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

Abstract

The exploration of non-precious catalysts for the hydrogen evolution reaction (HER) remains critical in the commercialization of electrochemical energy storage and conversion technologies. Two-dimensional transitional metal carbides called MXenes have been found to have great potential as electrocatalysts for HER. In this work, we synthesize two Mo based MXenes: Mo1.33CTz and Mo2CTz and measure their HER activity and operational durability. The ordered divacancies on the basal planes of Mo1.33CTz cause a marked decrease in HER activity compared to Mo2CTz. The stoichiometry and atomic surface structure of MXenes is found to be critically important for catalytic activity while having less of an impact on operational durability. This work provides insight for the development active 2D materials for HER and other technologically relevant electrochemical reactions.

On a Two-Dimensional MoS2/Mo2CTx Hydrogen Evolution Catalyst Obtained by the Topotactic Sulfurization of Mo2CTx MXene

“…18,29 Among the different MXenes synthesized to date, Mo 2 CT x is one of the most promising for HER. 30,31 The choice of this MXene as HER catalyst support was also made, instead of the more classical carbon, for three reasons: (i) it is more conductive, (ii) it is more electroactive, allowing to use it as co-catalyst and (iii) the MoS 2 /Mo 2 CT x composite can be produced, as shown herein, in a one-step process.…”

One MAX phase, different MXenes: A guideline to understand the crucial role of etching conditions on Ti3C2Tx surface chemistry

“…MXenes are among the newest and largest family of 2D materials with demonstrated applications in diverse fields such as electromagnetic interference shielding [1], transparent conductive films [2], wireless communication [3], hydrogen and oxygen electrocatalysis [4][5][6][7], supercapacitors [8], batteries [8], catalysis [9], photocatalysis [10], hydrogen storage [11], gas and biosensors [12,13], electromechanical actuators [14], pH and humidity sensor [15,16], nanomedicine [17] or gas and liquid separation and purification [18,19]. The properties and potential applications of these materials have been the subject of several recent reviews [20][21][22][23][24][25].…”

Edge Capping of 2D‐MXene Sheets with Polyanionic Salts To Mitigate Oxidation in Aqueous Colloidal Suspensions

“…[4] Since the initial discovery of Ti 3 C 2 T z ,w hich is by far the most studied MXene,m ore than 30 new ones have been discovered. [4] MXenes have shown promise in numerous applications such as EMI shielding, [10] energy storage, [11] gas sensing, [12] water purification, [13] and as ac atalyst for hydrogen evolution reactions, [14] among many others.…”