Integrated Nanotechnology Research Center, Department of Physics, Faculty of Science, Khon Kaen University, Khon Kaen 40002, Thailand.
J Mol Model. 2013 Mar;19(3):1407-15. doi: 10.1007/s00894-012-1692-9. Epub 2012 Dec 6.
Essential parameters related to the photoelectrochemical properties, such as ground state geometries, electronic structures, oxidation potential and electron driving force, of cochineal insect dyes were investigated by DFT and TDDFT at the B3LYP/6-31+G(d,p) level of the theory. The results show that the major charge flow dynamic for all dyes is the HOMO→LUMO transition. The bi-coordinated binding mode, in which the dye uses one carboxyl- and hydroxyl oxygen bound to Ti(IV), is found for all dye-TiO(2) systems. Additionally, the doubly bi-coordinated binding mode in which the dye used both carboxyl groups bound to two Ti(IV) is also possible due to high energy distribution occupied at anchoring groups. This study highlights that most of these insect dyes can be good photosensitizers in dye-sensitized solar cells based on their strong binding to the TiO(2) surface, good computed excited state oxidation potential and thermodynamically favored electron driving force.
通过密度泛函理论（DFT）和时间域密度泛函理论（TDDFT）在 B3LYP/6-31+G(d,p)理论水平上，研究了胭脂虫虫染料的光电化学性质相关的基本参数，如基态几何形状、电子结构、氧化电位和电子驱动力。结果表明，所有染料的主要电荷流动动态都是 HOMO→LUMO 跃迁。对于所有染料-TiO2 体系，发现染料采用一个羧基和一个羟基氧与 Ti(IV)配位的双配位结合模式。此外，由于占据了高能分布的位置，染料也可以采用双配位结合模式，其中两个羧基与两个 Ti(IV)配位。这项研究表明，由于这些昆虫染料与 TiO2 表面具有很强的结合能力、良好的计算激发态氧化电位和热力学上有利的电子驱动力，它们大多数都可以成为染料敏化太阳能电池中的良好光敏剂。
