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Leveraging solar energy through photocatalytic hydrogen production from water stands out as one of the most promising approaches to address the energy and environmental challenges. The choice of catalyst profoundly influences the outcomes of photocatalytic reactions, and constructing heterojunctions has emerged as a widely applied strategy to overcome the limitations associated with single-phase photocatalysts. MoO3, renowned for its high chemical stability, encounters issues such as low photocatalytic efficiency and fast recombination of photogenerated electrons and holes. To tackle these challenges, the morphology of MoO3 has been controlled to form nanorods, simultaneously suppressing the aggregation of the catalyst and increasing the number of surface-active sites. Moreover, to facilitate the separation of photogenerated charge carriers, Cd0.9Zn0.1S nanoparticles with a twin crystal structure are deposited on the surface of MoO3, establishing an S-scheme heterojunction. Experimental findings demonstrate that the synergistic effects arising from the well-defined morphology and interface interactions extend the absorption range to visible light response, improve charge transfer activity, and prolong the lifetime of charge carriers. Consequently, Cd0.9Zn0.1S/MoO3 S-scheme heterojunctions exhibit outstanding photocatalytic hydrogen production performance (3909.79 μmol g−1 h−1) under visible light irradiation, surpassing that of MoO3 by nearly nine fold. [ABSTRACT FROM AUTHOR]

Iron molybdate (FeMoO 4) nanostructures show great promise as a superior anode for sodium-ion batteries. However, its use in practical application is hampered by its poor electronic conductivity, large volume changes and sluggish reaction kinetics. Herein, we have developed an interconnected network of multiwall carbon nanotube (CNT) and FeMoO 4 (FMO) by a simple one-step hydrothermal method. As well as providing efficient channels for charge transfer and diffusion, highly conductive CNTs also have a degree of volume elasticity and excellent electrical conductivity to ensure migration of sodium ions, enabling both fast kinetics and long-term stability. As a result, the FMO@CNT anode delivers a high reversible capacity of 485 mA h g−1 at 0.05 A/g and very long cycling stability with a capacity of 75 mA h g−1 after 1000 cycles at 1 A/g. Furthermore, by combining the ex-situ X-ray diffraction, ex situ X-ray photoelectron spectroscopy and cyclic voltammetry results, sodium ion storage mechanism of the FMO@CNT electrode obeys a conversion mechanism. The results of this work provide a better understanding on the sodium ion storage mechanism of binary metal oxides. [ABSTRACT FROM AUTHOR]

MoN is a promising material for electrochemical hydrogen evolution due to its cheap price and excellent catalytic activity sites, but the low conductivity prevents further improvement of its catalytic performance. In this work, porous MoN nanorods have been fabricated with an efficient and facile precursor method. XRD, Raman and TEM showed MoN nanorods with diameters of about 100 nm. With a simple mechanical mixing method, MoN/conductive carbon black (CB) composites with different weight ratios have been fabricated. The composite possessed two merits, that is, the more catalytic active site in MoN nanorods due to the porous structure, and fast electron transfer due to the CB. So, it has been used as a hydrogen evolution material. With the proper weight ratio, the composite exhibited brilliant catalytic activity and durability in acidic media. It possesses an overpotential of 162 mV to approach 10 mA cm, a small Tefel slope of 54 mV dec and maintains the good electrocatalytic activity for at least 10 h. Cyclic voltammetry and electrochemical impedance spectroscopy indicated that the electrocatalyst possessed a high catalytic active area and fast electron transfer. These results can compare with many other recently reported nitride catalysts. Our work possibly provides a new avenue for the preparation of a MoN-based catalyst for highly efficient electrochemical hydrogen evolution. [ABSTRACT FROM AUTHOR]

A phase-mixed MgTiO3–MgTi2O5 heterogeneous nanorod is fabricated via an ethylene glycol-mediated route to promote the photocatalytic hydrogen production activity significantly. The excellent charge separation and fast electron transport are the main reasons for the high efficiency due to the formation of phase-mixed heterogeneous junctions. [ABSTRACT FROM AUTHOR]