Tungsten-Doped Molybdenum Sulfide with Dominant Double-Layer Structure on Mixed MgAl Oxide for Higher Alcohol Synthesis in CO Hydrogenation

Improving the C₂+ alcohols selectivity is highly desirable for higher alcohols synthesis in CO hydrogenation. Herein, an effective method was developed for Mo-based supported catalysts by the combination of tungsten-doping and surfactant-assisted hydrothermal strategy. The tungsten-doping enhanced the interaction between Ni and W/Mo metal species to form more of the Ni-MoW-S phase with tunable slab size and stacking layers, and thus promoted the chain growth of alcohol to form a greater amount of higher alcohols in CO hydrogenation. The optimal K,Ni–Mo_0.75W_0.25/MMO-S exhibited a dominant double-layer structure (∼39.0%) and highly synergetic effects between Ni and W/Mo species, resulting in the highest total alcohol selectivity (76.1%) and in higher alcohols selectivity. This work provides a new route for tuning the morphology of MoS₂/WS₂ and synergetic effects between Ni and W/Mo species in supported catalysts to improve the selectivity of higher alcohols

Molybdenum Polysulfide Anchored on Porous Zr-Metal Organic Framework To Enhance the Performance of Hydrogen Evolution Reaction

Replacement of precious platinum with efficient and low-cost catalysts for electrocatalytic hydrogen evolution reaction (HER) at low overpotentials holds tremendous promise for clean energy devices. Herein, molybdenum polysulfide (MoS_<i>x</i>) anchored on a porous Zr-metal organic framework (Zr-MOF, UiO-66-NH₂) by chemical interactions is fabricated by a facile and one-pot solvothermal method for HER application. The distinctive design of the Zr-MOF stabilized MoS_<i>x</i> composite enables remarkable electrochemical HER activity with a Tafel slope of 59 mV·dec^–1, a lower onset potential of nearly 125 mV, and a cathode current of 10 mA·cm^–2 at an overpotential of 200 mV, which also exhibits excellent durability in an acid medium. The superior HER performance should ascribe to the fast electron transport from the less conducting MoS_<i>x</i> nanosheets to the electrode, high effective surface area, and number of active sites, as well as the favorable delivery for local protons in the porous Zr-MOF structure during the electrocatalytic reaction. Thus, this work paves a potential pathway for designing efficient Mo-based HER electrocatalysts by the combination of molybdenum polysulfide and versatile proton-conductive MOFs

Strongly Coupled FeNi Alloys/NiFe₂O₄@Carbonitride Layers-Assembled Microboxes for Enhanced Oxygen Evolution Reaction

Hydrogen produced from electrocatalytic water splitting is a promising route due to the sustainable powers derived from the solar and wind energy. However, the sluggish kinetics at the anode for water splitting makes the highly effective and inexpensive electrocatalysts desirable in oxygen evolution reaction (OER) by structure and composition modulations. Metal–organic frameworks (MOFs) have been intensively used as the templates/precursors to synthesize complex hollow structures for various energy-related applications. Herein, an effective and facile template-engaged strategy originated from bimetal MOFs is developed to construct hollow microcubes assembled by interconnected nanopolyhedron, consisting of intimately dominant FeNi alloys coupled with a small NiFe₂O₄ oxide, which was confined within carbonitride outer shell (denoted as FeNi/NiFe₂O₄@NC) via one-step annealing treatment. The optimized FeNi/NiFe₂O₄@NC exhibits excellent electrocatalytic performances toward OER in alkaline media, showing 10 mA·cm^–2 at η = 316 mV, lower Tafel slope (60 mV·dec^–1), and excellent durability without decay after 5000 CV cycles, which also surpasses the IrO₂ catalyst and most of non-noble catalysts in the OER, demonstrating a great perspective. The superior OER performance is ascribed to the hollow interior for fast mass transport, in situ formed strong coupling between FeNi alloys and NiFe₂O₄ for electron transfer, and the protection of carbonitride layers for long stability