A proof-of-concept strategy for significant enhancement of hydrogen evolution reaction (HER) performance of transition metals via construction of a metal/semiconductor Schottky junction is presented. The decoration of low-cost commercial TiO2 nanoparticles on the surface of microscale Co dendrites causes a significant charge transfer across the Co/TiO2 Schottky interface and enhances the local electron density at the Co surface, confirmed by X-ray photoelectron spectroscopy results and density functional theory calculations. The Co/TiO2 Schottky catalyst displays superior HER activity with a turnover frequency of 0.052 s–1 and an exchange current density of 79 μA cm–2, which are about 4.3 and 4.0 times greater than that of pristine Co, respectively. Moreover, the Co/TiO2 Schottky catalyst displays excellent electrochemical durability for long-term operation in both alkaline solution and high saline solution. Theoretical calculations suggest that the Schottky junction plays an important role to optimize hydrogen adsorption free energy (ΔG H*) by tuning the electronic structure, which enhances the performance for HER of the Co/TiO2 Schottky catalyst. This study of modulating the electronic structure of the catalysts via the Schottky junction could provide valuable insights for designing and synthesizing low-cost, high-performance electrocatalysts.

Alloying platinum (Pt) with transition metals (M), as an established class of electrocatalysts, reduces the use of Pt and improves the electrocatalytic performance. However, the stability of transition metals in nanostructured platinum alloys is a fundamental and practical problem in electrocatalysis, due to leaching of transition metals under acidic operating condition. Here, a corrosion method has been developed for a PtÀ Cu electrocatalyst with high activity (6.6 times that of commercial Pt/C) and excellent stability for the methanol oxidation reaction (MOR) under acidic operating conditions. The mechanism of formation has been studied, and possible mesostructured re-formation and atomic re-organization have been proposed. This work offers an effective strategy for the facile synthesis of a highly acid-stable PtM alloying and opens a door to high-performance design for electrocatalysts.

The development of a highly efficient and secure system for hydrogen storage and delivery is currently imperative, yet has great challenges. Herein, a series of highly dispersed and small cobalt nanoparticles supported by MOF-derived hierarchically porous carbon were synthesized by employing a selective atom evaporated-isolation strategy with bimetal Co/Zn-MOF-74 used as sacrificial template. The formation of ultrasmall Co nanoparticles in the hierarchically porous carbon was largely due to the assistance of doped Zn atoms in Co/Zn-MOF-74 precursors, which restricted their agglomeration during pyrolysis. Detailed catalytic results indicated that both the mole ratio of Co/Zn and the pyrolysis temperature were crucial to modulate their dehydrogenation performance for ammonia–borane, of which the as-synthesized 30% Co/HPC catalyst pyrolyzed under 900 °C exhibited the highest catalytic activity. Furthermore, these Co/HPC catalysts also showed good structure stability and magnetically reusability, which, together with the superior activity, enabled them to hold great promise for practical applications.

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Hierarchically fractal Co with highly exposed active (002) facets, possessing higher work function and more moderate hygrogen adsorption free energy, has been synthesized via template-free self-assembly method for directed electron-transfer...