H 2 O 2 Photosynthesis from H 2 O and O 2 under Weak Light by Carbon Nitrides with the Piezoelectric Effect

作者：Jin Ma, Peng Cheng, Xiaoxiao Peng, Sicheng Liang, Zhixin Zhou, Kaiqing Wu, Ran Chen, Songqin Liu, Yanfei Shen, Haibo Ma, Yuanjian Zhang · 发表于：Journal of the American Chemical Society · 年份：2024 · DOI：10.1021/jacs.4c07170 · 被引用次数：117 · 研究领域：Gas Sensing Nanomaterials and Sensors、Advanced Photocatalysis Techniques、Nanoplatforms for cancer theranostics

Driven by the essential need of a green, safe, and low-cost approach to producing H 2 O 2, a highly valuable multifunctional chemical, artificial photosynthesis emerges as a promising avenue. However, current catalyst systems remain challenging, due to the need of high-density sunlight, poor selectivity and activity, or/and unfavorable thermodynamics. Here, we reported that an indirect 2e – water oxidation reaction (WOR) in photocatalytic H 2 O 2 production was unusually activated by C 5 N 2 with piezoelectric effects. Interestingly, under ultrasonication, C 5 N 2 exhibited an overall H 2 O 2 photosynthesis rate of 918.4 μM/h and an exceptionally high solar-to-chemical conversion efficiency of 2.6% after calibration under weak light (0.1 sun). Mechanism studies showed that the piezoelectric effect of carbon nitride overcame the high uphill thermodynamics of *OH intermediate generation, which enabled a new pathway for 2e – WOR, the kinetic limiting step in the overall H 2 O 2 production from H 2 O and O 2 . Benefiting from the outstanding sonication-assisted photocatalytic H 2 O 2 generation under weak light, the concept was further successfully adapted to biomedical applications in efficient sono-photochemodynamic therapy for cancer treatment and water purification.