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The chemical storage of hydrogen is well accomplished by ammonia borane. However, a significant barrier to utilizing ammonia borane practically is developing extraordinarily effective and inexpensive catalysts that propel hydrogen evolution from it. In this work, the catalyst Pt@Ni2P/nickel foam (NF) is synthesized by embedding platinum (Pt) nanoparticles over self-supported Ni2P/NF. Pt@Ni2P/NF enables a high synergetic effect between Pt nanoparticles and Ni2P/NF, boosting the hydrolysis of ammonia borane. The catalyst Pt@Ni2P/NF activity enriches 3.0-fold compared to Ni2P/NF and 25.5-fold compared to pristine Ni2P. X-ray photoelectron spectroscope analysis reveals that embedding Pt nanoparticles over self-supported Ni2P generates a strong interaction between (Ni2P/NF)δ+and (Pt)δ−. The chemical kinetic results reveal that the activation energy and turnover frequency of Pt@Ni2P/NF are calculated to be 31.0 kJ mol–1and 63.2 min–1for 0.13 M AB. This study demonstrates a reliable method used to develop active sites of (Ni2P)δ+and (Pt)δ−for ammonia-borane hydrolysis. The controllable hydrogen release and facile on/off characteristic of the catalyst demonstrate a feasible way to boost the catalytic performance by constructing a two-dimensional (2D) structure.

Catalytic hydrolysis of ammonia borane has drawn much attention for on-board hydrogen generation because of its high hydrogen capacity. Herein, a ternary Au-WO2.72/TiO2hybrid is synthesized for efficient photohydrolysis of ammonia borane. The Au nanoparticles (NPs) deposited were in situ-reduced by defective WO2.72nanowires, and 2 wt % Au-WO2.72is optimal to realize high photoactivity because of the high light absorption and low charge-transfer resistance, which is then combined with TiO2nanosheets to form a 2%Au-WO2.72/TiO2hybrid. This hybrid possesses compact interfaces among Au, WO2.72, and TiO2, and the electron pump effect of Au surface plasmon resonances and the electron capture property of TiO2accelerate the electron transfer from WO2.72to Au and then to TiO2, leading to the effective separation and long lifetime of photoinduced charges. Therefore, the 2%Au-WO2.72/TiO2hybrid shows very high catalytic activity under visible light with H2evolution rates 2.67- and 31-times higher than those for 2%Au-WO2.72and WO2.72, respectively.

Two collections of inbred lines were divided into early (E), medium (M) and late (L) germinating lines, on the basis of days to germination under growth-cabinet conditions at 8°C and 6°C constant temperatures. Tolerance of low temperatures was found to be an heritable trait and characteristic of each inbred line.