Annealing effect on Sb2S3-TiO2 nanostructures for solar cell applications
1 School of Physics and State Key Laboratory of Crystal Materials, Shandong University, Jinan, 250100, People's Republic of China
2 School of Information Science and Engineering, Shandong University, Jinan, 250100, People's Republic of China
3 Department of Mechanical and Materials Engineering, Portland State University, P.O. Box 751, Portland, OR, 97207-0751, USA
4 Department of Physics, Portland State University, P.O. Box 751, Portland, OR, 97207-0751, USA
Nanoscale Research Letters 2013, 8:89 doi:10.1186/1556-276X-8-89Published: 19 February 2013
Nanostructures composited of vertical rutile TiO2 nanorod arrays and Sb2S3 nanoparticles were prepared on an F:SnO2 conductive glass by hydrothermal method and successive ionic layer adsorption and reaction method at low temperature. Sb2S3-sensitized TiO2 nanorod solar cells were assembled using the Sb2S3-TiO2 nanostructure as the photoanode and a polysulfide solution as an electrolyte. Annealing effects on the optical and photovoltaic properties of Sb2S3-TiO2 nanostructure were studied systematically. As the annealing temperatures increased, a regular red shift of the bandgap of Sb2S3 nanoparticles was observed, where the bandgap decreased from 2.25 to 1.73 eV. At the same time, the photovoltaic conversion efficiency for the nanostructured solar cells increased from 0.46% up to 1.47% as a consequence of the annealing effect. This improvement can be explained by considering the changes in the morphology, the crystalline quality, and the optical properties caused by the annealing treatment.