General Strategy for Synthesis of Ordered Pt3M Intermetallics with Ultrasmall Particle Size. Issue 20 (18th March 2020)

• Record Type: Journal Article
• Authors: Zhang, Bentian; Fu, Gengtao; Li, Yutao; Liang, Lecheng; Grundish, Nicholas S.; Tang, Yawen; Goodenough, John B.; Cui, Zhiming
• Is Part Of: Angewandte Chemie international edition. Volume 59:Issue 20(2020)
• Page Start: 7857
• Page End: 7863
• Publication Date: 2020-03-18
• Subjects: intermetallic nanoparticles -- oxygen reduction reaction -- synthesis strategy -- ultrasmall particle size -- uniform distribution; Chemistry -- Periodicals; 540
• DOI: 10.1002/anie.201916260
• Languages: English
• ISSNs: 1433-7851

Abstract

Abstract: Controllable synthesis of atomically ordered intermetallic nanoparticles (NPs) is crucial to obtain superior electrocatalytic performance for fuel cell reactions, but still remains arduous. Herein, we demonstrate a novel and general hydrogel‐freeze drying strategy for the synthesis of reduced graphene oxide (rGO) supported Pt3 M (M=Mn, Cr, Fe, Co, etc.) intermetallic NPs (Pt3 M/rGO‐HF) with ultrasmall particle size (about 3 nm) and dramatic monodispersity. The formation of hydrogel prevents the aggregation of graphene oxide and significantly promotes their excellent dispersion, while a freeze‐drying can retain the hydrogel derived three‐dimensionally (3D) porous structure and immobilize the metal precursors with defined atomic ratio on GO support during solvent sublimation, which is not afforded by traditional oven drying. The subsequent annealing process produces rGO supported ultrasmall ordered Pt3 M intermetallic NPs (≈3 nm) due to confinement effect of 3D porous structure. Such Pt3 M intermetallic NPs exhibit the smallest particle size among the reported ordered Pt‐based intermetallic catalysts. A detailed study of the synthesis of ordered intermetallic Pt3 Mn/rGO catalyst is provided as an example of a generally applicable method. This study provides an economical and scalable route for the controlled synthesis of Pt‐based intermetallic catalysts, which can pave a way for the commercialization of fuel cell technologies. Abstract : A novel and general strategy for the synthesis of reduced graphene oxide (rGO) supported atomically ordered Pt3 M (M=Mn, Cr, Fe, Co, etc.) intermetallic nanoparticles is reported under the aid of freeze‐drying technology. This synthetic strategy is demonstrated to be effective for the preparation and handling of nanoparticles with controlled particle size and ordered phase.