The Effect of the 3D Nanoarchitecture and Ni‐Promotion on the Hydrogen Evolution Reaction in MoS₂/Reduced GO Aerogel Hybrid Microspheres Produced by a Simple One‐Pot Electrospraying Procedure

Abstract

The transition toward renewable energy sources requires low‐cost, efficient, and durable electrocatalysts for green H2 production. Herein, an easy and highly scalable method to prepare MoS2 nanoparticles embedded in 3D partially reduced (pr) graphene oxide (GO) aerogel microspheres (MoS2/prGOAMs) with controlled morphology and composition is described. Given their peculiar center‐diverging mesoporous structure, which allows easy access to the active sites and optimal mass transport, and their efficient electron transfer facilitated by the intimate contact between the MoS2 and the 3D connected highly conductive pr‐GO sheets, these materials exhibit a remarkable electrocatalytic activity in the hydrogen evolution reaction (HER). Ni atoms, either as single Ni atoms or NiO aggregates are then introduced in the MoS2/prGOAMs hybrids, to facilitate water dissociation, which is the slowest step in alkaline HER, producing a bifunctional catalyst. After optimization, Ni‐promoted MoS2/prGOAMs obtained at 500 °C reach a remarkable η10 (overpotential at 10 mA cm−2) of 160 mV in 1 m KOH and 174 mV in 0.5 m H2SO4. Moreover, after chronopotentiometry tests (15 h) at a current density of 10 mA cm−2, the η10 value improves to 147 mV in alkaline conditions, indicating an exceptional stability.

Amorphous MoS2 Decorated Ni3S2 with a Core–shell Structure of Urchin‐Like on Nickel‐Foam Efficient Hydrogen Evolution in Acidic and Alkaline Media

“…For comparison, the performance of Ni 3 S 2 -NF, bare NF and commercial Pt/C were investigated under identical conditions. As depicted in Figure 5a,b, the Pt/C electrode demonstrated the S3 (Supporting Information), [35][36][37][38][39][40][41][42][43][44][45][46][47][48][49][50] has the lowest charge transfer resistance, indicating that the presence of Ni 3 S 2 can significantly improve the electron transfer rate at the heterogeneous interface.…”

Spatial Relation Controllable Di‐Defects Synergy Boosts Electrocatalytic Hydrogen Evolution Reaction over VSe2 Nanoflakes in All pH Electrolytes

“…According to the literature, the HER activity is higher in acidic media, which can be attributed to the initial splitting of the HOH bond in the Volmer step provides suitable H ad for the following steps and is considered the rate-determining step. [54][55][56] Also, superior HER performance was obtained over various VSe 2 -based electrodes in an acidic medium (0.5 m H 2 SO 4 ) than that in alkaline solution (1.0 m KOH). However, in the unamiable alkaline electrolyte, the electroactivity of V 0.8 Mo 0.2 Se 2−x was significantly improved to a level similar to that of Pt/C (20 wt.%), likely because sufficient electrons migrated to the surrounding di-defect area, which accelerated the Volmer adsorption step (H 2 O + e − → H ad + OH − ).…”

CoS2-MoS2 Nanoflower Arrays for Efficient Hydrogen Evolution Reaction in the Universal pH Range

“…Given the global ever-growing energy crisis and serious environmental problems, numerous researches have focused on the development of new and clean energy sources to replace the commonly used fossil fuels, , among which hydrogen energy is a good choice. , In recent years, electrocatalytic water splitting has drawn great attention because it is one of the easiest and most effective methods to obtain hydrogen energy. , Traditional Pt-based metal electrocatalysts show excellent activity in the hydrogen evolution reaction (HER), but the scarcity and expense of Pt seriously hinder their commercial applications. Therefore, researchers are eager to develop cost-effective nonnoble metal HER electrocatalysts with high catalytic activity.…”