The optical and electrochemical properties of CdS/CdSe co-sensitized TiO2 solar cells prepared by successive ionic layer adsorption and reaction processes

The optical and electrochemical properties of CdS/CdSe co-sensitized TiO2 solar cells prepared by successive ionic layer adsorption and reaction processes Original Research Article Pages 964-971 Yaohong Zhang, Jun Zhu, Xuechao Yu, Junfeng Wei, Linhua Hu, Songyuan Dai Close preview | Related articles | Related reference work articles Abstract | Figures/Tables | References Abstract Quantum dot sensitized nanocrystalline TiO2 solar cells (QDSSCs) are promising third-generation photovoltaic devices. A series of CdS/CdSe co-sensitized TiO2 photoanodes for QDSSCs were prepared by successive ionic layer adsorption and reaction (SILAR) processes. The growth of CdS and CdSe layers were monitored by taking UV–Visible absorption spectra and the SILAR cycles of CdS and CdSe show different impact on the performance of QDSSCs. With the deposition times of CdS increasing (from 4 to 7 cycles), the short-circuit current density of the device is enhanced. On the contrary, the increasing deposition times of CdSe (from 4 to 7 cycles) has a negative effect for the generation and collection of photoelectron. In addition, the electrochemical impedance spectroscopy technology was used to investigate the impedance of diffusion and recombination in the various devices. Moreover, the effect of SILAR cycles on the recombination resistance was discussed based on the electrochemical impedance spectroscopy results. Article Outline 1. Introduction 2. Experimental 2.1. Materials 2.2. Preparation of CdS/CdSe co-sensitized mesoporous TiO2 photoanode 2.3. Fabrication of QDSSCs 2.4. Measurements 3. Results and discussion 3.1. HR-TEM study of CdS and CdSe QDs on the TiO2 surface 3.2. Optical properties of CdS/CdSe co-sensitized TiO2 film 3.3. Photovoltaic performance of CdS/CdSe co-sensitized TiO2 film 3.4. Electrochemical impedance spectra of CdS/CdSe co-sensitized TiO2 solar cells 4. Conclusions Acknowledgements References