PVP-Adjusted Crystal Surfaces of PtPd Nanoparticles for Enhancing the Catalytic Hydrolysis of Ammonia Borane

In recent years, the morphology control of nanoparticles (NPs) has been an effective way to improve the catalytic performance of PtPd alloys. Polyvinylpyrrolidone (PVP) can be used as a multifunctional orientation and stabilizer for monodisperse nanostructure synthesis. In ethylene glycol (EG), PVP stabilizes the crystal plane by the interaction of the carbonyl group of the repeating unit with the metal surface. In this article, a series of Pt, Pd, and PtPd alloy NPs with different morphologies within 10 nm were synthesized by changing the content of PVP to explore the effects of different crystal plane exposure ratios on the morphology. The DFT results showed that different PVP contents would expose different crystal planes of NPs. The NPs exposed to different crystal planes have different effects on the hydrolysis performance of ammonia borane (AB). An appropriate {100}/{111} ratio was conducive to the adsorption of H2O and the desorption of H2 so as to promote the hydrolysis of AB. The morphology adjustment has endowed PtPd alloy NPs with superior AB hydrolysis performance. This work provides more insights for improving catalytic performance through the control of the morphology and crystal plane.