Microwave-Assisted Reactant-Protecting Strategy toward Efficient MoS₂ Electrocatalysts in Hydrogen Evolution Reaction

Abstract

The exposure of rich active sites is crucial for MoS2 nanocatalysts in efficient hydrogen evolution reaction (HER). However, the active (010) and (100) planes tend to vanish during preparation because of their high surface energy. Employing the protection by thiourea (TU) reactant, a microwave-assisted reactant-protecting strategy is successfully introduced to fabricate active-site-rich MoS2 (AS-rich MoS2). The bifunctionality of TU, as both a reactant and a capping agent, ensures rich interactions for the effective protection and easy exposure of active sites in MoS2, avoiding the complicated control and fussy procedure related to additional surfactants and templates. The as-obtained AS-rich MoS2 presents the superior HER activity characterized by its high current density (j = 68 mA cm(-2) at -300 mV vs RHE), low Tafel slope (53.5 mV dec(-1)) and low onset overpotential (180 mV), which stems from the rich catalytic sites and the promoted conductivity. This work elucidates a feasible way toward high performance catalysts via interface engineering, shedding some light on the development of emerging nanocatalysts.

Structural Design and Electronic Modulation of Transition‐Metal‐Carbide Electrocatalysts toward Efficient Hydrogen Evolution

“…Facet engineering of catalysts has become an important strategy for fine‐tuning the physicochemical properties and thus optimizing reactivity and selectivity . As for nanosized MoS 2 , the surface engineering was devoted to preferentially exposing highly active MoS 2 (100) and (010) for efficient electrocatalysis . Analogously, 2D TMCs fabricated via CVD or exfoliation from MAX (MXenes) can be regarded as modeling catalysts to identify the HER activity on specific crystallographic atomic planes.…”

Interlayer Nanoarchitectonics of Two‐Dimensional Transition‐Metal Dichalcogenides Nanosheets for Energy Storage and Conversion Applications

“…[79] Gao and coworkers reported a microwave-assisted hydrothermal route to synthesize thiourea-caped MoS 2 nanosheets with an expanded interlayer spacing of 0.92 nm. [80] Wang and co-workers reported intercalation of different species of polyvinyl pyrrolidone (PVP), ethylene diaminetrimolybdate (EDA) and amorphous carbon into nanostructures of MoS 2 by a hydrothermal route, achieving expanded interlayer spacings of 0.705, 1.002 and 1.159 nm, respectively. [75] Chen and co-workers reported a glucose-assisted hydrothermal route followed with annealing to synthesis graphene-like MoS 2 /amorphous carbon with an interlayer spacing as large as 1.18 nm.…”

Ultrafine Pt Nanoparticle‐Decorated Pyrite‐Type CoS2Nanosheet Arrays Coated on Carbon Cloth as a Bifunctional Electrode for Overall Water Splitting

“…Both peaks are slightly shifted to lower binding energies relative to the binding energies of the peaks of commercial Pt/C, indicating that the electronic structure of Pt was modified by the presence of a CoS 2 substrate. [23] The higher intensity of the shakeup satellite at 168.7 eV (marked as Sat.) The oxidation states are quantitatively corroborated by the fitted ratios of Co 3+ to Co 2+ in Pt-CoS 2 /CC (0.77) and CoS 2 /CC (0.55, Table S1, Supporting Information).…”