Synergistic photocatalytic CH4 conversion to C1 liquid products using Fe oxide species-modified g-C3N4. Issue 15 (30th June 2022)

• Record Type: Journal Article
• Authors: Dai, Yue; Ju, Tangtong; Tang, Hailong; Wang, Meiling; Ma, Yongqing; Wang, Min; Zheng, Ganhong; Sun, Xiao
• Is Part Of: Catalysis science & technology. Volume 12:Issue 15(2022)
• Page Start: 4917
• Page End: 4926
• Publication Date: 2022-06-30
• Subjects: Catalysis -- Periodicals; 541.395
• DOI: 10.1039/d2cy00779g
• Languages: English
• ISSNs: 2044-4753

Abstract

Abstract : A binary catalyst Fe-modified g-C3 N4 was synthesized for direct photocatalytic CH4 conversion into C1 liquid products. A high C1 product yield and C1 selectivity of 16.52 mol molFe −1 h −1 and 95.5% were obtained under optimal conditions. Abstract : CH4 direct conversion into high value liquid oxygenated products under mild experimental conditions is of great significance to solve both environmental and energy problems. Although great effort has been made, yield and selectivity of products remain challenging. Herein, a binary catalyst Fe species-modified g-C3 N4 (denoted Fe1 -g-C3 N4 ), was synthesized for direct photocatalytic CH4 conversion into C1 liquid oxygenated products near room temperature (30 °C) with H2 O2 as an oxidant. Under optimal experimental conditions, a high yield of C1 products of 16.52 mol molFe −1 h −1 (2.95 mmol gcat. −1 h −1 ) was obtained with a C1 product selectivity of 95.5% (HCHO + HCOOH selectivity of 62%). The highest C1 product yield could reach 42.68 mol molFe −1 if the reaction time was prolonged to 6 h, accompanied by a high HCHO + HCOOH selectivity and turnover number of 94% and 110, respectively. Furthermore, the Fe1 -g-C3 N4 catalyst presented good stability and reusability after 4 cycle runs with negligible changes in the C1 product yield and selectivity. The greatly improved photocatalytic performance due to both increased H2 O2 utilization and enhanced electron/hole separation efficiency was discussed. The possible radical reaction mechanism was studied by combining X-ray photoelectron spectroscopy (XPS), electron spin resonance (ESR), in situ Fourier transform infrared spectroscopy (FTIR), gas chromatography-mass spectrometry (GC-MS) and radical scavenger experiments.