Synergistic catalysis of MCM-41 immobilized Cu-Ni nanoparticles in hydrolytic dehydrogeneration of ammonia borane

Bimetallic Cu-Ni nanoparticles (NPs) were successfully immobilized in MCM-41 using a simple liquid impregnation-reduction method. All the resulting composites Cu-Ni/MCM-41 catalysts with various contents of Cu-Ni, and in particular Cu0.2Ni0.8/MCM-41 sample, outperform the activity of monometallic Cu and Ni counterparts and pure bimetallic Cu0.2Ni0.8 NPs in hydrolytic dehydrogeneration of ammonia borane (AB) at room temperature. The Cu0.2Ni0.8/MCM-41 catalyst exhibits excellent catalytic activity with a total turnover frequency (TOP) value of 10.7 mol H-2 mol catalyst(-1) min(-1) and a low activation energy value of 38 kJ mol(-1) at room temperature. In addition, Cu0.2Co0.8/MCM-41 also exhibits excellent activity with a TOP value as high as 15.0 mol H-2 mol catalyst(-1) min(-1). This obtained activity represents the highest catalytic active of Cu-based monometallic and bimetallic catalysts up to now toward the hydrolytic dehydrogeneration of ammonia borane (AB). The unprecedented excellent activity has been successfully achieved thanks to the strong bimetallic synergistic effects among the Cu-Ni (or Co) NPs of the composites. Copyright (C) 2014, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.