Ni‐Activated Transition Metal Carbides for Efficient Hydrogen Evolution in Acidic and Alkaline Solutions

Abstract

Transition metal carbides (TMCs) feature high catalytic activity and superior stability for the hydrogen evolution reaction (HER). However, their platinum‐like HER catalytic performance is heavily hindered, due to their strong interaction with hydrogen. Herein, Ni activation of TMCs (M = V, Fe, Cr, and Mo) is proposed through introducing adsorbed nickel atoms on the TMC surface (Ni/TMC). In both acidic and alkaline solutions, a sharp decrease of both overpotentials and Tafel slopes of the Ni/TMC catalysts for HER is achieved. At 10 mA cm−2, the overpotentials of the Ni/vanadium carbide (VC) and Ni/Fe3C catalysts are 128 and 93 mV in 1 m KOH, 111 and 112 mV in 0.5 m H2SO4, respectively. Even at 150 mA cm−2, they exhibit the overpotentials of as low as 270 and 291 mV, respectively. In the alkaline solutions, the performance of these Ni/TMC catalysts is even superior to a Pt/C catalyst. As confirmed from density functional theory calculations and X‐ray absorption fine structure analysis, such adsorbed Ni atoms effectively optimize the d‐electron structure and improve HER performance. As a versatile strategy, this work provides a universal route to activate TMCs for highly efficient HER in different media.

Balance Effect: A Universal Strategy for Transition Metal Carbides to Enhance Hydrogen Evolution

“…These Tafel slopes imply that the HER mechanism on the Mo 2 C@NG/CNT electrocatalyst follows a Volmer–Heyrovsky route in both alkaline and acid media. [ 18 ] Beyond these experiments, the HER performance of the Mo 2 C@N‐doped CNT electrocatalyst was evaluated and further compared with that of the Mo 2 C@NG/CNT electrocatalyst. The overpotential and Tafel slope of the Mo 2 C@N‐doped CNT electrocatalyst are larger than those of the Mo 2 C@NG/CNT electrocatalyst in both 0.5 m H 2 SO 4 (Figure S13a,b, Supporting Information) and 1 m KOH (Figure S13c,d, Supporting Information).…”

Recent advances in non-precious group metal-based catalysts for water electrolysis and beyond

“…9c). 75 The Δ G H* values for the (100) and (111) planes of Ni ads site were 0.161 and 0.254 eV, respectively, which were much lower than that of C and V sites, indicating an active Ni site in Ni-VC. Recently, Mu et al fabricated Ni-Ni 3 C heterostructures to adjust the adsorption of H*.…”

Mn, P co-doped sharp-edged Mo2C nanosheets anchored on porous carbon for efficient electrocatalytic hydrogen evolution

“…Fortunately, transition metal-based electrocatalysts with high availability, excellent stability and prominent activity have been developed over the past few decades. 4–10…”