Adhyaksa Gede Widia Pratama, Lee Ga In, Baek Se-Woong, Lee Jung-Yong, Kang Jeung Ku
1] Graduate School of EEWS (WCU), Department of Materials Science and Engineering, KAIST Institute for the NanoCentury, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 305-701, Republic of Korea [2].
Sci Rep. 2013;3:2711. doi: 10.1038/srep02711.
The efficiency of solar cells depends on absorption intensity of the photon collectors. Herein, mobile quantum dots (QDs) functionalized with thiol ligands in electrolyte are utilized into dye-sensitized solar cells. The QDs serve as mediators to receive and re-transmit energy to sensitized dyes, thus amplifying photon collection of sensitizing dyes in the visible range and enabling up-conversion of low-energy photons to higher-energy photons for dye absorption. The cell efficiency is boosted by dispersing QDs in electrolyte, thereby obviating the need for light scattering or plasmonic structures. Furthermore, optical spectroscopy and external quantum efficiency data reveal that resonance energy transfer due to the overlap between QD emission and dye absorption spectra becomes dominant when the QD bandgap is higher than the first excitonic peak of the dye, while co-sensitization resulting in a fast reduction of oxidized dyes is pronounced in the case of lower QD band gaps.
太阳能电池的效率取决于光子收集器的吸收强度。在此，将在电解质中用硫醇配体功能化的移动量子点（QDs）应用于染料敏化太阳能电池。量子点充当介质，接收能量并将其重新传输给敏化染料，从而增强敏化染料在可见光范围内的光子收集，并实现低能量光子到高能量光子的上转换以用于染料吸收。通过将量子点分散在电解质中提高了电池效率，从而无需光散射或等离子体结构。此外，光谱学和外部量子效率数据表明，当量子点带隙高于染料的第一个激子峰时，由于量子点发射光谱与染料吸收光谱的重叠而导致的共振能量转移占主导地位，而在量子点带隙较低的情况下，共敏化导致氧化染料快速还原的现象较为明显。
