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Rapid chemical transformation from micelle templated precursors (metal nitrate and citric acid) to ordered mesoporous metal carbonates and oxides is demonstrated using microwave heating for cobalt, copper, manganese and zinc. Without aging requirements, <3 min of microwave processing yields highly ordered mesoporous films.

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Transition metal oxides (TMOs) have acquired much attention on account of their abundant reserves and variable components, but sluggish charge transfer rate, limited electrochemically active sites, and poor conductivity hamper their extensive applications in the hydrogen evolution reaction (HER). Herein, we have synthesized nitrogen-doped CoMoO 4 clusters constituted of nanosheets directly supported on nickel foam (N-CoMoO 4 /NF) by combining a hydrothermal process and lowtemperature ammonia annealing treatment. Experimental results reveal that the nitrogen doping can modulate the electronic structure of CoMoO 4 , in which Mo ions with +6 valence are reduced to a lower state, and thus enhance its catalytic performance for HER. The optimized N-CoMoO 4 /NF (N-CoMoO 4 /NF-1, with the annealing time of 1 h in NH 3 atmosphere) exhibits excellent activity toward alkaline HER, requiring an overpotential of 58 mV at 10 mA/cm 2 . This work possesses great potential for promoting alkaline HER performance of TMOs by the facile process of nitrogen doping.

The synthesis of ultrafine and well‐distributed rhodium nanoparticles (NPs) with high efficiency toward methanolysis of ammonia borane (AB) is crucially important but challenging. A facile approach has been developed for synthesizing ultrafine and uniform Rh NPs deposited on carbon by using the small soluble organic molecule (SOM) of l‐proline (PRO) as capping agent (Rh‐PRO/C). The enrichment of N,O‐coordination sites for the metal precursor by using PRO was found to be the key to the synthesis Rh‐PRO/C. The as‐prepared Rh‐PRO/C showed high catalytic activity for ammonia borane methanolysis with the highest total turnover frequency (TOF) of 1035 molnormalH2  (molRh min)−1 under basic conditions, which was three times higher than that of the state‐of‐the‐art Rh‐based catalysts. The excellent catalytic performance of Rh‐PRO/C was ascribed to the well‐dispersed Rh NPs and the PRO‐functionalized metal surface, which can provide more active sites for the reaction. The merit of size‐controlled synthesis combined with metal NP surface modification by SOMs is likely to be beneficial in various catalytic fields.

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The development of cost‐effective electrocatalysts with high activity and sufficient stability for hydrogen evolution reaction (HER) is crucial for the widespread application of water electrolysis for sustainable H2 production. Transition metal oxides are desirable alternatives to replace benchmark Pt‐based HER electrocatalysts because of their cost effectiveness, facile synthesis, versatile compositions, and easy electronic structure tuning. However, most available transition metal oxides show poor performance for HER catalysis. Here, it is reported that the anatase TiO2 can be efficiently developed into a superior HER electrocatalyst with comparable activity to Pt‐based electrocatalysts in alkaline solution through simultaneous morphology control, proper lattice doping, and surface active sites engineering. Specifically, the obtained cobalt‐doped TiO2 nanorod arrays (Co‐TiO2@Ti(H2)) show a low overpotential of only 78 mV at 10 mA cm−2, a small Tafel plot of 67.8 mV dec−1, and excellent stability even at an ultralarge current density of ≈480 mA cm−2 in 1.0 m KOH solution. Theoretical calculations demonstrate that the introduction of Co with rich oxygen vacancies can efficiently lower the energy barrier for water adsorption/dissociation and H intermediate desorption. This work uncovers the potential of the low‐cost transition metal oxides as alternative HER electrocatalysts in alkaline water electrolysis.