Alloyed palladium-nickel hollow nanospheres with interatomic charge polarization for improved hydrolytic dehydrogenation of ammonia borane. (4th January 2018)

• Record Type: Journal Article
• Authors: Du, Yuanxin; Wang, Kun; Zhai, Qingxi; Chen, Akang; Xi, Zhiwei; Yan, Jian; Kang, Xi; Chen, Man; Yuan, Xiaoyou; Zhu, Manzhou
• Is Part Of: International journal of hydrogen energy. Volume 43:Number 1(2018)
• Page Start: 283
• Page End: 292
• Publication Date: 2018-01-04
• Subjects: Palladium-nickel hollow nanospheres -- Hydrolytic dehydrogenation -- Ammonia borane -- Synergistic mechanism -- First-principles calculation; Hydrogen as fuel -- Periodicals; Hydrogène (Combustible) -- Périodiques; Hydrogen as fuel; Periodicals; 665.81
• DOI: 10.1016/j.ijhydene.2017.11.066
• Languages: English
• ISSNs: 0360-3199

Abstract

Abstract: Hydrolysis reaction of ammonia borane (AB) has been considered as a safe and efficient hydrogen generation method, in which designing cost-effective and high-performance catalysts plays vital role. In this work, we have developed well dispersed palladium-nickel hollow nanospheres (PdNi HNSs) with tunable shell thickness and compositions via a facile galvanic replacement approach. The as-prepared PdNi HNSs show composition-dependent catalysis in the hydrolytic dehydrogenation of AB. The Pd84 Ni16 /C exhibiting sphere-shaped hollow interiors with average 70 nm particle size and 10 nm thin wall, presents the highest catalytic activity with the turnover frequency of 76.0 (mol H2 min −1 (mol Pd) −1 ) and the activation energy of 33.5 kJ mol −1 . The superior catalytic effect of PdNi HNSs in enhancing hydrolysis efficiency of AB can be ascribed to two major factors: (1) high active surface areas of the unique hollow structure; (2) enhanced H adsorption attributed to the coupling between Pd and Ni induces polarization charges on Pd catalytic sites, which is indicated by the first-principles calculation and X-ray photoelectron spectroscopy studies. Furthermore, the catalysts exert good long-term recycling stability and catalytic activity for the hydrolytic dehydrogenation of AB. This work represents a strategy may hopefully be extended to synthesize other Pd-based hollow nanostructure with reduced Pd usage and increased catalytic active sites, and also sheds light on the exploration of utilizing interatomic interactions to regulate species adsorption/activation for highly efficient catalytic performance. Graphical abstract: Highlights: Synthesis of PdNi hollow nanospheres with tunable shell thickness and compositions. The Pd84 Ni16 /C presents enhanced catalytic activity in ammonia borane hydrolysis. High active surface area of hollow structure is benefit for catalytic activity. Interatomic charge polarization also promotes the catalytic efficiency.