MA3Bi2Br9/g-C3N4 0D/2D S型异质结用于选择性光催化氧化甲苯

doi:10.1016/j.actphy.2026.100258

摘要/Abstract

摘要：

由于sp³ C–H键的反应惰性，甲苯转化为高附加值的苯甲醛仍面临巨大挑战。本研究采用原位生长法精确构建了MA₃Bi₂Br₉/g-C₃N₄异质结，并采用O₂分子作为绿色氧化剂进行甲苯选择性氧化研究。能带结构分析和先进表征技术证实该异质结遵循S型机制，从而产生强氧化还原能力的光生电子-空穴对，并为生成关键活性氧物种·O₂^–提供强大驱动力。优化后的20%MA₃Bi₂Br₉/g-C₃N₄复合材料展现出优异的甲苯转化率和产物选择性，在4 h内达到27.4%的甲苯转化率和94.2%的苯甲醛选择性。本研究为未来开发新型异质结光催化剂用于碳氢化合物向高值化学品的转化提供了普适性策略。

关键词: 无铅钙钛矿, 甲苯氧化, g-C₃N₄纳米片, S型异质结

Abstract:

Toluene to high-value benzaldehyde conversion remains a great challenge due to the reactive inertness of sp³ C–H bonds. Herein, MA₃Bi₂Br₉/g-C₃N₄ heterojunction was precisely fabricated by employing an in situ growth approach, and O₂ molecule was used as the green oxidant. Band structure analysis and advanced characterizations demonstrate the S-scheme mechanism working on the MA₃Bi₂Br₉/g-C₃N₄ heterojunction, thus enabling the powerful photogenerated electron/holes pairs and large driven force for generating ·O₂^– species, a critical reactive oxygen species in selective oxidation of toluene. The optimized 20%MA₃Bi₂Br₉/g-C₃N₄ displays enhanced toluene conversion and product selectivity, reaching 27.4% conversion and 94.2% benzaldehyde selectivity within 4 h. This study provides a universal strategy for future exploration of novel heterojunctions capable of high photocatalytic performance in converting hydrocarbons to high-value chemicals.

Key words: Lead-free perovskite, Toluene oxidation, g-C₃N₄ nanosheets, S-scheme heterojunction

陈丽珊, 李雪梅, 徐向菊, 董幼青, 徐全龙. MA₃Bi₂Br₉/g-C₃N₄ 0D/2D S型异质结用于选择性光催化氧化甲苯[J]. 物理化学学报, 2026, 42(9), 100258. doi: 10.1016/j.actphy.2026.100258

Lishan Chen, Xuemei Li, Xiangju Xu, Youqing Dong, Quanlong Xu. MA₃Bi₂Br₉/g-C₃N₄ 0D/2D S-scheme heterojunction for selective photooxidation of toluene[J]. Acta Phys. -Chim. Sin. 2026, 42(9), 100258. doi: 10.1016/j.actphy.2026.100258

链接本文: https://www.whxb.pku.edu.cn/CN/10.1016/j.actphy.2026.100258

https://www.whxb.pku.edu.cn/CN/Y2026/V42/I9/100258

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Entry ^(a)	Photocatalyst	Conversion (%)	Selectivity (%)
Entry ^(a)	Photocatalyst	Conversion (%)	BAD	BA	BAC
1	MA₃Bi₂Br₉	12.3	77.6	15.2	6.5
2	10%MA₃Bi₂Br₉/g-C₃N₄	29.7	85.3	12.1	2.5
3	20%MA₃Bi₂Br₉/g-C₃N₄	27.4	94.2	3.3	0.6
4	30%MA₃Bi₂Br₉/g-C₃N₄	25.2	90.0	9.6	0.3
5	g-C₃N₄	21.0	19.4	7.4	0.6
6 ^(b)	20%MA₃Bi₂Br₉/g-C₃N₄	4.8	89.5	3.2	2.4
7 ^(c)	20%MA₃Bi₂Br₉/g-C₃N₄	–	–	–	–
8	none	–	–	–	–

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MA₃Bi₂Br₉/g-C₃N₄ 0D/2D S型异质结用于选择性光催化氧化甲苯

MA₃Bi₂Br₉/g-C₃N₄ 0D/2D S-scheme heterojunction for selective photooxidation of toluene

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