Metal-Organic Framework (MOF)-Derived Electron-Transfer Enhanced Homogeneous PdO-Rich Co O as a Highly Efficient Bifunctional Catalyst for Sodium Borohydride Hydrolysis and 4-Nitrophenol Reduction.

Developing a bifunctional catalyst with low cost and high catalytic performance in NaBH hydrolysis for H generation and selective reduction of nitroaromatics will make a significant impact in the field of sustainable energy and water purification. Herein, a low-loading homogeneously dispersed Pd oxide-rich Co O polyhedral catalyst (PdO-Co O ) with concave structure is reported by using a metal-organic framework (MOF)-templated synthesis method. The results show that the PdO-Co O catalyst has an exceptional turnover frequency (3325.6 mol  min  mol ), low activation energy (43.2 kJ mol ), and reasonable reusability in catalytic H generation from NaBH hydrolysis. Moreover, the optimized catalyst also shows excellent catalytic performance in the NaBH selective reduction of 4-nitrophenol to 4-aminiphenol with a high first-order reaction rate of approximately 1.31 min . These excellent catalytic properties are mainly ascribed to the porous concave structure, monodispersed Pd oxide, as well as the unique synergy between PdO and Co O species, which result in a large specific surface area, high conductivity, and fast solute transport and gas emissions.