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Exploiting low-cost electrocatalysts with highly efficient and stable catalytic activity in both acidic and alkaline solutions is the key to the large-scale application of hydrogen production by water electrolysis. Here, Ru nanoparticle-anchored MoP@Mo composites were synthesized by high-temperature phosphorization combined with the photodeposition method. Ru/MoP@Mo as an electrocatalyst for the hydrogen evolution reaction exhibited a Pt-like electrocatalytic activity, including low overpotentials of 54 and 52 mV at a 10 mA·cm–2 current density in 0.5 M H2SO4 and 1.0 M KOH solutions, respectively, small Tafel slopes, and long-term stability at a current density of 10 mA·cm–2. Meanwhile, theoretical calculations revealed that the excellent catalytic activity of Ru/MoP@Mo was ascribed to the strong electronic interaction between Ru and MoP, which optimizes the adsorption tension of H on the surface and thereby accelerates the adsorption and desorption of H. This work provides a new strategy for preparing Mo-based HER electrocatalysts with high catalytic activity in both acidic and alkaline environments. [ABSTRACT FROM AUTHOR]

MoSe2 as one graphene-like 2D transition metal selenide has attracted great attention. However, its application for the hydrogen evolution reaction (HER) is still restricted by the poor electrical conductivity and structural restacking. In this work, an excellent electrocatalyst for hydrogen production is developed based on the in situ synthesis of V-doped MoSe2 confined on carbon black nanoparticles (denoted as V-MoSe2/CB) via a sol–gel process. The characterization results show that the carbon black nanoparticles can protect the V-MoSe2 nanosheets from agglomeration, resulting in ultra-thin thickness and short vertical lattice arrays. Meanwhile, density functional theory (DFT) calculations indicate that vanadium doping can optimize the electronic structure of MoSe2. Accordingly, compared to the pure MoSe2, V-MoSe2 and MoSe2/CB electrocatalysts, V-MoSe2/CB exhibits improved electrocatalytic activity with a small overpotential of 166 mV at −10 mA cm−2 and a small Tafel slope of 65 mV dec−1. This work paves a new way for improving the HER performance through synergistic morphology, structure and electronic regulation. [ABSTRACT FROM AUTHOR]

In this work, we developed an evaporation crystallization method combined with a hydrogen thermal reduction method to construct a MoO2/MoS2 heterojunction on carbon nanotubes (denoted as MoO2/MoS2@CNT) for hydrogen evolution. In the HER process, the resultant MoO2/MoS2@CNT exhibited excellent catalytic activity, which featured a small overpotential of 158 mV at a current density of 10 mA cm−2 along with a Tafel slope of 70 mV dec−1 as well as excellent stability in 0.5 M H2SO4. Experimental findings and theoretical calculations show that the excellent electrocatalytic performance is mainly due to the strong interaction between MoO2 and MoS2, which can help to effectively optimize the electronic structure, lower the catalytic energy barrier, and thereby enhance the HER activity. This work provides an effective strategy for constructing a heterojunction to regulate the electron structure, which will generate more inspiration for designing efficient electrocatalysts. [ABSTRACT FROM AUTHOR]

Exploration of highly efficient and stable electrocatalysts for hydrogen production is critically important for their practical applications in water splitting. Herein, we present Ru nanoparticle-anchored MoO2 nanoflowers as an efficient and stable electrocatalyst for hydrogen evolution reaction (HER). The Ru/MoO2 catalysts are synthesized by a mild hydrothermal route combined with thermal reduction. The strong electronic interactions between Ru and MoO2 confirmed by density functional theory (DFT) calculations lead to better hydrogen adsorption abilities and produce many more active sites. As a result, the optimized Ru/MoO2 hybrid delivers outstanding HER performance in an acid solution, with a low overpotential of 39 mV to reach an electric current density of 10 mA/cm2, a small Tafel slope of 50 mV/dec, and superior long-term stability. The work presents a good strategy to develop efficient and stable HER catalysts by introducing strong electronic interactions. [ABSTRACT FROM AUTHOR]