Theoretical insight into electronic structure and optoelectronic properties of heteroleptic Cu(I)-based complexes for dye-sensitized solar cells.
writer：S. X. Wei, K. Li, X. Q. Lu,* Z. G. Zhao, Y. Shao, Y. Dang, S. R. Li, W. Y. Guo.
keywords：Ab initio calculations; Electronic structure; Optical materials; Optical properties
source：期刊
specific source：Mater. Chem. Phys.
Issue time：2016年
A series of heteroleptic Cu(I)-based dyes were investigated by density functional theory (DFT) and time-dependent DFT (TD-DFT). Results showed that Cu(I)-based dyes were inclined to form distorted pseudo-trigonal pyramidal configurations with four-coordinated geometry index τ4 ranging from 0.905 to 0.914. The absorption spectra of Cu(I)-based dyes covered ～300.0–600.0 nm region, and the lowest excitation states were crucial for efficient electron excitation and separation. Suitable energy levels of Cu(I)-based dyes rendered them thermodynamically favorable for efficient electron injection into semiconductor and regeneration from electrolyte. Relative to π-conjugation, heteroaromatic groups introduced into ancillary ligands could significantly improve the property of Cu(I)-based dyes by decreasing HOMO-LUMO gaps, red-shifting spectral range, strengthening absorption intensity, boosting light-harvesting efficiency, and promoting interfacial electron injection. Specifically, Cu(I)-based dye with dithiole-functionalized group exhibited outstanding optoelectronic property.