Activating Co nanoparticles on graphitic carbon nitride via tuning the Schottky barrier by P doping for the efficient dehydrogenation of ammonia-borane

A highly active Mott-Schottky nanocatalyst with tunable Schottky barrier was constructed by embedding Co nanoparticles (NPs) onto phosphorus-doped graphitic carbon nitrides (PxCN) for the enhanced dehydrogenation of ammonia-borane (AB). The analyses show that the P doping can efficiently decrease the work function of g-C3N4 and elevate the conduction band edge potential, which in turns offering a simple approach to tune the Schottky barrier of Co/PxCN by variation the amount of doped-P atoms. By rationally tuning the Schottky barrier from 0.60 to 0.78 eV, the obtained photocatalyst with the molar composition of Co/P3.59CN shows remarkable activity of TOF (total turnover frequency) value of 67.09 mol H2 mol-1 metal min-1 for the dehydrogenation of AB under visible light at 298 K, which is one of the highest values reported among the non-noble metal based monometallic catalyst to the best of my knowledge, and is even comparable to some noble metal catalysts. This work will open a new vista to rational design and prepare metal/g-C3N4 nanocatalysts with tunable Schottky barrier and gives an expect to elevate their catalytic activity by a simple way.