Li Tianbo, Liu Fei, Tang Yan, Li Lin, Miao Shu, Su Yang, Zhang Junying, Huang Jiahui, Sun Hui, Haruta Masatake, Wang Aiqin, Qiao Botao, Li Jun, Zhang Tao
Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China.
University of Chinese Academy of Sciences, Beijing, 100049, China.
Angew Chem Int Ed Engl. 2018 Jun 25;57(26):7795-7799. doi: 10.1002/anie.201803272. Epub 2018 May 18.
The solvent-free selective oxidation of alcohols to aldehydes with molecular oxygen is highly attractive yet challenging. Interfacial sites between a metal and an oxide support are crucial in determining the activity and selectivity of such heterogeneous catalysts. Herein, we demonstrate that the use of supported single-atom catalysts (SACs) leads to high activity and selectivity in this reaction. The significantly increased number of interfacial sites, resulting from the presence of individually dispersed metal atoms on the support, renders SACs one or two orders of magnitude more active than the corresponding nanoparticle (NP) catalysts. Lattice oxygen atoms activated at interfacial sites were found to be more selective than O activated on metal NPs in oxidizing the alcohol substrate. This work demonstrates for the first time that the number of interfacial sites is maximized in SACs, providing a new avenue for improving catalytic performance by developing appropriate SACs for alcohol oxidation and other reactions occurring at metal-support interfacial sites.
利用分子氧将醇无溶剂选择性氧化为醛极具吸引力，但也具有挑战性。金属与氧化物载体之间的界面位点对于确定此类多相催化剂的活性和选择性至关重要。在此，我们证明使用负载型单原子催化剂（SAC）可使该反应具有高活性和选择性。由于载体上单个分散的金属原子的存在，界面位点数量显著增加，使得SAC的活性比相应的纳米颗粒（NP）催化剂高一个或两个数量级。发现在界面位点活化的晶格氧原子在氧化醇底物时比在金属NP上活化的O更具选择性。这项工作首次证明SAC中的界面位点数量达到最大化，为通过开发适用于醇氧化及其他在金属-载体界面位点发生的反应的SAC来提高催化性能提供了一条新途径。
