Regioisomeric quinoxaline-based dyes (NQXs) were synthesized to study the effect of substitution patterns on the performance of quinoxaline-based dye sensitized solar cells (DSSCs). The 1 H NMR results indicated that the substitution patterns of ethylene groups on the quinoxaline unit greatly affect the molecular architecture through C–H⋯N hydrogen bonding, which also influenced the absorption and efficiency of the DSSCs. The highest occupied molecular orbital (HOMO) levels of the NQXs were estimated to range from 0.94 to 0.99 V by cyclic voltammetry and visible absorption studies, which is suitable for DSSCs. The photocurrent density-voltage curves and incident photon-to-electron conversion efficiency spectra of NQXs indicated that the introduction of phenothiazine groups at the 2- and 3-positions of quinoxaline is the most effective pattern for quinoxaline-based organic sensitizers in DSSCs.
Bibliographical noteFunding Information:
This work was supported by the Technology Innovation Program and the New and Renewable Energy Core Technology Program of the Korea Institute of Energy Technology Evaluation and Planning (KETEP) , and the granted financial resources from the Ministry of Trade, Industry and Energy, Republic of Korea (No. 10047756 and No. 20163030013960 ) The authors would also like to thank Prof. Sung Hoon Jeong (Smart Organic Materials Laboratory, Hanyang University, Korea) and Prof. Min Jae Ko (Advanced Energy Materials Laboratory, Hanyang University, Korea) for allowing us to use their equipment related to cell fabrication, solar simulators, EQE measurements, and EIS measurements.
All Science Journal Classification (ASJC) codes
- Chemical Engineering(all)