Study On The Effect Of Zn-doped On Hydrolytic Hydrogen Production Performance Of Al-Ga-In-Sn Composites Hydrolysis

Since the consumption and depletion of fossil fuels, people really urgent to find new energy sources to replace traditional fossil fuels. And hydrogen as a high-calorie, non-polluting new energy is noticed by scientists. However, the safety issues of hydrogen storage and transport are limited its further application. To solve these problems, we want to provide an online on-demand hydrogen supply system, to combine the hydrogen storage, transportation with production and achieve when we need to use we produce. So we can solve the problem of security issues in the hydrogen transport and storage procedures. Using solid hydrogen storage materials can solve the above problems and achieve online generation and application. And compared with conventional methods of transportation and storage, using solid hydrogen storage materials is more conducive to the transport hydrogen.Al alloy with its excellent performance stand out in the solid hydrogen storage materials. Al is abundant in the earth’s crust, and it is easy to obtain. What’s more, Al has low density, therefore it has a high energy density. Al is a kind of active metal, in theory, it can be directly reacted with water and produce hydrogen. However, when it is exposed in the air, it will be soon oxidized by oxygen, so the surface of Al forms a dense oxide film that prevents Al reaction with water further. Therefore, how to remove the surface oxide film of Al and make the Al react with water continued to produce hydrogen gas is the focus of scientist’s research.In this paper, using a simple method of melting and pouring, by adding Ga, In, Sn, Zn and other metal to activate Al, which format Al-Ga-In-Sn-Zn alloy, so that Al can be directly reacted with water. Generally, Al-Ga-In-Sn alloy can be directly reacted with water to produce hydrogen, but both Ga and In are rare and expensive. By doping Zn into the Al-Ga-In-Sn alloy can reduce the amount of Ga and In and reduce the production cost of the alloy under the premise of guaranteeing the hydrogen generation performance（including the yield of hydrogen generation and hydrogen generation rate）. In addition, by using XRD, SEM, EDX and DTA to analysis different proportions of alloy samples, and according to the results of the analysis, we suppose the mechanism of Zn-doped to the Al-Ga-In-Sn alloy.In the Al-Ga-In-Sn-Zn alloy, In and Sn can form two mainly different compounds In₃ Sn and In Sn₄. And Al-Ga-In Sn₄ alloy has less usage amount of metal In and lower cost, but the hydrogen generation performance is not ideal. The Zn doping corresponds to the Al-Ga-In₃Sn-Zn and Al-Ga-In Sn₄-Zn alloy, and there hydrogen generation performance has a significant change. For Al-Ga-In₃ Sn alloy, in the hydrogen generation performance, Zn doping makes the hydrogen yield of Al-Ga-In₃ Sn alloys decreased slightly, but the hydrogen generation rate greatly improved. And when the amount of Zn doping is 5%, integrated hydrogen generation performance is optimum. For Al-Ga-In Sn₄ alloy, in the hydrogen generation performance, Zn doping will reduce hydrogen generation rate of Al-Ga-In Sn₄ alloy significantly. But due to hydrogen generation rate of pure Al-Ga-In Sn₄ alloy is too fast, so the Zn doping can stabilize rates. In the hydrogen generation, Zn doping will improve the hydrogen yield of Al-Ga-In Sn₄ alloy significantly. When the amount of Zn doping is 10%, integrated hydrogen generation performance is best. In discussing the impact of Al-Ga-In₃Sn-In Sn₄ of Zn-doped, we found that when the ratio of In₃ Sn to In Sn₄ approaching single In₃ Sn or In Sn₄,the hydrogen generation performance is best. However when the proportion of In₃ Sn to In Sn₄ is 1: 1, the material has a poor hydrogen generation performance, which matches with the results of SEM and EDX. By observing the microstructure of Al-Ga-In₃Sn-In Sn₄-Zn, it can be found that single substance of Zn in the alloy. But when the proportion of In₃ Sn and In Sn₄ is 1: 1, there is less single substance of Zn, which may result in a decline in performance of its hydrogen generation. Therefore, we chose the proportion of In₃ Sn and In Sn₄ is 1: 3 as the optimal one. By a lot of experiments, we found that when the doping amount of Zn is 6%, the content In Sn compound 9%, we can get the best performance of hydrogen generation performance. Further, when the content of Zn changes from less to more, the In Sn particle is transition from the granular and spherical particles to the irregular flakes. What’s more, when fix the proportion of In₃ Sn and In Sn₄ is 1: 3 and change the amount of Zn and Ga, the amount of Zn doping is 9% and the amount of doping Ga is 6%, has a better hydrogen generation performance. And when the amount of Zn doping is less, In Sn particles tend to be spherical; when the amount of Zn doping more, In Sn particles tend to flake.Al-Ga-In-Sn-Zn alloy can react with water to produce hydrogen directly, and can reduce the manufacturing cost of the alloy under the premise of guaranteeing the hydrogen generation performance. Thereby it can solve the problem of hydrogen on the storage and transport. In addition, Ga, In, Sn, Zn and other metals are not participated in the reaction, when the reaction is end, these metals can be recycled.