Alizarin‐TiO2 LMCT Complex with Oxygen Vacancies: An Efficient Visible Light Photocatalyst for Cr(VI) Reduction. Issue 11 (21st August 2020)

• Record Type: Journal Article
• Authors: Li, Meichen; Li, Yaru; Zhao, Jingyu; Li, Mingcheng; Wu, Yongchuan; Na, Ping
• Is Part Of: Chinese journal of chemistry. Volume 38:Issue 11(2020)
• Page Start: 1332
• Page End: 1338
• Publication Date: 2020-08-21
• Subjects: Photocatalysis -- Dyes -- Ligand effects -- Organic‐inorganic hybrid composites -- Chromium; Chemistry -- Periodicals; 540.5
• DOI: 10.1002/cjoc.202000080
• Languages: English
• ISSNs: 1001-604X

Abstract

Summary of main observation and conclusion: The AL‐P25 composites (AL = alizarin, P25 = nano titanium dioxide) with oxygen vacancies were synthesized by a simple hydrothermal method and applied for the photoreduction of Cr(VI) under visible light. The AL‐P25 composites were characterized by scanning electron microscopy, X‐ray diffraction, X‐ray photoelectron spectroscopy analysis, Fourier transform infrared spectrometer, thermo‐gravimetric analysis, UV–vis diffuse reflectance spectroscopy, photoluminescence spectroscopy and electron paramagnetic resonance spectroscopy. The results suggested that the AL‐P25 composites were successfully prepared, and alizarin was linked to P25 via Ti—O—C bonds. AL‐P25 composites represented excellent photoreduction efficiency on Cr(VI) under visible light, which was 99.4% after 60 min of illumination. Finally, a photocatalytic mechanism of AL‐P25 composites was proposed that ligand‐metal charge transfer (LMCT) process between alizarin and P25 effectively enhances separation efficiency of photogenerated electrons and holes. Abstract : An alizarin‐TiO2 LMCT complex with oxygen vacancies was designed and fabricated, and achieved a Cr(VI) removal efficiency of 99.4%, owing to favorable role of LMCT sensitization process.