Reactions between Mg and H₂O could provide on-demand, high-purity hydrogen gas; however, the reaction rate is slow at ambient temperature. In this work, the hydrogen evolution of Mg in Mg(Ac)₂,Zn(Ac)₂, Co(Ac)₂, and Ni(Ac)₂ solution is examined. The formed Mg(OH)₂ precipitate pushes the chemical equation forward and induces a continuous reaction between Mg and water in Mg(Ac)₂. Approximately ~952 mL g⁻¹ hydrogen is obtained. Metallic Zn is detected in the whole process and almost no Zn(OH)₂ is detected in Zn(Ac)₂. Both Mg(OH)₂ and Co(OH)₂/Ni(OH)₂ are detected in Co(Ac)₂ and Ni(Ac)₂. Meanwhile, the generated magnetic Co and Ni not only compose the micro-galvanic cell with Mg but also catalyze the hydrogen evolution. The detected maximum H₂ volume in Co(Ac)₂ and Ni(Ac)₂ is 847 and 950 mL g⁻¹, respectively. Correspondingly, the reaction rate varies from 54 to 275 mL g⁻¹ min⁻¹ in Co(Ac)₂ and 22 to 45 mL g⁻¹ min⁻¹ in Ni(Ac)₂, suggesting that the catalytic capability of Co is better than that of Ni. However, the change of Co morphology seriously affects the catalytic capability compared with Ni. In short, the formed precipitate pushes the chemical reaction forward and Co or Ni catalyst accelerates hydrogen evolution.

中文翻译：

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在不同的醋酸盐溶液中促进金属析氢和 Mg 沉淀

Mg与H ₂ O的反应可以按需提供高纯度氢气；但是，在环境温度下反应速度很慢。_{在这项工作中，研究了 Mg 在 Mg(Ac) 2}、Zn(Ac) ₂、Co(Ac) ₂和 Ni(Ac) ₂溶液中的氢析出。形成的 Mg(OH) _{2沉淀物推动化学方程式向前并在 Mg(Ac) 2}中诱导 Mg 和水之间的连续反应。获得大约~952 mL g ^-1氢。整个过程中检测到金属Zn，在Zn(Ac) 2 中几乎没有检测到_{Zn (OH) 2}。Mg(OH) ₂和 Co(OH) ₂在Co(Ac) ₂和Ni(Ac) ₂中检测到/Ni(OH) ₂。同时，产生的磁性Co和Ni不仅与Mg组成微原电池，而且还催化析氢。_{Co(Ac) 2}和Ni(Ac) ₂中检测到的最大H ₂体积分别为847和950 mL g ^-1。相应地，反应速率在 Co(Ac) ₂中从 54 到 275 mL g ^-1  min ^-1和在 Ni(Ac) ₂中从22 到 45 mL g ^-1  min ^-1不等, 表明 Co 的催化能力优于 Ni。然而，与 Ni 相比，Co 形态的变化严重影响了催化能力。简而言之，形成的沉淀物推动了化学反应的进行，而钴或镍催化剂加速了氢的析出。