Activating Basal Planes and S‐Terminated Edges of MoS₂ toward More Efficient Hydrogen Evolution

Abstract

Molybdenum disulfide (MoS2) has been considered as a promising alternative to platinum (Pt)‐based catalyst for hydrogen evolution reaction (HER) due to its low cost and high catalytic activity. However, stable 2H phase of MoS2 (2H‐MoS2) exhibits low catalytic activity in HER due to the inert basal plane and S‐edge. Thus, to exploit the basal plane and S‐edge for additional electrocatalytic activity, a facile strategy is developed to prepare P‐doped 2H‐MoS2 film on conductive substrate via low‐temperature heat treatment. Due to the inherent difficulty of P‐doping into MoS2 crystal structure, oxygen (O)‐doping is utilized to aid the P‐doping process, as supported by the first‐principles calculations. Interestingly, P‐doping could dramatically reduce Mo valence charge, which results in the functionalization of the inert MoS2 basal plane and S‐edge. In agreement with simulation results, P‐doped 2H‐MoS2 electrode exhibits enhanced catalytic performance in H2 generation with low onset potential (130 mV) and small Tafel slope of 49 mV dec−1. The enhanced catalytic performance arises from the synergistic effect of the activated basal plane, S‐edge, and Mo‐edge sites, leading to favorable hydrogen adsorption energies. Most importantly, improved cyclic stability is achieved, which reveals chemically inert properties of P‐doped 2H‐MoS2 in acidic electrolyte.

Single Atoms and Clusters Based Nanomaterials for Hydrogen Evolution, Oxygen Evolution Reactions, and Full Water Splitting

“…Also, the Δ G H* of Ni‐MoS 2 (–0.07 eV) was much lower than pristine MoS 2 (0.60 eV), which shows that the combination of intermediates H* into H 2 can occur spontaneously in thermodynamics. Similarly, Xue et al activated the S‐edge and basal plane of 2H‐MoS 2 by P doping . Due to the difficulty of P doping into the crystal structure of MoS 2 , oxygen codoping was utilized to dope P successfully into the basal plane of 2H‐MoS 2 .…”

Dual‐Native Vacancy Activated Basal Plane and Conductivity of MoSe2 with High‐Efficiency Hydrogen Evolution Reaction

“…[27] P dopants might lead to phase separation, [28] and the stabilize the P dopants in MoS 2 needs oxygen co-doping. [29] Very recently, Li et al demonstrated that the intrinsic electrocatalytic activity of 2H-MoS 2 basal plane could be activated by introducing of S-vacancy and strain, providing a new strategy to activate the HER inert basal plane sites in MoS 2 catalysts. [30] Recently, MoSe 2 also has aroused much attention in HER catalysts due to its metallic nature compared with semiconducting MoS 2 .…”

“…N dopants can only activate the inert S‐edge rather than basal plane . P dopants might lead to phase separation, and the stabilize the P dopants in MoS 2 needs oxygen co‐doping . Very recently, Li et al demonstrated that the intrinsic electrocatalytic activity of 2H‐MoS 2 basal plane could be activated by introducing of S‐vacancy and strain, providing a new strategy to activate the HER inert basal plane sites in MoS 2 catalysts …”

MoFe‐Codoped Ni3S2/Ni(OH)2 Nanosheets with Large Sample Size toward High‐Performance Oxygen Evolution

“…[16] The binding energies of Mo 3d 3/2 and Mo 3d 5/2 are 235.6 and 232.4 eV, respectively, attributed to Mo 6þ in the form of MoO 4 2À . [17] Compared with the Mo 4þ in MoS 2 , [18] the doped Mo has a much higher binding energy, suggesting that Mo prefers to incorporate into the Ni 3 S 2 /Ni(OH) 2 composites with high oxidization states. In Figure 3d, the binding energy of 163.6 eV corresponds to the S 2À 2p 1/2 of Ni 3 S 2 .…”