铁粉为原料催化改性铁氧化物的储氢性能

以Fe粉为原料, 以金属Mo, Al和Ni可溶性盐作为添加剂, 通过浸渍法制备单金属添加和双金属添加的改性铁氧化物储氢材料Fe-Mo, Fe-Al, Fe-Mo-Ni和Fe-Mo-Al, 并研究了它们的储氢性能. 结果表明样品Fe-Mo改性效果最好: 如放氢温度由改性前的500 ℃降至改性后的290 ℃左右; 300 ℃时放氢速率最高, 由改性前的低于50 μmol?min^－1? Fe-g^－1到改性后的325 μmol?min^－1?Fe-g^－1 (10次平均); 4.53 wt%的平均实验储氢量与理论值4.8 wt%较接近; 储-放氢循环稳定性随着循环次数的增加呈逐渐增加的趋势. SEM微观结构和BET比表面积分析表明添加剂的种类对样品的改性作用更重要.

Properties of Hydrogen Storage for Catalytic Modified Iron Oxide Using Fe-powder as Starting Material

Modified iron oxides with single- or double-metal-cation-additive (Fe-Mo, Fe-Al, Fe-Mo-Ni, and Fe-Mo-Al) for hydrogen storage were prepared by an impregnation method using Fe powder as a starting material and their performances of hydrogen storage were investigated in detail. The results show that among all 4 cation-modified samples, the Mo-modified sample is the most favorable one; for example, the temperature of H₂ formation for the Fe-Mo was obviously decreased from 500 ℃ before the addition of Mo to 290 ℃ after the addition of Mo, while the rate of H₂ formation was remarkably enhanced from 50 μmol?min^－1?Fe-g^－1 to 325 μmol?min^－1?Fe-g^－1 (average value of 10 cycles) at 300 ℃; the average capacity of hydrogen storage reached 4.53 wt%, closed to theoretical value 4.8 wt%; the cyclic stability of re-oxidation increased with increasing the number of cycles. In addition, the results of SEM and BET surface area show that the kind of metal cation added to Fe powder is more important for the samples to be modified.