Nuket Parina, Kida Tetsuya, Vas-Umnuay Paravee
Center of Excellence in Particle and Material Processing Technology, Department of Chemical Engineering, Faculty of Engineering, Chulalongkorn University, Bangkok 10330, Thailand.
Division of Materials Science, Faculty of Advanced Science and Technology, Kumamoto University, Kumamoto 860-8555, Japan.
ACS Appl Mater Interfaces. 2024 Nov 27;16(47):65414-65424. doi: 10.1021/acsami.4c10039. Epub 2024 Oct 25.
Due to its exceptional optoelectronic properties in the visible spectrum, cesium lead bromide (CsPbBr) perovskite has attracted considerable attention in solar-driven organic transformations via photoelectrochemical (PEC) cells. However, the performance of the devices is adversely affected by electron-hole recombination occurring between a transparent conductive substrate, such as fluorine-doped tin dioxide (FTO), and a perovskite layer. Herein, to mitigate this issue, a compact layer of titanium dioxide (TiO) was employed as both an electron transport layer and a hole blocking layer to diminish charge recombination while facilitating electron transfer in such perovskite material. At the oxidation peak potential of 0.70 V vs Ag/AgNO, a hybrid photoanode of CsPbBr/TiO/FTO exhibited a significant increase in photocurrent density, from 15 to 41 μA/cm, compared to a configuration without a TiO layer. Furthermore, the introduction of methanol as a hole scavenger in the PEC system using the hybrid photoanode facilitated the separation of electron-hole pairs, which led to an enhanced photocurrent density of 60 μA/cm and promoted the production of formaldehyde. High-performance liquid chromatography (HPLC) confirmed the generation of formaldehyde at a concentration of 26.69 μM with a Faradaic efficiency of 92% under an applied potential of 0.50 V vs Ag/AgNO for 60 min of PEC reaction. In addition to the enhanced PEC performance achieved from this hybrid photoanode, CsPbBr nanocrystals (NCs) in this work were synthesized by the modified one-pot method under ambient air, where highly uniform and high-purity NCs were obtained. This work signifies the groundbreaking exploration of CsPbBr NCs with TiO as a photoelectrode material in the organic-based PEC cells, which efficiently improved the interfacial charge transfer within the photoanode for the conversion of methanol to formaldehyde, marking a significant advancement in the field.
由于溴化铯铅（CsPbBr）钙钛矿在可见光谱中具有优异的光电特性，其在通过光电化学（PEC）电池进行的太阳能驱动有机转化中受到了广泛关注。然而，诸如氟掺杂二氧化锡（FTO）等透明导电基底与钙钛矿层之间发生的电子 - 空穴复合对器件性能产生了不利影响。在此，为缓解这一问题，采用了一层致密的二氧化钛（TiO）作为电子传输层和空穴阻挡层，以减少电荷复合，同时促进此类钙钛矿材料中的电子转移。在相对于Ag/AgNO的氧化峰电位为0.70 V时，与没有TiO层的结构相比，CsPbBr/TiO/FTO混合光阳极的光电流密度显著增加，从15 μA/cm²增至41 μA/cm²。此外，在使用该混合光阳极的PEC系统中引入甲醇作为空穴清除剂，促进了电子 - 空穴对的分离，这导致光电流密度提高至60 μA/cm²，并促进了甲醛的生成。高效液相色谱（HPLC）证实，在相对于Ag/AgNO施加0.50 V电位进行60分钟的PEC反应后，生成了浓度为26.69 μM的甲醛，法拉第效率为92%。除了这种混合光阳极实现的PEC性能增强外，本工作中的CsPbBr纳米晶体（NCs）是在环境空气中通过改进的一锅法合成的，获得了高度均匀且高纯度的NCs。这项工作标志着以TiO作为光电极材料的CsPbBr NCs在有机基PEC电池中的开创性探索，其有效改善了光阳极内的界面电荷转移，用于将甲醇转化为甲醛，标志着该领域的重大进展。
