Takeshita Tatsuya
Department of Applied Chemistry and Food Science, Fukui University of Technology, 3-6-1 Gakuen, Fukui 910-8505, Japan.
Nanomaterials (Basel). 2020 Oct 1;10(10):1958. doi: 10.3390/nano10101958.
The covalent attachment of photosensitizing dyes to TiO using silane coupling agents (SCAs) is a promising strategy for enhancing the photocatalytic activity of TiO-based photocatalysts and the photovoltaic conversion of dye-sensitized solar cells (DSSCs). This approach can control the geometry and orientation of the photosensitizing dye on the TiO surface. In this study, a density functional theory (DFT) and time-dependent DFT (TD-DFT) investigation was carried out on cresyl violet (CV) covalently attached to SCAs with a terminal oxirane group (OTES-Cn) to reveal the influence of OTES-Cn on the geometry of the photosensitizing dyes. The potential of CV covalently attached to OTES-Cn (CV-OTES-Cn) to act as a photosensitizing dye was also analyzed. The hydroxyl group formed by the epoxy-opening reaction between CV and OTES-Cn strongly influenced the geometry of CV-OTES-Cn, which was attributed to a CH-O interaction. Additionally, TD-DFT, frontier molecular orbital and molecular electrostatic potential calculations revealed that CV-OTES-Cn has excellent optical properties and electron injection ability. In particular, the characteristics of the unbent conformation of CV-OTES-Cn are expected to contribute significantly to the photocurrent in TiO-based photocatalysts and DSSCs. These findings enhance the understanding of the covalent attachment strategy using SCAs and contribute to improving TiO-based photocatalysts and DSSCs.
使用硅烷偶联剂（SCA）将光敏染料共价连接到TiO上，是增强TiO基光催化剂的光催化活性以及染料敏化太阳能电池（DSSC）的光电转换的一种有前景的策略。这种方法可以控制光敏染料在TiO表面的几何形状和取向。在本研究中，对与带有末端环氧乙烷基团的SCA（OTES-Cn）共价连接的甲酚紫（CV）进行了密度泛函理论（DFT）和含时密度泛函理论（TD-DFT）研究，以揭示OTES-Cn对光敏染料几何形状的影响。还分析了与OTES-Cn共价连接的CV（CV-OTES-Cn）作为光敏染料的潜力。CV与OTES-Cn之间的环氧开环反应形成的羟基强烈影响了CV-OTES-Cn的几何形状，这归因于CH-O相互作用。此外，TD-DFT、前线分子轨道和分子静电势计算表明CV-OTES-Cn具有优异的光学性质和电子注入能力。特别是，CV-OTES-Cn的未弯曲构象的特性有望对TiO基光催化剂和DSSC中的光电流做出显著贡献。这些发现增进了对使用SCA的共价连接策略的理解，并有助于改进TiO基光催化剂和DSSC。
