Sunlight-driven photosynthesis by covalent organic frameworks (COFs) from water and air without using sacrificial reagents is a promising H2O2 fabrication approach, but is still restricted by the insufficient charge separation and sluggish 2e- water oxidation process. Herein, we provide a facile strategy to simultaneously improve charge separation and water oxidation in COFs via confining the charge transfer pathways from two diversion ones to a confluence one through regulating the site of nitrogen in bipyridine. Combining in-situ characterization with computational calculations, we reveal that compared to COF-BD1 containing two diversion charge transfer pathways, the charge transfer pathway in COF-BD2 is confined to a confluence one due to the electron-deficiency effect of nitrogen, which greatly accelerates the intermolecular and out-of-plane charge transfer. Via effectively reducing the energy barrier of rate-determining water oxidation reaction, the subsequent water oxidation process to produce key *OH intermediate in COF-BD2 is also greatly facilitated, boosting the yield of H2O2 (5211 μmol g-1 h-1) from water, oxygen, and light without sacrificial agents or additional energy consumption. We further demonstrate that H2O2 can be efficiently produced by COF-BD2 in broad pH range, in real water, and in enlarged reactor with using natural sunlight for water decontamination.
The successful adjustment of international students to the new environment depends on their ability to interact effectively with the external environment. However, the literature has not yet provided a clear understanding of how the support provided by host universities affects the academic achievement and cultural adaptation of international students, particularly in longitudinal studies involving students from different countries and regions in China. Based on Student-centered Learning Engagement framework, this study developed and tested a model composed of three variables—university support, academic achievement and cultural adaptation, and collected data from South Asian students at Chinese universities from 2017 to 2019 through questionnaires. The findings revealed that university support significantly affected cultural adaptation through academic achievement. The study suggests that Chinese universities should provide appropriate levels of support for international students to achieve positive academic outcomes, and to better understand and adapt to the universities, societies, and cultures.