Jiaxing Xie , Min Liu , Zhendong Yao , Yongfu Cui , Wenqing Li , Meiqiang Fan
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引用次数: 0
Abstract
The hydrolysis of silicon and its compounds to produce hydrogen for fuel cell remains a major problem. In this work, the active metal calcium and lithium are introduced into the silicon system by preparing Li–Ca–Si ternary alloy. The preferential hydrolysis of active metal in the alloy led to the formation of weakly alkaline environment. It is proved that 25 % Li–CaSi2 alloy (25 Li) with a large number of secondary nano-phase has the highest electrochemical activity through electrochemical tests, the presence of the secondary nano-phase optimizes the reaction kinetics. Then the 25 Li shows the rapidest kinetics and highest yield in 0.5 M NaF solution, delivering a hydrogen yield of 590 mL g−1 in 20 min and maintain a long-term stable dehydrogenation. In addition, the system still reaches a retention rate of 89 % after exposing to air for 24 h. Furthermore, the above system achieves hydrogen-electric conversion in fuel cell tests. This work provides a novel idea for the research of Si-water system for hydrogen production, and provides a reference for the practical applications on fuel cells in the future.
水解硅及其化合物以产生用于燃料电池的氢气仍然是一个重大问题。在这项研究中,通过制备锂-钙-硅三元合金,将活性金属钙和锂引入硅体系。合金中活性金属的优先水解导致弱碱性环境的形成。通过电化学测试证明,含有大量次生纳米相的 25% Li-CaSi2 合金(25 Li)具有最高的电化学活性,次生纳米相的存在优化了反应动力学。在 0.5 M NaF 溶液中,25 Li 的反应动力学最快,产氢量最高,20 分钟内产氢量达到 590 mL g-1,并能保持长期稳定的脱氢反应。此外,上述系统在燃料电池测试中实现了氢电转换。这项工作为硅水制氢系统的研究提供了一个新思路,并为未来燃料电池的实际应用提供了参考。
期刊介绍:
The Journal of Power Sources is a publication catering to researchers and technologists interested in various aspects of the science, technology, and applications of electrochemical power sources. It covers original research and reviews on primary and secondary batteries, fuel cells, supercapacitors, and photo-electrochemical cells.
Topics considered include the research, development and applications of nanomaterials and novel componentry for these devices. Examples of applications of these electrochemical power sources include:
• Portable electronics
• Electric and Hybrid Electric Vehicles
• Uninterruptible Power Supply (UPS) systems
• Storage of renewable energy
• Satellites and deep space probes
• Boats and ships, drones and aircrafts
• Wearable energy storage systems