Modulation of Excitonic Confinement of TiO2 in Molten Salts for Overall CO2 Photoreduction. Issue 10 (22nd March 2023)

• Record Type: Journal Article
• Authors: Wang, Jing; Sheng, Ren; Gu, Dong; Peng, Yuhao; Xiao, Juanxiu; Shen, Yijun; Xiao, Wei
• Is Part Of: Chinese journal of chemistry. Volume 41:Issue 10(2023)
• Page Start: 1185
• Page End: 1190
• Publication Date: 2023-03-22
• Subjects: Molten salt -- CO2 reduction -- Photocatalysis -- Excitonic confinement -- Charge transfer; Chemistry -- Periodicals; 540.5
• DOI: 10.1002/cjoc.202200680
• Languages: English
• ISSNs: 1001-604X

Abstract

Comprehensive Summary: Excitonic confinement greatly determines the charge carrier transport of photocatalysts. A molten salt modulation of excitonic confinement is herein demonstrated as formation of ultrafine carbon‐doped anatase TiO2 with grafted graphitic carbon nitride, which is rationalized as an excellent catalyst for overall CO2 photoreduction. Compared with bulk TiO2, the carbon‐doped TiO2 (M‐TiO2 ) possesses a weaker excitonic confinement to decrease exciton binding energy from 99 to 58 meV, consequently enhancing free‐charge‐carrier generation and transportation. Effective Z‐scheme electron transfer from M‐TiO2 to C3 N4 is built, enhancing the CO2 conversion via the synchronous optimization of redox ability, CO2 activation, and *COOH generation. This work highlights the unique chemistry of excitonic dissociation on facilitating separation of electron and hole, and also extends the scope of molten salt‐mediated modulation of photocatalysis materials. Abstract : A molten salt modulation of excitonic confinement is employed to generate ultrafine carbon‐doped anatase TiO2 with grafted graphitic carbon nitride. The doped C atom in the TiO2 promotes dissociation of excitons into electrons and holes, and enhances visible light absorption. The construction of Z‐scheme M‐TiO2 ‐C3 N4 heterojunction improves the overall CO2 photoreduction perforemance via the synchronous optimization of redox ability, CO2 activation, and *COOH generation.