Palladium-coated polyaniline nanofiber electrode as an efficient electrocatalyst for hydrogen evolution reaction

Abstract

In this study, polyaniline (PANI) with abundant protonated regions was used for the first time as a palladium (Pd) support for enhanced performance in hydrogen evolution reaction (HER). For this purpose, the hierarchical Pd@PANI nanofiber electrode was easily synthesized by electrochemical polymerization of aniline on Au followed by potential-controlled electrochemical deposition of Pd nanoclusters on the PANI. The reported catalyst was characterized by X-ray diffraction, X-ray photoelectron spectroscopy, and field-emission scanning electron microscopy. Linear sweep voltammetry analysis was performed to evaluate the HER performance. Ion transfer behavior was investigated using electrochemical impedance spectroscopy analysis. The electrochemical tests show that the Pd@PANI/Au electrode has a low overpotential of similar to 60 mV at 10 mA cm(-2) and a small Tafel slope of 35 mV dec(-1) for HER in acidic media, with high catalytic activity and stability. These features will make the Pd@PANI/Au a promising candidate as a high-performance electrocatalyst for HER applications. (C) 2021 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.