Acta Phys. -Chim. Sin. ›› 2015, Vol. 31 ›› Issue (7): 1331-1337.doi: 10.3866/PKU.WHXB201505072

• ELECTROCHEMISTRY AND NEW ENERGY • Previous Articles     Next Articles

CuInS2 Quantum Dot-Sensitized Solar Cells Fabricated via a Linker-Assisted Adsorption Approach

WANG Nan1,2, LIANG Zhu-Rong2,3, WANG Xin1,2, XU Xue-Qing2,3, FANG Jun1, WANG Jun-Xia2,3, GUO Hua-Fang2,3   

  1. 1 Department of Chemical & Biochemical Engineering, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, Fujian Province, P. R. China;
    2 Renewable Energy and Gas Hydrate Key Laboratory of Chinese Academy of Sciences, Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, P. R. China;
    3 University of Chinese Academy of Sciences, Beijing 100049, P. R. China
  • Received:2015-04-13 Revised:2015-05-07 Published:2015-07-08
  • Contact: XU Xue-Qing, FANG Jun E-mail:Xuxq@ms.giec.ac.cn;jfang@xmu.edu.cn
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (21073193, 21273241, 21376195), Project on the Integration of Industry, Education and Research of Guangdong Province, China (2012B091100476), and Science and Technology Research Project of Guangzhou, China (2014J4100218).

Abstract:

Colloidal chalcopyrite CuInS2 (CIS) quantum dots (QDs) were synthesized using copper(I) iodine (CuI) and indium(III) acetate (InAc3) as metal cationic precursors, and dodecanethiol (DDT) as the sulfur source and solvent. The microstructure and optical properties of the prepared CIS QDs were characterized by X-ray diffraction (XRD), Raman spectroscopy, high-resolution transmission electron microscopy (HRTEM), and UVVis absorption spectroscopy. The results showed that the CIS consisted of chalcopyrite phase and exhibited Cu-Au ordering. With prolonged reaction time, the grain sizes of the QDs became larger and the absorption edges of the CIS QDs showed a red-shift owing to the size-induced quantum confinement effect. For the first time, DDT-capped CIS QDs with narrow size distribution were connected to the inner surface of mesoporous TiO2 films via a thioglycolic acid (TGA)-assisted adsorption approach, which was simple and easy to carry out. The adsorption behaviors of both TGA and the CIS QDs on the TiO2 films were detected by attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy. The results indicated that TGA was adsorbed onto the surface of TiO2 via COOH groups while the ―SH group was exposed outside, and replaced DDT at the surface of the CIS QDs, leading to the attachment between TiO2 and CIS. It was revealed that the CIS QDs of ~3.6 nm in size exhibited the best light absorption capacity and photovoltaic performance. An over-coating of CdS significantly improved the performance of the QDS

Key words: CuInS2, Quantum dot, Sensitized solar cell, Bifunctional linker, Thioglycolic acid, Assisted adsorption