A Metal–Organic Frameworks Derived 1T‐MoS₂ with Expanded Layer Spacing for Enhanced Electrocatalytic Hydrogen Evolution

Abstract

Metal phase molybdenum disulfide (1T‐MoS2) is considered a promising electrocatalyst for hydrogen evolution reaction (HER) due to its activated basal and superior electrical conductivity. Here, a one‐step solvothermal route is developed to prepare 1T‐MoS2 with expanded layer spacing through the derivatization of a Mo‐based organic framework (Mo‐MOFs). Benefiting from N,N‐dimethylformamide oxide as external stress, the interplanar spacing of (002) of the MoS2 catalyst is extended to 10.87 Å, which represents the largest one for the 1T‐MoS2 catalyst prepared by the bottom‐up approach. Theoretical calculations reveal that the expanded crystal planes alter the electronic structure of 1T‐MoS2, lower the adsorption–desorption potentials of protons, and thus, trigger efficient catalytic activity for HER. The optimal 1T‐MoS2 catalyst exhibits an overpotential of 98 mV at 10 mA cm−2 for HER, corresponding to a Tafel slope of 52 mV dec−1. This Mo‐MOFs‐derived strategy provides a potential way to design high‐performance catalysts by adjusting the layer spacing of 2D materials.

Large‐Scale, Controllable Synthesis of Ultrathin Platinum Diselenide Ribbons for Efficient Electrocatalytic Hydrogen Evolution

“…Applying the extrapolation method to the Tafel diagram, the exchange current density (j 0 ) of the PtSe 2 ribbon catalyst treated with plasma for 10 s was obtained, reaching 204 µA cm −2 , much higher than that of other common TMDC catalysts. [23] Figure 5g,h compare the HER performance, including the Tafel slope, η 10 and j 0, of monolayer PtSe 2 ribbons with that of other TMDC-based catalysts, [23][24] further showing the excellent performance of PtSe 2 ribbons.…”

Fabrication of Size-Controlled MOF-74-Derived Porous Nanospheres toward Efficient Water Treatment

“…PXRD pattern analysis shows that except for Mg−N− C900, there is a wide diffraction peak between 2θ = 20−30°, which corresponds to the (002) and (101) crystal planes of graphitized amorphous carbon, and there is a small peak at 2θ = 26°in Mg−N−C900, which corresponds to crystal carbon, which is the (002) crystal plane of graphene. 41 For lowtemperature calcination at 400 and 500 °C, the characteristic peaks of MOF-74 exist at 2θ = 7°and 12°, 34 indicating that the original crystallinity of the structure is maintained at these temperatures, but partial carbonization occurs. When calcined above 600 °C, the diffraction peak of a small angle gradually disappears, and the MOF-74 skeleton collapses, corresponding to (200), ( 220), (311), and (222) crystal planes of MgO at 2θ = 42.9°, 62.3°, 74.6°, and 78.5°, respectively.…”

Unveiling the capacitive energy storage of linear CTAB or tetrahedral TBAB organic-molecule intercalated MoS2

“…MoS 2 shows multiple phases in different polymorphs, and the 2H phase (a semiconducting hexagonal phase with a trigonal prismatic crystal structure, 2H-MoS 2 ) and 1T phase (a metallic phase with a triclinic crystal structure and edge-sharing octahedra, 1T-MoS 2 ) are the two typical crystal structures. [19][20][21][22] The metallic 1T-MoS 2 should be more favorable as an electrode for supercapacitors because it is not only more conductive which is benecial for electron transport, but also has a larger interlayer space that would facilitate the intercalation of metal cations in the electrolyte. 15,23,24 But, 1T-MoS 2 is metastable from a thermodynamic viewpoint.…”