2,3-Dipentyldithieno[3,2-f:2',3'-h]quinoxaline-Based Organic Dyes for Efficient Dye-Sensitized Solar Cells: Effect of π-Bridges and Electron Donors on Solar Cell Performance.
Five novel metal-free organic dyes DQ1-5 containing a dipentyldithieno[3,2-f:2',3'-h]quinoxaline (DPQ) unit were synthesized and applied in dye-sensitized solar cells (DSSCs), where DPQ was employed as a π-spacer for the first time. Their photophysical, electrochemical, and theoretical calculations and photovoltaic properties were systematically investigated. All the five dyes show broad photoresponse. Especially the absorption edges of DQ3-5 extend to 800 nm on the TiO2 films. The inserted electron-rich unit 3,4-ethylenedioxythiophene or electron-withdrawing group benzothiadiazole (BTD) in DPQ-based dyes can greatly influence the optoelectronic properties of the dyes. In addition, the different electron donors also significantly affect the performance of the DSSCs. Under standard global AM 1.5 solar light conditions, the DQ5 sensitized solar cell obtained a power conversion efficiency of 7.12%. The result indicates that the rigid DPQ-based organic dye is a promising candidate for efficient DSSCs.
School of Chemistry and Chemical Engineering, State Key Laboratory of Luminescent Materials and Devices, South China University of Technology , Guangzhou 510641, China.
Zu-Sheng
ZS
Huang
School of Chemistry and Chemical Engineering, State Key Laboratory of Luminescent Materials and Devices, South China University of Technology , Guangzhou 510641, China.
Xu-Feng
XF
Zang
School of Chemistry and Chemical Engineering, State Key Laboratory of Luminescent Materials and Devices, South China University of Technology , Guangzhou 510641, China.
Tao
T
Hua
School of Chemistry and Chemical Engineering, State Key Laboratory of Luminescent Materials and Devices, South China University of Technology , Guangzhou 510641, China.
Lingyun
L
Wang
Institute of Organic Chemistry, University of Mainz , Mainz 55099, Germany.
Herbert
H
Meier
School of Chemistry and Chemical Engineering, State Key Laboratory of Luminescent Materials and Devices, South China University of Technology , Guangzhou 510641, China.
Derong
D
Cao
dipentyldithieno[3,2-f:2′,3′-h]quinoxaline; dye-sensitized solar cells; metal-free organic dyes; optoelectronic properties; photoresponse