Robust 3D boron nitride nanoscaffolds with interconnected mesoporous networks, high surface areas and pore volumes for remarkable hydrogen storage capacity from ammonia borane (Conference Presentation)

Abstract

Hydrogen is an environmentally friendly energy carrier and its one of the most promising alternatives to the current traditional fossil-fuel based technologies. Hydrogen economy is currently hindered by a set of issues regarding production, distribution and end use and its storage has become one of the most arduous issues in the past few years. In this work, we report a novel synthesis routine for mesoporous monolythic boron nitride (BN) nanostructures based on a template assisted polymer-derived ceramic route. Polyborazylene has been used in order to impregnate monolithic activated carbon used as templates. After pyrolysis and template removal, BN polyhedral have been obtained, with controlled crystallinity and tunable textural properties, which highly depend on the annealing temperature. High-resolution Transmission Electron Microscopy analysis has shown that our synthesis routine has resulted in monoliths with an interconnected mesoporous network as well as high surface areas ranging from 584 to 728 m2·g-1, high pore volumes (0.75 to 0.93 cm3 · g-1) and high compressive strengths. Furthermore, we demonstrate the use of these highly porous compounds as nanoscaffolds to confine ammonia borane with the objective to enhance its dehydrogenation properties. The as formed composites are able to release pure H2 at low temperatures (1000 C) and show a remarkable effective gravimetric hydrogen storage capacity up to 8.1 wt. % based on measurement of ammonia borane. This demonstrates the remarkable potential of this system as a potential hydrogen storage material.