Pd-Modified ZnO–Au Enabling Alkoxy Intermediates Formation and Dehydrogenation for Photocatalytic Conversion of Methane to Ethylene

• DOI: 10.1021/jacs.0c10369
• Publication Date: 2020-12-29T21:51:07Z
• Authors: Wenbin Jiang; Jingxiang Low; Keke Mao; Delong Duan; Shuangming Chen; Wei Liu; Chih-Wen Pao; Jun Ma; Shuaikang Sang; Chang Shu; Xiaoyi Zhan; Zeming Qi; Hui Zhang; Zhi Liu; Xiaojun Wu; Ran Long; Li Song; Yujie Xiong
• Keywords: 01 natural sciences; 7. Clean energy; 0104 chemical sciences

Photocatalysis provides an intriguing approach for the conversion of methane to multicarbon (C2+) compounds under mild conditions; however, with methyl radicals as sole reaction intermediate, current C2+ products are dominated by ethane, a negligible selectivity toward ethylene, which, key chemical feedstock, possesses higher added value than ethane. Herein, we report direct photocatalytic methane-to-ethylene pathway involving formation and dehydrogenation alkoxy (i.e., methoxy ethoxy) intermediates over Pd-modified ZnO–Au hybrid catalyst. On basis various in situ characterizations, it is revealed that Pd-induced capability catalyst holds turning on pathway. During reaction, molecules first dissociated into surface ZnO assistance Pd. Then these further dehydrogenated coupled radical ethoxy, which can be subsequently converted ethylene through dehydrogenation. As result, optimized ZnO–AuPd atomically dispersed Pd sites Au lattice achieves 536.0 μmol g–1 compound 96.0% (39.7% C2H4 54.9% C2H6 total produced compounds) after 8 h light irradiation. This work fresh insight conditions highlights significance enhanced activity unsaturated hydrocarbon product selectivity.