Baldé Cornelis P, Hereijgers Bart P C, Bitter Johannes H, de Jong Krijn P
Inorganic Chemistry and Catalysis, Department of Chemistry, Utrecht University, 3584 CA Utrecht, The Netherlands.
J Am Chem Soc. 2008 May 28;130(21):6761-5. doi: 10.1021/ja710667v. Epub 2008 May 7.
Important limitations in the application of light metal hydrides for hydrogen storage are slow kinetics and poor reversibility. To alleviate these problems doping and ball-milling are commonly applied, for NaAlH 4 leading to particle sizes down to 150 nm. By wet-chemical synthesis we have prepared carbon nanofiber-supported NaAlH 4 with discrete particle size ranges of 1-10 microm, 19-30 nm, and 2-10 nm. The hydrogen desorption temperatures and activation energies decreased from 186 degrees C and 116 kJ.mol (-1) for the largest particles to 70 degrees C and 58 kJ.mol (-1) for the smallest particles. In addition, decreasing particle sizes lowered the pressures needed for reloading. This reported size-performance correlation for NaAlH 4 may guide hydrogen storage research for a wide range of nanostructured light (metal) hydrides.
轻金属氢化物在储氢应用中的重要局限性是动力学缓慢和可逆性差。为了缓解这些问题，通常采用掺杂和球磨方法，对于NaAlH4，可使颗粒尺寸降至150纳米。通过湿化学合成，我们制备了碳纳米纤维负载的NaAlH4，其离散粒径范围为1-10微米、19-30纳米和2-10纳米。氢解吸温度和活化能从最大颗粒的186℃和116kJ.mol（-1）降至最小颗粒的70℃和58kJ.mol（-1）。此外，减小颗粒尺寸降低了再装填所需的压力。报道的NaAlH4的这种尺寸-性能相关性可能会指导广泛的纳米结构轻（金属）氢化物的储氢研究。
