A selective and efficient precious metal-free electrocatalyst for chlorine evolution reaction: An experimental and computational study

Abstract

Chlor-Alkali (CA) process benefits from chlorine evolution reaction (ClER) over various precious metal oxides electrocatalysts. This study introduces a novel precious metal-free Ti 0:35 V 0:35 Sn 0:25 Sb 0.05 -oxide electrocatalyst which selectively conducts the reaction pathway towards ClER with a high faradaic current efficiency of ~88%. The electrocatalyst and its electrochemical activity were scrutinized by various techniques such as field-emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), and linear scanning voltammetry (LSV). A decent overpotential difference (DE) between oxygen evolution reaction (OER) and chlorine evolution reactions (ClER) was attributed to the reasonable design of the electrocatalyst composite. Namely, the geometric structure and surface properties of the synthesized electrocatalyst, as well as the associated electrochemical selectivity was tuned by incorporation of vanadium pentoxide, antimony and tin oxide in the electrocatalyst material. In addition, the electronic properties of the synthesized electrocatalysts including band structure and the corresponding electron density were studied by density functional theory (DFT) calculations. • A cost-effective Ti 0:35 V 0:35 Sn 0:25 Sb 0.05 -oxide electrocatalyst was synthesized. • The developed electrocatalyst was tuned towards chlorine evolution reaction. • Preferred chlorine evolution was resulted rather than oxygen evolution reaction. • The electronic structure of the developed electrocatalysts was explored by DFT. • The presence of vanadium oxide could lower the band gap of the electrocatalyst.