Preparation Of Sb₂S₃ Sensitized TiO₂ Nanorod Array Solar Cells And The Photovoltaic Performance Of The Corresponding Solar Cells

Antimony sulfide is a promising absorber layer material for solar cells because of its simple chemical composition,low phase formation temperature,earth-abundant constituent,and the Sb₂S₃ solar cells have the high absorption coefficient（in ultraviolet-visible region）and good storage stability.In order to clarify the influence of the preparation method,microstructure and surface interfacial modification of Sb₂S₃sensitized Ti O₂ nanorod array solar cells on the interfacial charge separation composite process and photovoltaic performance of the corresponding solar cells.In this dissertation,the influence of the Sb₂S₃ sensitized Ti O₂ nanorod array preparation,the Ti O₂ nanorod array microstructure adjusting,the surface modification,Cd S interlayer introducing and the spiro-OMe TAD:P3HT hybrid hole transporting material utilizing on the charge transport,separation and photovoltaic performance of the corresponding Sb₂S₃ sensitized Ti O₂ nanorod array solar cells is systematically investigated.The main contents are as follows:（1）The Sb₂S₃ sensitized Ti O₂ nanorod arrays are successfully prepared by spin coating assisted successive ionic layer adsorption and reaction（spin-SILAR）method using Sb Cl₃ solution in methanol as the Sb source and the Na₂S solution in methanol/water（v/v,95/5）as the S source.The influence of the spin coating cycle times and annealing process on the crystalline phase,optical absorption of the resulting Sb₂S₃sensitized Ti O₂ nanorod array and photovoltaic performance of the corresponding solar cells is systematically investigated.When the spin coating cycle times is 30,the corresponding Sb₂S₃sensitized Ti O₂ nanorod array solar cells obtain the PCE of 3.76%.（2）The Sb₂S₃ sensitized Ti O₂ nanorod arrays are prepared by pyrolysis method using antimony-thiourea（Sb-Tu）complex solution in DMF as the precursor solution.The influence of the Sb-Tu complex concentration in the precursor solution on the microstructure,crystalline phase,optical absorption of the resulting Sb₂S₃ sensitized Ti O₂ nanorod array and photovoltaic performance of the corresponding solar cells is systematically investigated.The Sb₂S₃ sensitized Ti O₂ nanorod array solar cells obtain the PCE of 4.72%.And the influence of the surface modifier structure on the charge transporting,separation,recombination and photovoltaic performance of the corresponding Sb₂S₃ sensitized Ti O₂ nanorod array solar cells is also investigated.The results reveal that the functional groups in the surface modifiers for the improvement of the photovoltaic performance is the order of-COOH>-PO₃H₂>-SO₃Na and the optimal carbon chain length is 12 for carbon acids as surface modifiers.The PCE of Sb₂S₃ sensitized Ti O₂ nanorod array solar cells with C₁₁H₂₃COOH can improve to5.37%.（3）The ultra-thin,compact and full-coverage Cd S interlayers are successfully prepared on Ti O₂ nanorod arrays by the spin-SILAR method using 5 mmol·dm^-3Cd（NO₃）₂ solution in methanol as the Cd source and 5 mmol·dm^-3 Na₂S solution in methanol/water as the S source.The influence of the spin coating cycle times on the microstructure,crystalline phase,optical absorption of the Cd S interlayer and the charge separation,transport,recombination and photovoltaic performance of the corresponding Sb₂S₃ sensitized Ti O₂ nanorod array solar cells is systematically investigated.When the spin-coating cycle times is 5,the Cd S interfacial layer is ultra-thin,compact and full-coverage and the PCE of the corresponding Sb₂S₃ sensitized Ti O₂ nanorod array solar cells increase from 4.83%without Cd S interfacial layer to5.74%with Cd S interfacial layer.（4）Sb₂S₃ sensitized Ti O₂ nanorod arrays are prepared by pyrolysis method using the antimony-butyldithiocarbamate（Sb-BDCA）complex solution in ethanol as the precursor solution.The influence of the mole ratio of Sb and BDCA in the precursor solution on the crystalline phase,optical absorption,microstructure of the resulting Sb₂S₃ sensitized Ti O₂ nanorod arrays and the charge separation,transport,recombination and photovoltaic performance of the corresponding solar cells is systematically investigated.When the mole ratio of Sb and BDCA in the precursor solution is 1:8,the resulting Sb₂S₃ thin films exhibit a preferred orientation of（211）and the corresponding Sb₂S₃ sensitized Ti O₂ nanorod array solar cells achieve the PCE of5.43%,and the PCE improve to 5.77%with C₁₁H₂₃COOH modification.（5）The Ti O₂ nanorod arrays with various microstructures are successfully prepared on the FTO/Ti O₂ compact layer substrate using hydrothermal methods.The Sb₂S₃sensitized Ti O₂ nanorod array solar cells are fabricated by pyrolysis using Sb-BDCA complex solutions as the precursor solution.The influence of the Ti O₂ nanorod array microstructure adjusting,the Cd S interlayer introducing,the spiro-OMe TAD:P3HT hybrid hole transporting material utilizing on the charge transporting,separation,and photovoltaic performance of the corresponding Sb₂S₃ sensitized Ti O₂ nanorod array solar cells is systematically investigated.The thermodynamics and kinetics process of the Ti O₂ nanorod array growth can be easily controlled by changing the titanium isopropoxide concentration in the hydrothermal growth solution and the hydrothermal growth time to obtain Ti O₂ nanorod arrays with various microstructures.The corresponding Sb₂S₃ sensitized Ti O₂ nanorod array solar cells obtain the optimal PCE of 5.74%,the PCE can increase to 6.32%by introducing an ultra-thin and compact Cd S interlayer,and further increase to 6.72%by using the spiro-OMe TAD:P3HT hybrid hole transport layer.