Superaerophobic/superhydrophilic surfaces as advanced electrocatalysts for the hydrogen evolution reaction: a comprehensive review

Abstract

High-efficiency electrocatalysts are crucial for a fossil fuel-free future. Although many strategies have been proposed to boost the electrocatalysts' performance, efficient and cost-effective methods are rare. Recently, hydrogen (H₂) and oxygen (O₂) production via water electrolysis has seen increased interest. To efficiently produce using electrochemical water splitting (EWS), there are many resistances in electrolysis systems that must be reduced. One of the major resistances in the system that dramatically reduces the system's efficiency is the adhesion of evolved gas bubbles to the surface of the electrode. Blocked active sites occur when bubbles adhere to the surface. As a result, a decrease in mass transfer ability can be expected, which can severely damage the gas production efficiency. One of the main techniques that is able to reduce bubble adhesion is to make electrocatalysts with superaerophobic and/or superhydrophilic surfaces. These surfaces can be created using different morphologies, such as nanosheets, nanotubes, and nanowires. In this review, in addition to getting acquainted with the mechanism of separation of bubbles from the surface and the application of superaerophobic/superhydrophilic surfaces as efficient electrocatalysts for the hydrogen evolution reaction and other electrochemical reactions, the latest research in this field will be reviewed.