Fan Yang, Li Hua-Min, Duan Rui-Huan, Lu Hai-Ting, Cao Jun-Tao, Zou Guo-Dong, Jing Qiang-Shan
Henan Province Key Laboratory of Utilization of Non-metallic Mineral in the South of Henan, College of Chemistry and Chemical Engineering, Xinyang Normal University , Xinyang 464000, China.
Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences , Fuzhou 350002, China.
Inorg Chem. 2017 Nov 6;56(21):12775-12782. doi: 10.1021/acs.inorgchem.7b01527.
The metal-to-core charge transfer (MCCT) transition in sensitized titanium-oxo clusters is an important process for photoinduced electron injection in photovoltaic conversion. This process resembles most closely the Type II photoinjection in dye-sensitized solar cells. Herein we report the synthesis and photophysical and photoelectrochemical (PEC) properties of the phosphonate-stabilized titanium-oxo clusters containing the ferrocenecarboxylate ligands. These ferrocene-containing clusters exhibit intense visible absorption extended up to 600 nm along with low optical band gaps of ∼2.2 eV. The low-energy transitions of these clusters were systematically investigated by UV-vis spectroscopy and DFT/TDDFT calculations. The combined experimental and computational studies suggest that the ferrocenecarboxylate-substituted titanium-oxo clusters form a donor-acceptor (D-A) system. The low-energy transition of these clusters primarily involves the MCCT from the iron center to TiO cluster core. The TiO core structure and phosphonate ligands both have great influence on the PEC properties of the clusters. This work provides valuable examples for the sensitized titanium-oxo clusters in which electron injection takes place via MCCT transition.
敏化钛氧簇中的金属到核心电荷转移（MCCT）跃迁是光伏转换中光致电子注入的重要过程。该过程与染料敏化太阳能电池中的II型光注入最为相似。在此，我们报道了含有二茂铁羧酸酯配体的膦酸酯稳定化钛氧簇的合成及其光物理和光电化学（PEC）性质。这些含二茂铁的簇表现出强烈的可见光吸收，延伸至600 nm，同时具有约2.2 eV的低光学带隙。通过紫外可见光谱和DFT/TDDFT计算系统地研究了这些簇的低能跃迁。实验和计算相结合的研究表明，二茂铁羧酸酯取代的钛氧簇形成了供体-受体（D-A）体系。这些簇的低能跃迁主要涉及从铁中心到TiO簇核心的MCCT。TiO核心结构和膦酸酯配体都对簇的PEC性质有很大影响。这项工作为通过MCCT跃迁进行电子注入的敏化钛氧簇提供了有价值的实例。
