Hydrolysis of Ammonia Borane on a Single Pt Atom Supported by N-Doped Graphene.

The hydrolysis of ammonia borane (NH 3 BH 3 or AB) at room temperature is a promising method to produce hydrogen, but the complete reaction mechanism is still less investigated. Herein, the full hydrolysis process of the AB molecule on single Pt atom coordinated by two carbon atoms and one nitrogen atom (Pt 1 -C 2 N 1 ) on nitrogen doped graphene is investigated using the density functional theory (DFT) method. Our results demonstrate that the rate-limiting step is the formation of *BH 2 NH 3 by breaking the first B-H bond in AB with an energy barrier of 0.68 eV, implying that Pt 1 -C 2 N 1 is a potential room-temperature catalyst for the full hydrolysis of AB. In addition, 27 more types of M 1 -C 2 N 1 (M represents transiton metal atom) and Pt 1 supported on nitrogen-doped graphene with different local coordination environments (Pt 1 -C x N y , x and y are the number of carbon and nitrogen atoms that coordinated with the platinum atom) are considered to screen out potential single-atom catalysts for AB hydrolysis. The screening results further show that Pt 1 -C 1 N 2 is another potential catalyst for AB hydrolysis. In particular, two hydrogen atoms precovered on Pt 1 -C 1 N 2 , resulting in a lower energy barrier for the rate-limiting step than that on Pt 1 -C 2 N 1 . This study provides a prototype of Pt 1 -C 1 N 2 and Pt 1 -C 2 N 1 for catalytic full hydrolysis of AB at room temperature.