Electrocatalysis of Selective Chlorine Evolution Reaction: Fundamental Understanding and Catalyst Design

The electrochemical chlorine evolution reaction (CER) is an important electrochemical reaction and has been widely used in chlor–alkali electrolysis, on-site generation of ClO−, and Cl2-mediated electrosynthesis. Although precious metal-based mixed metal oxides (MMOs) have been used as CER catalysts for more than half a century, they intrinsically suffer from a selectivity problem between the CER and parasitic oxygen evolution reaction (OER). Hence, the design of selective CER electrocatalysts is critically important. In this review, we provide an overview of the fundamental issues related to the electrocatalysis of the CER and design strategies for selective CER electrocatalysts. We present experimental and theoretical methods for assessing the active sites of MMO catalysts and the origin of the scaling relationship between the CER and the OER. We discuss kinetic analysis methods to und…