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For practical application of sodium borohydride (NaBH[Formula: see text] hydrolysis to generate hydrogen, metallic catalysts with low cost but excellent activity are highly desired. However, it remains a big challenge to further improve the activity of non-noble metal catalysts. In this work, photocatalysis technology was successfully introduced to enhance the catalyst activity for NaBH4 hydrolysis. By means of conventional impregnation-reduction method, CoB nanocatalyst was evenly deposited on graphitic carbon nitride surface, resulting in a Schottky-type photocatalyst (CoB/CN). As expected, hydrogen generation rate was greatly boosted owing to light irradiation. According to the results of capture experiments, photoexcited electron from g-C3N4 could enrich the electron density of CoB surface, which leads to the improvement of catalyst activity. Additionally, the light irradiation facilitates the remarkable decrease of apparent activation energy. Compared with some reported noble metal catalysts, the CoB/CN presents higher activity, especially under light irradiation.

In this paper, CoO[Formula: see text]Co2P composite nanocatalysts as highly active catalysts were successfully prepared for catalytic hydrolysis of sodium borohydride (NaBH[Formula: see text] to generate hydrogen. For catalyst preparation, pre-synthesized Co(OH)2 nanosheets were uniformly mixed with sodium hypophosphite (NaH2PO[Formula: see text] and then treated through vapor-phase phosphorization process. For characterization, field-emission scanning electron microscopy (FE-SEM), energy dispersive spectrometry (EDS), X-ray diffraction (XRD), N2 adsorption–desorption measurement and X-ray photoelectric spectroscopy (XPS) were carried out, and traditional water-displacement method was performed to measure the hydrogen generation rate (HGR). It was found that component and catalytic activity of the composites were greatly affected by the ratio of Co(OH)2 to NaH2PO2. When the ratio was 2:1, the obtained catalyst composed of CoO and Co2P presented the highest HGR up to 3.94[Formula: see text]L min[Formula: see text] g[Formula: see text] using a 2[Formula: see text]wt.% NaBH[Formula: see text][Formula: see text]wt.% NaOH solution at [Formula: see text]C, and the apparent activation energy was detected as low as 27.4[Formula: see text]kJ mol[Formula: see text]. Additionally, the optimum CoO[Formula: see text]Co2P catalyst still retains 60% of the initial activity after recycling four times.