Decoding Electrocatalysis: Transforming Aluminum-Clad TLC Plates into Potash Alum for Hydrogen Evolution Exploration

Abstract

This work deals with using a waste aluminum-based TLC plate to prepare crystalline potash alum, which is subsequently activated for the study of hydrogen evolution reaction in alkaline KOH. The structural and morphological characterization of the synthesized potash alum (PA) has been assessed with powder X-ray diffraction and thermogravimetry analysis. Scanning electron micrographs reveal the morphology of the activated potash alum. The heterogeneous electrocatalytic HER activity in 1 M KOH attributes a moderate electrocatalytic efficiency for activated potash alum (APA) in the light of onset potentials, Faradic efficiency, double-layer capacitance, electrochemically activated surface area, and number of active sites. However, the electrocatalyst APA is a pre-catalyst as it undergoes a significant structural transformation under the electrochemical operation, leading to Al2O3 nanoparticles being the active catalyst for hydrogen production. Possibly, the chemical inertness of the Al2O3 induces a limitation in the local vicinity for the synergistic effect for facile electron transport in alkaline KOH.