Electrochemically Synthesized Nanoporous Molybdenum Carbide as a Durable Electrocatalyst for Hydrogen Evolution Reaction

Abstract

Demands for sustainable production of hydrogen are rapidly increasing because of environmental considerations for fossil fuel consumption and development of fuel cell technologies. Thus, the development of high‐performance and economical catalysts has been extensively investigated. In this study, a nanoporous Mo carbide electrode is prepared using a top‐down electrochemical process and it is applied as an electrocatalyst for the hydrogen evolution reaction (HER). Anodic oxidation of Mo foil followed by heat treatment in a carbon monoxide (CO) atmosphere forms a nanostructured Mo carbide with excellent interconnections, and these structural characteristics lead to high activity and durability when applied to the HER. Additionally, characteristic behavior of Mo is observed; metallic Mo nanosheets form during electrochemical anodization by exfoliation along the (110) planes. These nanosheets are viable for chemical modification, indicating their feasibility in various applications. Moreover, the role of carbon shells is investigated on the surface of the electrocatalysts, whereby it is suggested that carbon shells serve as a mechanical barrier against the oxidative degradation of catalysts that accompanies unavoidable volume expansion.

Stoichiometry and surface structure dependence of hydrogen evolution reaction activity and stability of MoxC MXenes

“…In both cases, the relative area of the latter peak increases with cycling, indicating a slow oxidation of the MXenes during HER ADT cycling. This conclusion is consistent with that of Kang et al who also observed oxidation of commercial Mo2C powders during HER 41 . Table 1 summarizes the XPS peak fitting results.…”

Two-Dimensional Sandwich-Structured Mesoporous Mo2C/Carbon/Graphene Nanohybrids for Efficient Hydrogen Production Electrocatalysts

“…XRD spectra (Figure a) display exactly the characteristic diffraction peaks attributed to β-Mo 2 C crystals (JCPDS, no. 35-0787), − thus confirming the formation of Mo 2 C. The strongest signal located at 39.1° corresponds to the (101) crystal planes with an interplanar distance of 0.23 nm, ,,− which is well in accordance with the HRTEM result. The graphitization of the as-prepared samples was investigated by Raman spectroscopy.…”

Neural Network Inspired Design of Highly Active and Durable N-Doped Carbon Interconnected Molybdenum Phosphide for Hydrogen Evolution Reaction

“…In the past few decades, a large number of non-noble metal catalysts, such as transition-metal sulfides, ,− carbides, − phosphides, − selenides, − nitrides, − and metal alloys, , have been investigated as the potential electrocatalysts for HER. Among them, molybdenum phosphides are one of the most extensively reported HER catalysts, because of the platinum-like electronic structures, acceptable electroconductivity, low cost, efficient catalytic activity, and remarkable durability over all pH range.…”