Low-temperature control over deposition of ultrafine Pd nanoparticles on porous carbon nanosheets for highly efficient dehydrogenation of ammonia borane

Abstract

The search for simply synthetic strategies of small-size metal nanoparticles is of significant relevance but still faces challenges. In this paper, a method of lowtemperature regulation (LTR) of ultrafine palladium nanoparticles deposited on porous carbon nanosheets is proposed for efficient dehydrogenation of ammonia borane. The LTR method might relieve the sintering of metal particles, thereby resulting in ultrafine Pd nanoparticles of 1.7 nm and their high dispersion on porous carbon. As suggested by the catalytic experiments hereby, Pd/NPC-LTR contributes to higher turnover frequencies of ammonia borane hydrolysis relative to most Pd-based catalysts reported previously. Furthermore, the catalytic performance could be further enhanced by the addition of NaOH under the same reaction conditions, with the hydrolysis completion time shortened by 2.5 times. Moreover, the recycle tests reveal that Pd/NPC-LTR catalyst has good stability and reusability in the hydrolysis of ammonia borane, preserving 70% of its initial catalytic activity even after 10 recycles. The insights reported here can be easily extended to slick preparation and rational design of Pd-catalysts for practical applications. • Low-temperature control over deposition of Pd NPs without any complicated treatments. • Highly dispersed and ultrafine Pd NPs are well deposited on porous carbon nanosheets. • Good performance for catalytic dehydrogenation of ammonia borane. • Highly stability and reusability even after 10 recycles.