General negative pressure annealing approach for creating ultra-high-loading single atom catalyst libraries

作者：Yi Wang, Chongao Li, Xiao Han, Jintao Bai, Xuejing Wang, Lirong Zheng, Chunxia Hong, Zhijun Li, Jinbo Bai, Kunyue Leng, Yue Lin, Yunteng Qu · 发表于：Nature Communications · 年份：2024 · DOI：10.1038/s41467-024-50061-1 · 被引用次数：93 · 研究领域：Catalytic Processes in Materials Science、Electrocatalysts for Energy Conversion、Catalysis and Oxidation Reactions

Catalyst systems populated by high-density single atoms are crucial for improving catalytic activity and selectivity, which can potentially maximize the industrial prospects of heterogeneous single-atom catalysts (SACs). However, achieving high-loading SACs with metal contents above 10 wt% remains challenging. Here we describe a general negative pressure annealing strategy to fabricate ultrahigh-loading SACs with metal contents up to 27.3-44.8 wt% for 13 different metals on a typical carbon nitride matrix. Furthermore, our approach enables the synthesis of high-entropy single-atom catalysts (HESACs) that exhibit the coexistence of multiple metal single atoms with high metal contents. In-situ aberration-corrected HAADF-STEM (AC-STEM) combined with ex-situ X-ray absorption fine structure (XAFS) demonstrate that the negative pressure annealing treatment accelerates the removal of anionic ligand in metal precursors and boosts the bonding of metal species with N defective sites, enabling the formation of dense N-coordinated metal sites. Increasing metal loading on a platinum (Pt) SAC to 41.8 wt% significantly enhances the activity of propane oxidation towards liquid products, including acetone, methanol, and acetic acid et al. This work presents a straightforward and universal approach for achieving many low-cost and high-density SACs for efficient catalytic transformations.