海水制氢Al-Mg-Ga-Sn合金的研究

Hydrogen Production Behavior of Al-Mg-Ga-Sn Alloy in Seawater

摘要:

采用铸造法制备6种Al-Mg-Ga-Sn合金。研究该类合金在模拟海水(3.5%NaCl)溶液中,30℃、50℃、70℃和90℃下的产氢行为,定量分析产氢速率、产氢量、能量密度和转化率。从组织结构和电化学角度进行了定性分析。采用XRD结合SEM分析发现：Al-Mg-Ga-Sn合金主要组成相与Al/Ga比值有关,Al/Ga＝17/1合金有Alss、Mg₂Sn；Al/Ga≤14/1合金有Alss、Mg₂Sn和Ga₅Mg₂；Al-Mg-Ga-Sn合金/海水反应产物除NaCl外,30℃～70℃时产物为Alss、Mg₂Sn和Al(OH)₃；90℃时产物为Alss和AlO(OH)。室温下,Al-Mg-Ga-Sn合金在3.5%NaCl溶液中的极化电阻随Al/Ga比值增大逐渐增大；且腐蚀电流与组织结构相关。在90℃,Al/Ga=8/1时,产氢速率19.36mL/(min?g),产氢量1.156×10^₃mL/g,能量密度3.515×10^₁₀J/m^₃,转换率达97.6％。

Abstract:

Al-Mg-Ga-Sn alloys with six different Al/Ga weight ratio were prepared by casting. The hydrogen production behavior of these alloys in simulated seawater (3.5% NaCl) solution at 30 ° C, 50 ° C, 70 ° C and 90 ° C was investigated, respectively, where quantitative analysis of hydrogen production rate, hydrogen yield, energy density and conversion rate, and qualitative analysis of microstructure and electrochemical performance were conducted. XRD analysis combined with SEM revealed that composition phase of Al-Mg-Ga-Sn alloys are related to the Al/Ga weight ratio. If Al/Ga＝17/1, Alss and Mg₂Sn dominate; if Al/Ga≤14/1, composition phases contain Alss, Mg₂Sn and Ga₅Mg₂. In addition to NaCl, the reaction product of Al-Mg-Ga-Sn alloy/seawater include Alss、Mg₂Sn and Al(OH)₃ at 30 °C-70 °C; and Alss, and AlO(OH) at 90 °C. The polarization resistance of Al-Mg-Ga-Sn alloy in the 3.5%NaCl solution at room temperature gradually increases as the Al/Ga ratio increases, and the corrosion current is related to the microstructure. At 90 ° C, when Al/Ga = 8 / 1, hydrogen production rate is 19.36mL / (min ? g), hydrogen yield is 1.156×10^₃ mL / g, energy density is 3.515×10^₁₀J / m^₃, and conversion rate is up to 97.6%.