A viable hydrogen-storage system based on selective formic acid decomposition with a ruthenium catalyst
A viable hydrogen-storage system based on selective formic acid decomposition with a ruthenium catalyst
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DOI：
10.1002/anie.200800320
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发表时间：
2008-01-01
影响因子：
16.6
通讯作者：
Laurenczy, Gabor
中科院分区：
文献类型：
--
作者：
Fellay, Celine;Dyson, Paul J.;Laurenczy, Gabor
出于环境和经济原因，氢是一种重要的替代能源原料，当与燃料电池技术结合时，可以实现非常高效的能量转换。 [1]尽管氢相对于化石燃料有很多优点，但氢作为运输燃料的实际使用主要由于储存和运输问题而受到限制。传统的储氢方法，例如高压气体容器和低温液体/气体容器，存在重量和安全问题。 [2]因此，人们正在进行大量研究来开发新材料，例如有效储存氢的金属氢化物 [2, 3] 和碳纳米结构 [4]，尽管迄今为止尚未找到完全令人满意的选择。含有 4.4 wt% 氢的甲酸及其共轭碱甲酸盐是众所周知的氢源 [5–7]，之前曾被报道为潜在的储氢材料。 [8]与其他基质相比，甲酸的优势在于仅形成气态产物 (H2/CO2)，从而防止副产物的积累，而副产物的积累是移动应用的限制。然而，到目前为止，潜在的应用一直受到催化剂再生要求、苛刻的反应条件和较差的选择性的限制。我们在此提出了一种使用水溶性均相催化剂从甲酸生产氢气的高效、完全选择性和稳健的系统。[9]使用亲水性钌基催化剂在水溶液中进行甲酸的分解，该催化剂由高水溶性配体间三磺化三苯基膦（TPPTS）与[Ru（H2O）6]2+或更方便地使用市售RuCl3生成。催化剂在使用前通过与甲酸钠和甲酸反应以及在宽范围的压力和温度下进行甲酸的催化分解来活化。生成的 H2/CO2 压力通常在 1 至 220 bar 之间，但在压力高达 750 bar 时未观察到催化活性受到抑制（详情请参阅支持信息）。甲酸分解速率随温度升高而增加，且完全
Hydrogen represents an important alternative energy feedstock for both environmental and economic reasons, and when combined with fuel-cell technology, very efficient energy conversion can be achieved.[1] Although the advantages of hydrogen over fossil fuels are numerous, the actual use of hydrogen as a transportation fuel is limited mainly because of storage and delivery problems. Conventional hydrogen-storage methods, such as high-pressure gas containers and cryogenic liquid/gas containers, have weight and safety issues.[2] Consequently, a great deal of research is being undertaken to develop new materials, such as metal hydrides [2, 3] and carbon nanostructures,[4] that store hydrogen efficiently, although no entirely satisfactory options have been found so far. Formic acid containing 4.4 wt% of hydrogen, as well as its conjugate base, formate salt, are well known sources of hydrogen [5–7] and have previously been reported as potential hydrogen-storage material.[8] Formic acid has the advantage over other substrates that only gaseous products are formed (H2/CO2), hence preventing the accumulation of by-products, which is a limitation for mobile applications. However, until now potential applications have been limited by catalyst regeneration requirements, by harsh reaction conditions, and by poor selectivity. We present herein an efficient, completely selective, and robust system for hydrogen production from formic acid using water-soluble homogeneous catalysts.[9]Decomposition of formic acid was carried out in aqueous solution using hydrophilic ruthenium-based catalysts, generated from the highly water-soluble ligand meta-trisulfonated triphenylphosphine (TPPTS) with either [Ru (H2O) 6] 2+ or, more conveniently, commercially available RuCl3. The catalysts were activated prior to use by reaction with sodium formate and formic acid and the catalytic decomposition of formic acid performed under a wide range of pressures and temperatures. The generated H2/CO2 pressure was typically between 1 and 220 bar, but no inhibition of catalytic activity was observed up to a pressure of 750 bar (see the Supporting Information for details). The rate of formic acid decomposition increased with temperature, and at all