MAX and MAB Phases: Two-Dimensional Layered Carbide and Boride Nanomaterials for Electrochemical Applications

Electrochemical and electrocatalytic properties of a class of layered materials known as MAX and MAB phases have yet to gain interest in the scientific community. Herein, electrochemical and toxicity studies of six MAX and MAB phases (Ti2AlC, Ti2AlN, Ti3AlC2, Ti3SiC2, Cr2AlB2, and MoAIB) were explored. The materials were found to possess high heterogeneous electron transfer (HET) rates, enhanced electrochemical sensing of ascorbic acid and uric acid, and promising electrocatalytic performances toward hydrogen evolution reaction (HER) and oxygen reduction reaction (ORR). MAB phases possessed better electrochemical properties than did MAX phases. In addition, in vitro cytotoxicity studies toward various human cells found near negligible toxicity toward the cells tested deeming them safe for handling and biocompatible for future biological applications. Therefore, MAX and MAB phases can be regarded as safe layered materials for potential electrochemical applications.