Biphasic Ag block assisting electron and energy transfer to facilitate photothermal catalytic oxidation of HCHO over manganese oxide. (December 2019)

• Record Type: Journal Article
• Authors: Xu, Zhen; Chen, Jin; Cai, Songcai; Yan, Dongxu; Chen, Xi; Xu, Wenjian; Chen, Jing; Jia, Hongpeng
• Is Part Of: Materials today energy. Volume 14(2019)
• Publication Date: 2019-12
• Subjects: Ag block -- Manganese oxides -- Formaldehyde -- Photothermal catalysis; Energy development -- Periodicals; Energy industries -- Periodicals; Power resources -- Periodicals; Energy policy -- Periodicals; Energy development; Energy industries; Energy policy; Power resources; Electronic journals; Periodicals; 621.042
• DOI: 10.1016/j.mtener.2019.100343
• Languages: English
• ISSNs: 2468-6069

Abstract

Abstract: Small-size particles are not necessarily more active than large blocks in terms of solar light-driven photothermal catalysis. In this work, Ag block exhibits higher activity than small-size Ag nanoparticles in facilitating photothermal removal of HCHO over manganese oxide (MO). In contrary to oxide state of Ag nanoparticle, metallic core and oxide-state shell assemble into biphasic Ag block (Ag@AgOx ), because the shell prevents further oxidation of inner metallic Ag. Owing to LSPR effect of metallic core, the activation and mobility of lattice oxygen within MO are enhanced, so the efficiency in utilizing solar energy and catalytic activity are improved. Among them, the catalyst of 5% Ag@MO with Ag/Mn molar ratio of 0.05 exhibits an optimized and considerable activity in catalytically cleaning HCHO under irradiation of solar light even with light intensity of 25 mW/cm 2, which makes it possible to work under exposure of nature solar light. Meanwhile, the catalyst exhibits a remarkable stability as well as tolerance to humidity. Graphical abstract: Image 1 Highlights: Efficient utilization of renewable solar energy to photothermal oxidation of HCHO is realized by Ag@MO. It is the first finding that Ag species with different valence states assemble into heterostructure (Ag@AgOx ) in Ag blocks. The biphasic structure of Ag block can facilitate activation and mobility of lattice oxygen of MO via LSPR effect. 5% Ag@MO exhibits an optimized and considerable activity under weak solar light (c.a. 25 mW/cm 2 ) even at natural condition.