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Ni2B nanoparticle distributed on ordered SBA-15 mesoporous silica was prepared in situ and its catalytic activity for NaBH4 hydrolysis was investigated in the presented paper. The problem of Ni2B aggregation is resolved and the catalytic activity of Ni2B is also improved due to the effect of SBA-15. The catalytic activity increases with Ni2B/SBA-15 weight ratio increased from 1:4 to 2:1 and the catalyst with Ni2B/SBA-15 weight ratio of 2:1 has high catalytic activity close to that of Ni2B. The sintered experiment shows that the catalytic activity comes from amorphous Ni2B, not crystalline Ni2B. High sintering temperature leads to the conversion from amorphous Ni2B to crystalline Ni2B and damages the nanostructure of amorphous Ni2B framework.

The Al-Li-Ni3Sn2 composites were prepared via milling method and their hydrolysis performance was presented in the paper. The milled Al-Li-Ni3Sn2 composites showed high hydrolysis performance at 30-600C, especially that Al-3.5wt%Li-20wt%Ni3Sn2 composite had 100% and 1103 ml hydrogen/g of hydrogen yield within 20 min at 500C.The hydrolysis performance improvement of Al-Li-Ni3Sn2 composite was due to the addition of Ni3Sn2 while Ni3Sn2 combined with Al and formed nano structure of Ni-based alloys deposited on the surface of Al. The structure of Al-(Ni alloy) could act as active sites in the hydrolysis process because the milled products such as AlNi, Al-NiSn and Al- Ni3Sn2 had high electrochemical activity in the hydrolysis process. Therefore, Al-Li-Ni3Sn2 composites were a potential hydrogen source for fuel cell.

The formation of Bi-Li alloy and its potential mechanism to improve the hydrolysis kinetics of Al had been presented in the paper. Bi-Li alloy could exist steadily and deposited on Al surface uniformly from XRD and SEM-EDX results because Bi-Li alloy had low melting temperature. The formation of Al- BiLi3 microstructure created active sites which produced galvanic micro cell of Al and Bi in the hydrolysis process. Therefore, hydrolysis performance of Al- BiLi3 composites was significantly improved with BiLi3 content increasing.

The catalytic properties of oxidized Ni3Sn2 powders were investigated for producing hydrogen from decomposing methanol in the temperatures ranging from 240 to 480 ºC. The oxidized Ni3Sn2 had much higher catalytic activity than that of Ni3Sn2 in the temperature range of 320~400 ºC. The results of an isothermal test performed at 320 ºC revealed that the oxidized Ni3Sn2 was spontaneously activated within 4 h of the reaction and slowly deactivated in the followed reaction time. The oxidized Ni3Sn2 suppressed side reactions such as methanation and water-gas shift reaction and showed a high efficiency for H2 production from methanol decomposition. Surface analysis revealed that the activity of oxidized Ni3Sn2 was attributed to the formation of Ni/SnO2 catalyst, which was supposed to serve as active sites for methanol decomposition.

LiBH4 has high hydrogen storage capacity, and its high gravimetric hydrogen density reaches 18.36%. However, LiBH4 exhibits poor hydrolysis performance in water because the abrupt ending caused by the agglomeration of its hydrolysis products limits its full utilization [1, 2]. In this paper, four kinds of organics, namely, ethanol, tetrahydrofuran, acetic acid, and butanol (referred to MOH) were added to water, and the effect of MOH species and amount on the hydrolysis performances of LiBH4 was evaluated. Results show that agglomeration can be avoided and that LiBH4 has a controllable hydrogen generation rate and high hydrogen generation amount inMOH/water solutions compared with that in pure water. The order in terms of the hydrolysis performance of LiBH4 in MOH/water solutions is as follows: acetic acid >butanol> tetrahydrofuran >ethanol. From XRD, SEM, and other analyses, the enhancement performance is explained by the diluting and solvent effects. Moreover, the addition of MOH alters the hydrolysis route of LiBH4. MOH acts as not only a carrier for water and LiBH4 but also as a reactant to form intermediate LiBH4·[MOH(H2O)x]y, which slows the hydrolysis kinetics of LiBH4. Hydrolysis conditions were optimized, and high hydrogen amount was achieved correspondingly. The experimental data presents the potential application of LiBH4 as a highly efficiency and stable hydrogen source for fuel cells.

Hydrolysis of Al and NaBH4 for hydrogen generation has obtained considerable attention as a portable hydrogen source system. In this paper, we report a new combined hydrogen generation from Al powder and alkaline NaBH4 solution activated by NiCl2 additive. The system is characterized as the followed features: the interaction of Al/NaBH4 hydrolysis, catalytic effect of Ni2B for Al and NaBH4, Al hydrolysis stimulated by NaOH solution. The effects which affect the hydrogen generation performance of the system were studied. The results showed that a favorable combination of high hydrogen yield and high hydrogen generation rate might be obtained via the optimized composition design. Therefore, the system may be developed as a portable hydrogen source system.