Photocatalytic conversion of carbon dioxide (CO2) to carbon-based fuels is a promising approach to alleviating environmental and energy problems. Therefore, designing photocatalysts with morphological structures that favor gas–solid reactions and exhibit exceptional catalytic efficiencies is strongly demanded. In this work, a porous-framed heterostructure, constructed by anchoring Cs4PbBr6 perovskite nanocrystals on MnO2 hollow spheres, exhibits a 1.8-fold enhancement in the total electron consumption rate (95.3 μmol g–1 h–1) for CO2 photoreduction compared to the original Cs4PbBr6 nanocrystals. Detailed optoelectronic characterizations and theoretical calculations demonstrate that the electronic interactions in the heterointerface trigger disproportionation of Mn and help to expose active Mn sites that attract electrons, thus improving the CO2 activation and the following hydrogenation step to produce COOH*. The open and through porous structure also contributes to the enhanced reaction rate by accelerating mass transfer during the photoreduction reaction. This study provides valuable insights for the development of efficient catalysts for CO2 photoreduction in gas–solid reactions.
Sisi Li,Yajing Cai,Jiaying Situ,Biwen Wang,Beichen Ying,Jin He,Zhao-Qing Liu,Jianle Zhuang,Yibo Chen
Multi-mode responsive optical materials with versatile application prospects for optical sensing, optoelectrical devices, and information encryption are highly desired. Here we integrate fluorescent carbon dots onto the hollow MnO 2 spheres, and modulate the interaction between them to achieve a water-stimulated responsive system with dual-mode dynamic signals in both fluorescence and structural color. The composite film shows a structural color shifting from blue to green as well as displays a fluorescence “on” in the presence of trace water, with both changes capable of being reversibly switched up to 10 times. The amide bond between the two components enables the controllable dispersion and aggregation of the carbon dots which is essential to the reversibility. Fabrication of several security labels with separate information in structural color and fluorescence channels demonstrates the application potential of the composite. This work provides a concise route to develop new multi-mode responsive optical materials for applications in anti-counterfeiting, sensing, and coding.
危险品化学品经营许可证（带存储）