Acta Phys. -Chim. Sin. ›› 2014, Vol. 30 ›› Issue (6): 1107-1112.doi: 10.3866/PKU.WHXB201404111

• ELECTROCHEMISTRY AND NEW ENERGY • Previous Articles     Next Articles

Synthesis of Mesoporous TiO2 Microspheres and Their Use as Scattering Layers in Quantum Dot Sensitized Solar Cells

BAI Shou-Li1, LU Wen-Hu1,2, LI Dian-Qing1, LI Xiao-Ning2, FANG Yan-Yan2, LIN Yuan2   

  1. 1 State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, P. R. China;
    2 Beijing National Laboratory for Molecular Sciences, Key Laboratory of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
  • Received:2014-02-27 Revised:2014-04-11 Published:2014-05-26
  • Contact: LI Dian-Qing, LIN Yuan E-mail:lidq@mail.buct.edu.cn;linyuan@iccas.ac.cn
  • Supported by:

    The project was supported by the National Key Basic Research Program of China (973) (2012CB932903).

Abstract:

Mesoporous TiO2 microspheres (MSs) were successfully synthesized by the direct hydrolysis of TiCl4 in ethanol aqueous solution using cetyltrimethyl ammonium bromide (CTAB) as a template. X-ray diffraction (XRD) revealed a rutile structure for TiO2 in all the products. Scanning electron microscopy (SEM) revealed that the TiO2 microspheres had an average diameter of 700 nm, and they were composed of packed nanoparticles that had a mean size of about 16 nm. Films with or without TiO2 microspheres, as a scattering layer on top of the TiO2 nanocrystalline layer, were prepared by the doctor-blade method. CdS/ CdSe quantum dots (QDs) were grown on films by chemical bath deposition (CBD) to form QD sensitized solar cells (QDSCs). Ultraviolet-visible and diffuse reflectance spectra showed that these micro-spherical structures were favorable for the deposition of QDs and a relatively higher light scattering effect was observed. This effectively enhanced light harvesting and led to an increase in the photocurrent of the QDSCs. As a result, a power conversion efficiency of 4.5% was obtained, which is 27.7% higher than that of QDSCs without scattering layers and 10.2% higher than that of QDSCs with traditional scattering layers composed of 20 and 400 nm TiO2 solid particles. We attribute this improvement to their higher light scattering effect and longer electron lifetimes.

Key words: Mesoporous TiO2 microsphere, Chemical bath deposition, CdS/CdSe quantum dot, Scattering layer

MSC2000: 

  • O646