Abstract:

The Ru/WC-C catalyst was prepared by dispersing Ru on the WC-C support, and its catalytic performance in hydrogen generation from ammonia borane hydrolysis was tested. The phase structure, morphology and surface element state of the catalyst were characterized by X-ray diffraction, transmission electron microscopy and X-ray photoelectron spectroscopy. The results showed that Ru nanoparticles were evenly scattered on the surface and surroundings of WC, and the electronic synergy effect between the Ru and WC promoted the hydrogenation of ammonia and hydrolysis of ammonia. Under the condition of 298 K and alkaline solution environment, the hydrolysis performance of ammonia borane was related to the Ru content. With the increase of Ru content, the hydrogen production time was shortened. The completed hydrogen production time of 2%Ru/WC-C catalyst with a Ru mass fraction of 2% was 3.5 min, and its hydrogen generation rate value was 573.0 min^-1 with activation energy of 45.3 kJ·mol^-1. Moreover, its hydrogen generation rate value in the neutral aqueous solution was still as high as 136.2 min^-1. The application of WC-C carrier can effectively promote the activation of water molecules during the reaction, and then improve the catalytic performance of Ru catalyst. This study provides a new insight for the development of low-cost and efficient catalyst for hydrogen production from ammonia borane hydrolysis.

Key words: ammonia borane, hydrogen production, hydrolysis, nanomaterials, catalysis

摘要：

采用浸渍法将Ru分散在WC-C载体上制备了Ru/WC-C催化剂，测试了其氨硼烷水解制氢反应性能。通过X射线衍射、透射电子显微镜和X射线光电子能谱对催化剂的物相、形貌和表面元素状态进行了表征。结果表明，Ru均匀分散于WC的表面和周围，与WC之间的电子协同效应促进了氨硼烷水解制氢。在298 K，碱性溶液的条件下，氨硼烷水解反应性能与Ru的含量有关，随着Ru含量的增加，产氢时间缩短，Ru的质量分数为2%的2%Ru/WC-C催化剂完全产氢时间为3.5 min，其氢气的产氢速率值为573.0 min^-1，反应活化能为45.3 kJ·mol^-1。其在中性水溶液中氢气的产氢速率值仍高达136.2 min^-1。WC-C载体的应用可有效地促进反应过程中水分子的活化，进而改善Ru催化剂的性能，这为开发高效的氨硼烷水解制氢催化剂提供了新途径。

关键词: 氨硼烷, 制氢, 水解, 纳米材料, 催化作用