Ozerova Anna M, Skobelkina Anastasia A, Simagina Valentina I, Komova Oksana V, Prosvirin Igor P, Bulavchenko Olga A, Lipatnikova Inna L, Netskina Olga V
Boreskov Institute of Catalysis SB RAS, Lavrentiev Ave. 5, 630090 Novosibirsk, Russia.
Materials (Basel). 2022 Apr 21;15(9):3010. doi: 10.3390/ma15093010.
Magnetically recovered Co and Co@Pt catalysts for H generation during NaBH hydrolysis were successfully synthesized by optimizing the conditions of galvanic replacement method. Commercial aluminum particles with an average size of 80 µm were used as a template for the synthesis of hollow shells of metallic cobalt. Prepared Co was also subjected to galvanic replacement reaction to deposit a Pt layer. X-ray diffraction analysis, X-ray photoelectron spectroscopy, scanning electron microscopy, and elemental analysis were used to investigate catalysts at each stage of their synthesis and after catalytic tests. It was established that Co hollow microshells show a high hydrogen-generation rate of 1560 mL·min·g at 40 °C, comparable to that of many magnetic cobalt nanocatalysts. The modification of their surface by platinum (up to 19 at% Pt) linearly increases the catalytic activity up to 5.2 times. The catalysts prepared by the galvanic replacement method are highly stable during cycling. Thus, after recycling and washing off the resulting borate layer, the Co@Pt catalyst with a minimum Pt loading (0.2 at%) exhibits an increase in activity of 34% compared to the initial value. The study shows the activation of the catalyst in the reaction medium with the formation of cobalt-boron-containing active phases.
通过优化电置换法的条件,成功合成了用于硼氢化钠水解制氢的磁性回收钴和钴@铂催化剂。使用平均粒径为80 µm的商用铝颗粒作为合成金属钴空心壳的模板。制备的钴也进行了电置换反应以沉积铂层。利用X射线衍射分析、X射线光电子能谱、扫描电子显微镜和元素分析对催化剂合成的各个阶段以及催化测试后的催化剂进行了研究。结果表明,钴空心微壳在40℃下显示出1560 mL·min·g的高产氢速率,与许多磁性钴纳米催化剂相当。用铂对其表面进行改性(铂含量高达19 at%)可使催化活性线性提高至5.2倍。通过电置换法制备的催化剂在循环过程中高度稳定。因此,在回收并洗去生成的硼酸盐层后,最低铂负载量(0.2 at%)的钴@铂催化剂的活性比初始值提高了34%。该研究表明,在反应介质中催化剂会活化并形成含钴硼的活性相。