Visible-light-enhanced catalytic hydrolysis of ammonia borane using RuP_2 quantum dots supported by graphitic carbon nitride

摘要

Hydrolytic dehydrogenation of ammonia borane (AB) driven by efficient catalysts has attracted considerable attention and is regarded as a promising strategy for hydrogen generation. Herein, RuP2 quantum dots supported on graphitic carbon nitride (g-C3N4) were successfully prepared by in-situ phosphorization, yielding a highly efficient photocatalyst toward AB hydrolysis. The catalysts were characterized by field-emission scanning electron microscopy, transmission electron microscopy, x-ray diffraction, x-ray photoelectron microscopy, inductively coupled plasma atomic emission spectroscopy, UV-visible diffuse reflectance spectroscopy and photoluminescence spectroscopy. A conventional waterdisplacement method was employed to record the hydrogen volume as a function of reaction time. Owing to visible-light irradiation, the initial turnover frequency of the AB hydrolysis was significantly enhanced by 110% (i.e., 134 min(-1)) at room temperature. Furthermore, the apparent activation energy decreased from 67.7 +/- 0.9 to 47.6 +/- 1.0 kJ mol(-1). The photocatalytic hydrolysis mechanism and catalyst reusability were also investigated. (C) 2020 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.