Enhanced Visible-Light Photocatalytic Activity of Ag QDs Anchored on CeO₂ Nanosheets with a Carbon Coating

• Main Authors: Xiaogang Zheng, Qian Chen, Sihao Lv, Xiaojin Fu, Jing Wen, Xinhui Liu
• Format: Article
• Language: English
• Published: MDPI AG 2019-11-01
• Series: Nanomaterials
• Subjects: ag qds; ceo₂ nanosheets; carbon coating; photocatalytic activity; visible light
• Online Access: https://www.mdpi.com/2079-4991/9/11/1643

Ag quantum dots (QDs) anchored on CeO₂ nanosheets with a carbon coating (Ag/CeO₂@C) (composites) were prepared via an in situ reduction approach for the photocatalytic degradation of Cr(VI) and tetracycline hydrochloride (TCH) in the visible-light region. The photocatalytic activity of Ag/CeO₂@C was greatly affected by carbon content, Ag-doping content, Cr(VI) concentration, pH value, and inorganic ions. Enhanced photocatalytic activity was obtained by Ag/CeO₂@C (compared to CeO₂ and CeO₂@C), of which 3-Ag/CeO₂@C-2 with an Ag-doping content of 5.41% presented the best removal efficiency and the most superior stability after five cycles. <b>&#183;</b>O₂^&#8722; and <b>&#183;</b>OH radicals were crucial for the photocatalytic capacity of 3-Ag/CeO₂@C-2. The combined effect of the surface plasma resonance (SPR) of Ag QDs, an electron trapper of carbon shells, and the redox activity of the Ce(III)/Ce(IV) coupling induced efficient charge transfer and separation, suppressing the recombination of electron&#8722;hole pairs.