Morphology engineering of hollow core@shell structured Co3O4@CuO-NiO for fast hydrogen release from ammonia borane methanolysis

Catalytic methanolysis of ammonia borane is an integrated hydrogen production/storage technology with bright prospects, while its wide application is impeded by the high-cost of catalysts. In this work, hollow core@shell structured (HCSS) Co 3 O 4 @CuO-NiO with a size of 300–500 nm and a shell thickness of ca. 100 nm has been designed for ammonia borane (NH 3 BH 3 ) methanolysis for rapid hydrogen release. The possible formation mechanism of HCSS-Co 3 O 4 @CuO-NiO is proposed based on a series of characterization results, which is crucial for the design and preparation of nanocatalysts with similar architectures. Benefiting from the optimized compositions and electronic structures, the best HCSS-Co 3 O 4 @CuO-NiO sample exhibits high catalytic activity in NH 3 BH 3 methanolysis with a turnover frequency of 67.1 min −1 , surpassing that of all the noble-metal-free catalysts in previous reports. A possible reaction mechanism of NH 3 BH 3 methanolysis is put forward based on the in-situ Fourier transform infrared spectrometer (FTIR) characterization and kinetic isotope effect (KIE) experimental results. This work supplies a novel avenue for developing cheap and robust catalysts towards NH 3 BH 3 methanolysis by tailoring the catalysts’ morphology to hollow core@shell structures.