Reversed Active Sites Boost the Intrinsic Activity of Graphene‐like Cobalt Selenide for Hydrogen Evolution

Abstract

Optimizing the hydrogen adsorption Gibbs free energy (ΔGH) of active sites is essential to improve the overpotential of the electrocatalytic hydrogen evolution reaction (HER). We doped graphene‐like Co0.85Se with sulfur and found that the active sites are reversed (from cationic Co sites to anionic S sites), which contributed to an enhancement in electrocatalytic HER performance. The optimal S‐doped Co0.85Se composite has an overpotential of 108 mV (at 10 mA cm−2) and a Tafel slope of 59 mV dec−1, which exceeds other reported Co0.85Se‐based electrocatalysts. The doped S sites have much higher activity than the Co sites, with a hydrogen adsorption Gibbs free energy (ΔGH) close to zero (0.067 eV), which reduces the reaction barrier for hydrogen production. This work provides inspiration for optimizing the intrinsic HER activity of other related transition metal chalcogenides.

Nanoporous CoP nanowire arrays decorated with carbon‐coated CoP nanoparticles: the role of interfacial engineering for efficient overall water splitting

“…Recently, massive efforts have been made to develop earth-rich HER and OER electrocatalysts with high performance in order to reduce reliance on precious metalbased electrocatalysts. For example, transition metal alloys [10][11][12][13], nitrides [14,15], carbides [16][17][18], phosphides [19][20][21], hydroxide [22], and chalcogenides [23][24][25] have been widely studied. Typically, because of their high intrinsic activity and conductivity, phosphides (TMPs) have traditionally been regarded as excellent potential catalysts for water splitting [21,[26][27][28].…”

Low content Ru-incorporated Pd nanowires for bifunctional electrocatalysis

“…Low-cost renewable energy, such as energy conversion reactions to replace fossil fuels, has long been studied, but fundamental and substantial improvements remain a challenge. 1,2 Moreover, the growing demand for renewable energy increases the need to develop alternative energy and storage systems, such as fuel cells, [3][4][5][6] water splitting, [7][8][9][10] and metal-air batteries. [11][12][13] As part of these systems, catalysis and catalyst design in half-cell reactions, such as the oxygen reduction reaction (ORR), oxygen evolution reaction (OER), and hydrogen evolution reaction (HER), have attracted considerable attention and include fundamental and applied studies.…”

Particle Size Effect of Lanthanum-Modified Bismuth Titanate Ceramics on Ferroelectric Effect for Energy Harvesting

“…Moreover, for high-performance in the device, it has been introduced that surface treatment or controlling the particle size and shape for large surface area. [14][15][16].…”