Metallic group VIB transition metal dichalcogenides (1T-TMDs) have attracted great interest because of their outstanding performance in electrocatalysis, supercapacitors, batteries, and so on, whereas the strict fabrication conditions and thermodynamical metastability of 1T-TMDs greatly restrict their extensive applications. Therefore, it is significant to obtain stable and high-concentration 1T-TMDs in a simple and large-scale strategy. Herein, we report a facile and large-scale synthesis of high-concentration 1T-TMDs via an ionic liquid (IL) assisted hydrothermal strategy, including 1T-MoS2 (the obtained MoS2 sample was denoted as MoS2-IL), 1T-WS2, 1T-MoSe2, and 1T-WSe2. More importantly, we found that IL can adsorb on the surface of 1T-MoS2, where the steric hindrance, π–π stacking, and hydrogen bonds of ionic liquid collectively induce the formation of the 1T-MoS2. In addition, DFT calculation reveals that electrons are transferred from [BMIM]­SCN (1-butyl-3-methylimidazolium thiocyanate) to 1T-MoS2 layers by hydrogen bonds, which enhances the stability of 1T-MoS2, so the MoS2-IL performs with high stability for 180 days at room temperature without obvious change. Furthermore, the MoS2-IL exhibits excellent HER performance with an overpotential of 196 mV at 10 mA cm–2 in acid conditions.

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Owing to the unique conductivity and catalytic activity, bimetallic nitrides are regarded as applicable catalysts for oxygen evolution reaction (OER), but practical progress is restricted due to that fact that the synthesis of bimetallic nitrides is complicated and the stability in strong alkaline electrolytes is insufficient. Herein, to improve performance with a synergistic effect, the ternary Ni 3 Mo 3 N-MoO 2 -NiO nanoparticles catalyst (NMN-MO-NO) and its derivatives are fabricated by pyrolyzing the Ni−Mo urea precursor at 800 °C in Ar. The nest-like NMN-MO-NO is composed of particles with a diameter of about 40 nm, including an abundant contact area. As-prepared samples are conducted in the OER measurements, in which NMN-MO-NO exhibited the best performance. The catalyst exhibits favorable activity with a low overpotential of 363 mV at a current density of 10 mA cm −2 and a low Tafel slope of 139 mV dec −1 . Moreover, the sample also shows excellent stability that the current density retains without obvious attenuation. The superior performance of the catalyst is attributed to the synergistic effect and loose structure. Overall, our work offers a neoteric avenue to synthesize the transition metal nitrides and tune the performance of the catalyst of OER on the basis of the non-noble metal.

Developing efficient and inexpensive oxygen evolution reaction (OER) electrocatalysts is crucial to address the everincreasing energy crisis and environment pollution. In this work, bimetallic nickel-iron carbonate hydroxide arrays were strongly grown on a conductive carbon cloth (NiFeCH/CC) through a facile one-step hydrothermal method, which were used as oxygen evolution reaction (OER) electrocatalysts. Ni 0.8 Fe 0.2 CH/CC requires overpotential of just 246 mV at 10 mA cm À 2 , Tafel slope of 43 mV dec À 1 , and charge transfer resistance of 3.1 Ω for OER in 1 M KOH. The catalyst also shows excellent durability by a long-term operation for 10 h. A post-OER study of Ni 0.8 Fe 0.2 CH/CC reveals that the NiFeOOH species form on the surface during OER and the carbonate ions still intercalate between the cationic layers. Benefiting from a threedimensional structure and Fe doping strategy, the performance of Ni 0.8 Fe 0.2 CH/CC has been improved. This work provides an effective strategy to design efficient OER electrocatalysts in alkaline media.