Synthesis of rattle-structured CuCo2O4 nanospheres with tunable sizes based on heterogeneous contraction and their ultrahigh performance toward ammonia borane hydrolysis

Micro/nano-materials with rattle-type structures are attractive because of their unique physicochemical properties and extensive applications. In this study, well-defined rattle-type CuCo2O4 nanospheres were fabricated by heterogeneous contraction caused by non-equilibrium heat treatment with the assistance of an RF (resorcinol formaldehyde) resin colloidal sphere hard template. The sizes of CuCo2O4 nanospheres could be tuned by varying the amount of NH3 center dot H2O used during template synthesis. The possible formation mechanism of rattle-type CuCo2O4 nanospheres was also proposed. When used in ammonia borane hydrolysis, rattle-type CuCo2O4 nanospheres exhibited ultrahigh activity with a turnover frequency of 104.0 min(-1), which is one of the highest activities of non-noble-metal based catalysts, and is even higher than many noble-metal-based catalysts. This research provides valuable insights into the development of robust catalysts for ammonia borane hydrolysis. In addition, the synthetic method presented in this work can be easily extended to prepare other oxide composites with rattle structures. (C) 2020 Elsevier B.V. All rights reserved.

Automated summary

Well-defined rattle-type CuCo2O4 nanospheres were fabricated in this study, showing ultrahigh activity in ammonia borane hydrolysis. The research provides valuable insights for the development of future catalysts.