Li Jinlong, Ren Xueying, Lv Hao, Wang Yingying, Li Yafei, Liu Ben
Jiangsu Key Laboratory of New Power Batteries, Jiangsu Collaborative Innovation Center of Biomedical Functional Materials, School of Chemistry and Materials Science, Nanjing Normal University, Nanjing, 210023, China.
Jiangsu Key Laboratory of New Power Batteries, Jiangsu Collaborative Innovation Center of Biomedical Functional Materials, School of Chemistry and Materials Science, Nanjing Normal University, Nanjing, 210023, China.
J Hazard Mater. 2020 Jun 5;391:122199. doi: 10.1016/j.jhazmat.2020.122199. Epub 2020 Jan 31.
Designing highly efficient and cheap nanocatalysts for room-temperature hydrolysis of ammonia borane (AB) is of great significance for their real application in hydrogen (H)-based fuel cells. Here, we report a kind of noble metal (NM)-free hybrid nanocatalysts composed of heterostructured Cu@CuCoO nanoparticles and a graphene oxide support (denoted as Cu@CuCoO@GO) and demonstrate their high catalytic performance toward the hydrolysis of AB. By rationally controlling synthetic parameters, we find that optimum Cu@CuCoO@GO achieves a superior catalytic activity with a turnover frequency of 44.6 mol mol min in HO and 98.2 mol mol min in 0.2 M NaOH, better than most of previously reported NM-free nanocatalysts. This catalyst also discloses a very low activation energy (E) of 35.4 kJ mol. The studies on catalytic kinetics and isotopic experiments attribute the high activity to synergistically structural and compositional advantages of Cu@CuCoO@GO, which kinetically accelerates the oxidative cleavage of OH bond in attacked HO (the rate-determining step of the hydrolysis of AB). This study thus provides an opportunity for rational design of cheap NM-free nanocatalysts for H production from chemical H-storage materials.
设计高效且廉价的用于氨硼烷（AB）室温水解的纳米催化剂对于其在氢基燃料电池中的实际应用具有重要意义。在此，我们报道了一种由异质结构的Cu@CuCoO纳米颗粒和氧化石墨烯载体组成的无贵金属（NM）杂化纳米催化剂（表示为Cu@CuCoO@GO），并展示了它们对AB水解的高催化性能。通过合理控制合成参数，我们发现最佳的Cu@CuCoO@GO在水中实现了44.6 mol mol⁻¹ min⁻¹的周转频率，在0.2 M NaOH中为98.2 mol mol⁻¹ min⁻¹，具有优异的催化活性，优于大多数先前报道的无NM纳米催化剂。该催化剂还揭示了极低的35.4 kJ mol⁻¹的活化能（Ea）。催化动力学研究和同位素实验将高活性归因于Cu@CuCoO@GO的结构和组成协同优势，这在动力学上加速了被攻击的H₂O中O-H键的氧化裂解（AB水解的速率决定步骤）。因此，本研究为合理设计用于从化学储氢材料制氢的廉价无NM纳米催化剂提供了契机。
