Synergistic interface between metal Cu nanoparticles and CoO for highly efficient hydrogen production from ammonia borane.

The development of efficient non-noble metal catalysts for the dehydrogenation of hydrogen (H 2 ) storage materials is highly desirable to enable the global production and storage of H 2 energy. In this study, Cu x -(CoO) 1- x /TiO 2 catalysts with a Cu-CoO interface supported on TiO 2 are shown to exhibit high catalytic efficiency for ammonia borane (NH 3 BH 3 ) hydrolysis to generate H 2 . The best catalytic activity was observed for a catalyst with a Cu : Co molar ratio of 1 : 1. The highest dehydrogenation turnover frequency (TOF) of 104.0 mol H 2 mol metal -1 min -1 was observed in 0.2 M NaOH at room temperature, surpassing most of the TOFs reported for non-noble catalysts for NH 3 BH 3 hydrolysis. Detailed characterisation of the catalysts revealed electronic interactions at the Cu-CoO heterostructured interface of the catalysts. This interface provides bifunctional synergetic sites for H 2 generation, where activation and adsorption of NH 3 BH 3 and H 2 O are accelerated on the surface of Cu and CoO, respectively. This study details an effective method of rationally designing non-noble metal catalysts for H 2 generation via a metal and transition-metal oxide interface.