Suppression of Recombination in PbS and PbSe Based Quantum Dot Solar Cells by Surface and Interface Engineering
Feng Liu a, Yang Zhang a, Chao Ding a, Yaohong Zhang a, Qing Shen a d, Taro Toyoda a d, Guohua Wu b, Joe Otsuki b, Yuhei Ogomi c, Shuzi Hayase c d
a The University of Electro-Communications, 1-5-1 Chofugaoka, Chofu, Tokyo, 182, Japan
b Nihon University, 1-8-14 Kanda Surugadai, Tokyo, 101
c Kyushu Institute of Technology, 204 Hibikino Wakamatsu-ku, Kitakyushu - Fukuoka, 808, Japan
d Crest, Japan Science and Technology Agency, 4-1-8 Honcho, Kawaguchi, Saitama, 332-0012, Japan
Asia-Pacific International Conference on Perovskite, Organic Photovoltaics and Optoelectronics
Proceedings of International Conference Asia-Pacific Hybrid and Organic Photovoltaics (AP-HOPV17)
Yokohama-shi, Japan, 2017 February 2nd - 4th
Organizers: Tsutomu Miyasaka and Iván Mora-Seró
Oral, Yaohong Zhang, presentation 111
Publication date: 7th November 2016

Compared with conventional solar cells, quantum dot solar cells (QDSCs) are easier to prepare with low fabrication cost. Additionally, QDs present high extinction coefficients, tunable absorption spectra, and multiple exciton generation (MEG) effect. PbS and PbSe QDs have attracted attention due to their small bulk bandgap, high dielectric constant, and large exciton Bohr radius. However, due to the QDs have large surface area, there are more surface defects on QDs than that of their bulk materials. So the charge carrier recombination at QDs’ surface have a decisive impact on the QDSCs performance. What’s more, the interface recombination also plays an important part to affect the property of the QDSCs. Therefore, reducing and inhibiting the surface and interface recombination in QDSCs are an effective way to improve the performance of PbS and PbSe based QDSCs. Here, we modified the PbSe QDs surface by using halide ion ligands. After modification, the air stability of PbSe QDs and QDSCs treated by halide ion ligands were enhanced than short organic ligands, and the QDSCs treated by I- obtained the best performance. In order to inhibit the interface recombination at PbS QDs/Au, we introduced organic small molecules as hole transport materials (HTMs) at PbS/Au interface. We found that the device with HTMs obtained higher open circuit voltage (Voc) and larger fill factor (FF) than the devices which without using HTMs. The results of open-circuit transient voltage decay and electrochemical impedance spectroscopy measurements indicated that there is less interface recombination in the devices with HTMs than those devices without using the HTMs.

© Fundació Scito
We use our own and third party cookies for analysing and measuring usage of our website to improve our services. If you continue browsing, we consider accepting its use. You can check our Cookies Policy in which you will also find how to configure your web browser for the use of cookies. More info