Du Chenyu, Sheng Jianping, Zhong Fengyi, He Ye, Liu Huiyu, Sun Yanjuan, Dong Fan
School of Resources and Environment, University of Electronic Science and Technology of China, Chengdu 611731, China.
Research Center for Carbon-Neutral Environmental & Energy Technology, Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu 611731, China.
Proc Natl Acad Sci U S A. 2024 Feb 27;121(9):e2315956121. doi: 10.1073/pnas.2315956121. Epub 2024 Feb 20.
Photo-catalytic CO reduction with perovskite quantum dots (QDs) shows potential for solar energy storage, but it encounters challenges due to the intricate multi-electron photoreduction processes and thermodynamic and kinetic obstacles associated with them. This study aimed to improve photo-catalytic performance by addressing surface barriers and utilizing multiple-exciton generation in perovskite QDs. A facile surface engineering method was employed, involving the grafting of ferrocene carboxylic acid (FCA) onto CsPbBr (CPB) QDs, to overcome limitations arising from restricted multiple-exciton dissociation and inefficient charge transfer dynamics. Kelvin Probe Force Microscopy and XPS spectral confirmed successfully creating an FCA-modulated microelectric field through the Cs active site, thus facilitating electron transfer, disrupting surface barrier energy, and promoting multi-exciton dissociations. Transient absorption spectroscopy showed enhanced charge transfer and reduced energy barriers, resulting in an impressive CO-to-CO conversion rate of 132.8 μmol g h with 96.5% selectivity. The CPB-FCA catalyst exhibited four-cycle reusability and 72 h of long-term stability, marking a significant nine-fold improvement compared to pristine CPB (14.4 μmol g h). These results provide insights into the influential role of FCA in regulating intramolecular charge transfer, enhancing multi-exciton dissociation, and improving CO photoreduction on CPB QDs. Furthermore, these findings offer valuable knowledge for controlling quantum-confined exciton dissociation to enhance CO photocatalysis.
用钙钛矿量子点（QDs）进行光催化CO还原显示出太阳能存储的潜力，但由于复杂的多电子光还原过程以及与之相关的热力学和动力学障碍，它面临着挑战。本研究旨在通过解决表面障碍并利用钙钛矿量子点中的多激子产生来提高光催化性能。采用了一种简便的表面工程方法，即将二茂铁羧酸（FCA）接枝到CsPbBr（CPB）量子点上，以克服因多激子解离受限和电荷转移动力学效率低下而产生的限制。开尔文探针力显微镜和XPS光谱证实，通过Cs活性位点成功创建了一个FCA调制的微电场，从而促进了电子转移，破坏了表面势垒能量，并促进了多激子解离。瞬态吸收光谱显示电荷转移增强，能垒降低，CO-to-CO转化率达到132.8 μmol g h，选择性为96.5%，令人印象深刻。CPB-FCA催化剂表现出四次循环可重复使用性和72小时的长期稳定性，与原始CPB（14.4 μmol g h）相比有显著的九倍提升。这些结果深入了解了FCA在调节分子内电荷转移、增强多激子解离以及改善CPB量子点上的CO光还原方面的影响作用。此外，这些发现为控制量子限制激子解离以增强CO光催化提供了宝贵的知识。
