Development of efficient and robust electrocatalysts is critical for practical fuel cells. We report one-dimensional bunched platinum-nickel (Pt-Ni) alloy nanocages with a Pt-skin structure for the oxygen reduction reaction that display high mass activity (3.52 amperes per milligram platinum) and specific activity (5.16 milliamperes per square centimeter platinum), or nearly 17 and 14 times higher as compared with a commercial platinum on carbon (Pt/C) catalyst. The catalyst exhibits high stability with negligible activity decay after 50,000 cycles. Both the experimental results and theoretical calculations reveal the existence of fewer strongly bonded platinum-oxygen (Pt-O) sites induced by the strain and ligand effects. Moreover, the fuel cell assembled by this catalyst delivers a current density of 1.5 amperes per square centimeter at 0.6 volts and can operate steadily for at least 180 hours.

Production of hydrogen by electrochemical water splitting has been hindered by the high cost of precious metal catalysts, such as Pt, for the hydrogen evolution reaction (HER). In this work, novel hierarchical β-Mo2 C nanotubes constructed from porous nanosheets have been fabricated and investigated as a high-performance and low-cost electrocatalyst for HER. An unusual template-engaged strategy has been utilized to controllably synthesize Mo-polydopamine nanotubes, which are further converted into hierarchical β-Mo2 C nanotubes by direct carburization at high temperature. Benefitting from several structural advantages including ultrafine primary nanocrystallites, large exposed surface, fast charge transfer, and unique tubular structure, the as-prepared hierarchical β-Mo2 C nanotubes exhibit excellent electrocatalytic performance for HER with small overpotential in both acidic and basic conditions, as well as remarkable stability.

The design of cheap and efficient water splitting systems for sustainable hydrogen production has attracted increasing attention. A flexible electrode, based on carbon cloth substrate and iron phosphide nanotubes coated with an iron oxide/phosphate layer, is shown to catalyze overall water splitting. The as-prepared flexible electrode demonstrates remarkable electrocatalytic activity for both the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER) at modest overpotentials. The surface iron oxide/phosphate, which is formed in situ, is proposed to improve the HER activity by facilitating the water-dissociation step and serves directly as the catalytically-active component for the OER process.

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The surface reconstruction of cobalt phosphide nanosheets is investigated by an in situ electrochemical strategy for enhanced hydrogen evolution.

Production of hydrogen by electrochemical water splitting has been hindered by the high cost of precious metal catalysts,s uch as Pt, for the hydrogen evolution reaction (HER). In this work, novel hierarchical b-Mo 2 Cn anotubes constructed from porous nanosheets have been fabricated and investigated as ahigh-performance and low-cost electrocatalyst for HER. An unusual template-engaged strategy has been utilized to controllably synthesize Mo-polydopamine nanotubes,w hich are further converted into hierarchical b-Mo 2 C nanotubes by direct carburization at high temperature.B enefitting from several structural advantages including ultrafine primary nanocrystallites,l arge exposed surface,f ast charge transfer,a nd unique tubular structure,t he as-prepared hierarchical b-Mo 2 Cn anotubes exhibit excellent electrocatalytic performance for HER with small overpotential in both acidic and basic conditions,aswell as remarkable stability.

Developing robust electrocatalysts and advanced devices is important for electrochemical carbon dioxide (CO2) reduction toward the generation of valuable chemicals. We present herein a carbon‐confined indium oxide electrocatalyst for stable and efficient CO2 reduction. The reductive corrosion of oxidative indium to the metallic state during electrolysis could be prevented by carbon protection, and the applied carbon layer also optimizes the reaction intermediate adsorption, which enables both high selectivity and activity for CO2 reduction. In a liquid‐phase flow cell, the formate selectivity exceeds 90 % in a wide potential window from −0.8 V to −1.3 V vs. RHE. The continuous production of ca. 0.12 M pure formic acid solution is further demonstrated at a current density of 30 mA cm−2 in a solid‐state electrolyte mediated reactor. This work provides significant concepts in the parallel development of electrocatalysts and devices for carbon‐neutral technologies.

A novel 3D hierarchical nanocomposite of vertically aligned porous FeP nano­wires on reduced graphene oxide is prepared as a demonstration of constructing an efficient hydrogen evolution catalyst. Extension of this nanostructuring strategy to other functional nanocomposites by combining different dimensional nanomaterials is attractive.