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Sustainable electrocatalytic hydrogen production is a vital method for producing clean energy. However, the current platinum catalysts are costly and complicated to prepare with low catalytic activity. To obtain efficient catalysts, a facile method with a rational electrode design is essential to improve platinum activity and stability, facilitating the hydrogen evolution reaction (HER). Herein, we fabricated a self-supported HER composite electrode with abundant platinum activity sites by a simple metal–organic chemical vapor deposition, and nanostructured pine-like platinum was supported on carbon cloth (Pt/CC). Benefiting from the nanostructured pine-like platinum geometry, fast charge transfer, and good structure stability, this Pt/CC composite electrode exhibited excellent HER electrocatalytic activity. For HER, this electrode achieved a low overpotential of only 17.6 mV at 10 mA cm–2 in 1 M KOH. Moreover, Pt/CC exhibits long-term electrochemical durability, maintaining its catalytic activity for more than 30 h. What is more, this strategy can also be used on other self-supported substrates, e.g., nickel foam, to achieve high electrocatalytic activity. Thus, this work provides a simple and versatile method for the preparation of efficient HER catalysts. [ABSTRACT FROM AUTHOR]

A parallel Cu paddle wheel structure was developed to form an efficient C3H6 nano-trap. Benefiting from having this trap, ATC-Cu showed a very high capacity for binding C3H6 and high C3H6/C3H8 selectivity at 298 K. [ABSTRACT FROM AUTHOR]

Transition metal chalcogenides (TMCs) have been widely explored and utilized in sodium-ion battery (SIB) anodes owing to their unique advantages, such as high theoretical specific capacity and low cost. However, their inherent defects, such as low electronic conductivity and severe volume expansion, seriously limit the further development of TMC-based anodes. Here, a novel composite material of CoSe2 nanoparticles (NPs) encapsulated in a dual one-dimensional (1D) carbon composite structure (CoSe2@CNTs/N-CNFs) was designed deliberately. Carbon nanotubes (CNTs) were grown in situ on the surface of carbon nanofibers (CNFs) with eco-friendly ethanol as the carbon source, while electrospun polyacrylonitrile (PAN) fibers were pyrolyzed to form nitrogen-doped nanofibers. It is noted that the wrapping with the composite carbon structure greatly improved the stability of CoSe2 NPs and solved its inherent defects as an anode material. When assembled into a half-cell, the CoSe2@CNTs/N-CNFs electrode exhibited outstanding sodium storage performance with a reversible specific capacity of 442 mA h g−1 after 100 cycles at 0.1 A g−1, as well as excellent rate performance, and the discharge specific capacity still reached 265 mA h g−1 even after 2000 cycles at a high current density of 5 A g−1. This study shows a new way to build a novel carbon substrate and TMC composite sodium storage material with low cost. [ABSTRACT FROM AUTHOR]

The hydrogen evolution reaction (HER) has an important role in H2 production. Two-dimensional metal–organic framework nanosheets (2D MOF NSs) have become durable and efficient electrocatalysts for the HER due to their ultrathin thickness and large surface area, but such nanosheets are usually less conductive and tend to aggregate, which greatly affect their electrocatalytic efficiency. The introduction of carbon nanotubes (CNTs) on the substrate nanosheets may prevent the aggregation of nanosheets, enhance their conductivity and bring the synergistic effect of multilevel nanostructures. Herein, we propose a simple and unique strategy to yield electrocatalysts with multilevel nanostructures, in which CNTs are grown in situ from 2D Ni-MOF NSs through calcination. Ni nanoparticles (NPs) encapsulated at the tips of CNTs can be readily converted into NiSe2 NPs after selenization. The optimized NiSe2-NPs/CNTs/Ni-MOF NS catalyst exhibits an enhanced electrocatalytic HER performance. Furthermore, the two-electrode system that uses NiSe2-NPs/CNTs/Ni-MOF NSs/NF as both the anode and the cathode shows good electrocatalytic activity toward overall water splitting in 1.0 M KOH. This report provides a new insight into the synthesis of CNTs from simple MOFs and multilevel nanostructures composed of metal chalcogenide NPs, CNTs and 2D Ni-MOFs for efficient electrocatalytic HER. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks possessing relatively large pores, high surface areas, and unsaturated metal sites are attractive materials for use as electrocatalysts in the reduction of N2 to NH3. In this work, a MIL-101(Fe)/MoS3 hybrid catalyst, prepared by using a precursor-transformation strategy, is shown to be an effective electrocatalyst for the N2 reduction reaction (NRR). Under solvothermal conditions, micro-sized octahedral MIL-101(Fe) precursors are converted into ultra-small nanodots, while amorphous MoS3 derived from (NH4)2MoS4 provides a surface suitable for anchoring the MIL-101(Fe) nanodots. The as-prepared composite exhibits excellent electrocatalytic activity and durability for the NRR with a Faraday efficiency of 36.71% and an NH3 yield of 25.7 µg h−1 mgcat−1 at −0.1 V vs. RHE in 0.1 M HCl. The results show that the dispersion and adherence of MIL-101(Fe) nanodots on amorphous MoS3 improves the exposure of active centers and aids mass transfer, resulting in greatly enhanced catalytic activity and stability. [ABSTRACT FROM AUTHOR]