▎ 摘　　要

Based on density functional theory calculations, the full hydrolysis of per NH3BH3 molecule to produce three hydrogen molecules on single Pt atoms supported on oxidized graphene (Pt-1/Gr-O) is investigated. It is suggested that the first hydrogen molecule is produced by the combination of two hydrogen atoms from two successive B-H bonds breaking. Then one H2O molecule attacks the left *BHNH3 group (*represents adsorbed state) to form *BH(H2O)NH3 and the elongated O-H bond is easily broken to produce *BH(OH)NH3. The second H2O molecule attacks *BH(OH)NH3 to form *BH(OH)(H2O)NH3 and the breaking of O-H bond pointing to the plane of Pt-1/Gr-O results in the desorption of BH(OH)(2)NH3. The second hydrogen molecule is produced from two hydrogen atoms coming from two H2O molecules and Pt-1/Gr-O is recovered after the releasing of hydrogen molecule. The third hydrogen molecule is generated by the further hydrolysis of BH(OH)(2)NH3 in water solution. The rate-limiting step of the whole process is the combination of one H2O molecule and *BHNH3 with an energy barrier of 16.1 kcal/mol. Thus, Pt-1/Gr-O is suggested to be a promising catalyst for hydrolysis of NH3BH3 at room temperature.