Stabilization of Exposed Metal Nanocrystals in High‐Temperature Heterogeneous Catalysis

• Published in: Advanced materials (Weinheim) Vol. 34; no. 6; pp. e2108727 - n/a
• Main Authors: Zhu, Zhijie, Feng, Kai, Li, Chaoran, Tang, Rui, Xiao, Mengqi, Song, Rui, Yang, Di, Yan, Binhang, He, Le
• Format: Journal Article
• Language: English
• Published: Germany Wiley Subscription Services, Inc 01.02.2022
• Subjects: Catalysis; Catalysts; colloidal nanocrystals; Colloids; high‐temperature heterogeneous catalysis; Materials science; metal nanocrystals; Nanocrystals; Operating temperature; reverse water gas shift; Selectivity; Silicon dioxide; stabilization; Temperature; Water gas; reverse water gas shift; high-temperature heterogeneous catalysis; stabilization; metal nanocrystals; colloidal nanocrystals
• ISSN: 0935-9648; 1521-4095
• DOI: 10.1002/adma.202108727

Colloidal metal nanocrystals with uniform sizes, shapes, compositions, and architectures are ideal building blocks for constructing heterogeneous catalysts with well‐defined characteristics toward the investigation of accurate structure–property relationships and better understanding of catalytic mechanism. However, their applications in high‐temperature heterogeneous catalysis are often restricted by the difficulty in maintaining the high metal dispersity and easy accessibility to active sites under harsh operating conditions. Here, a partial‐oxide‐coating strategy is proposed to stabilize metal nanocrystals against sintering and meanwhile enable an effective exposure of active sites. As a proof‐of‐concept, controlled partial silica coating of colloidally prepared Pd0.82Ni0.18 nanocrystals with the size of 8 nm is demonstrated. This partially coated catalyst exhibits excellent activity, selectivity, and stability, outperforming its counterparts with fully coated and supported structures, in reverse water gas shift (RWGS) catalysis particularly at high operating temperatures. This study opens a new avenue for the exploration of colloidal metal nanocrystals in high‐temperature heterogeneous catalysis. A partial oxide coating strategy is developed for the stabilization of exposed metal nanocrystals to enhance their performance in thermal reverse water gas shift (RWGS) catalysis particularly at high temperatures. This study opens a new avenue for the exploration of high‐quality colloidal metal nanocrystals in high‐temperature heterogeneous catalysis.