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Benefiting from the high electrochemical surface area brought by the 2D nanosheet structure, MoS2 has received great research attention for the hydrogen evolution reaction (HER). Recently, it has been demonstrated that by constructing a transitional metal sulfide–MoS2 heterostructure, the HER performance of the MoS2-based catalysts can be further improved. It is even possible to obtain bifunctional catalysts for both HER and oxygen evolution reaction (OER) due to the synergistic effect of the different components in the composite, the electronic effect to enable an efficient electron transfer and appropriate binding energy for the intermediates of the electrocatalytic reactions, and the surface defects on the interface of the heterostructures. Herein, we review the recent progress on the construction of the transitional metal sulfide–MoS2 heterostructure for water splitting based on non-self-supporting and self-supporting catalysts. The surface and interface parameters of the heterostructures are discussed in detail to reveal the key roles of the hybrid structures for energy conversion. We also pay special attention to the theoretical simulations based on first principles to clarify the relationships between the electrochemical performance and structure parameters. Finally, the prospects and challenges of the transition metal sulfide–MoS2 heterostructures for water splitting in the future are proposed to prompt the reasonable design of transition metal sulfide–MoS2 heterostructures for full water splitting. [ABSTRACT FROM AUTHOR]

Boron-containing cobalt (Co–B) nanoparticles (NPs) synthesized by the borohydride reduction process were subjected to ammonization. Part of B species segregate onto particle surfaces to form ultrathin h-BN shells which stabilize highly dispersed Co NPs under harsh conditions and the remaining B atoms interact strongly with Co atoms inside the NPs. The formed CoBx@h-BN core–shell nanocatalysts exhibit an overpotential of 290 mV at a current density of 10 mA cm−2 making them among the most active catalysts for the oxygen evolution reaction (OER) and they present 150 h OER stability. The improved OER performance has been attributed to the synergetic role of the confinement effect of h-BN shells and activation effect of subsurface B atoms. This work suggests a simple synthetic route to prepare highly active and stable metal nanocatalysts without using any surfactants and supports. [ABSTRACT FROM AUTHOR]

CO2 capture via solid adsorption technology relies on the development of low-cost and high-performance new solid adsorbents. The robust and large-scale produced hexagonal boron nitride (h-BN) porous materials are an ideal candidate but present low CO2 adsorption properties. Here, we report that in situ carbon doping of BN materials (BCN) can be facilely controlled by thermal annealing of boric acid and melamine mixtures in various atmospheres. CO2 uptake of the BCN materials is in the range of 3.74–3.91 mmol CO2 g−1 (165–172 mg CO2 g−1) at 298 K and ambient pressure, whereas it is only 1.16–1.66 mmol CO2 g−1 (53.0–73.1 mg CO2 g−1) over the pure BN materials. The separation coefficient between CO2 and N2 is up to 74 and no decrease in the adsorption performance was observed after nine adsorption/desorption cycles. The BCN material presents the best performance among known BN-based sorbents, which is comparable to many excellent carbon materials. Detailed characterization reveals that the incorporation of carbon into the BN matrix increases the density of ultramicropores (＜0.7 nm) and chemical defects, consequently enhancing the CO2 adsorption capacity and the selectivity over N2 molecules. [ABSTRACT FROM AUTHOR]