alloy (La0.64Ce0.25Pr0.03Nd0.08Ni4.19Mn0.31Co0.42Al0.23) in order to improve its electrochemical and kinetic properties. FE-SEM observation and FT-IR analysis results revealed that the PANI electroless deposited to the surface of alloy particles. Through the PANI-coating the initial discharge capacity increased from 299 to 331 mAh/g and the high rate discharge ability (HRD) increased from 8.5 to 45.0% at discharge current density of 1440 mA/g. For kinetic properties, linear polarization, EIS, anodic polarization and cyclic voltammetry measurements suggested that charge-transfer resistance decreased and the hydrogen absorption rate of the alloys increased after PANI-coating. (C) 2010 Elsevier Ltd. All rights reserved.