Study On Hybrid Solar Cells Based On Dendritic TiO₂ Ordered Arrays

In the interest of providing multiple electron transport channels and increasing the load of narrow gap semiconductors and organic semiconductors,dendritic TiO₂ assembled by nanotubes and nanowires was fabricated on fluorine-doped transparent conductive glass?FTO?substrates with one-step hydrothermal method.Either chemical bath deposition?CBD?method or spin coating method was adopted to prepare Sb2S3 on dendritic TiO₂ arrays.And the hole transport material?HTM?was spin-coated on the dendritic TiO2/Sb2S3 composite structure to form TiO2/Sb2S3/HTM composite films.Then,scanning electron microscopy?SEM?,X-ray diffraction?XRD?,transmission electron microscopy?TEM?,ultraviolet-visible diffuse reflectance spectroscopy,transient photocurrent,steady-state fluorescence spectroscopy,open-circuit voltage attenuation curve,electrochemical impedance spectroscopy?EIS?and J-V curve were used to characterize the optoelectronic properties of the electrodes based on dendritic TiO₂.Specific research contents were as follows:1)Arrays of TiO₂ dendritic structure were constructed on FTO substrate by one-step hydrothermal method with titanium potassium oxalate as titanium source.The morphology,crystal type and photoelectric properties of dendritic TiO₂ were further studied.2)Sb₂S₃ nanoparticles were deposited on dendritic TiO₂ with CBD method.The effect of deposition time on the photoelectric properties was explored.Finally,hybrid solar cells?HSCs?assembled by dendritic TiO₂/Sb₂S₃ nanoparticles?3h?/P3HT/PEDOT:PSS achieved a power conversion efficiency?PCE?of 1.10%.3)Sb2S3 nanocrystals were deposited on dendritic TiO2 with spin coating method.The effect of sulfur source on the performance of HSCs was investigated by controlling the ratio of SbCl3 to thiourea?SbCl3:TU?in the precursor solution.The HSCs assembled by dendritic TiO2/Sb2S3 nanocrystals/P3HT/PEDOT:PSS with SbCl3:TU=1:1.8 can achieve a PCE of 1.56%,which is 41.82%higher than that of HSC_TS?3h?PP.4)Sb₂S₃ nanorods were deposited on dendritic TiO₂ by spin coating method with methanol as solvent.As HTM,P3HT:Spiro-OMeTAD blending system designed innovatively exhibits better photoelectric properties than pure P3HT and pure Spiro-OMeTAD systems.The HSCs assembled by dendritic TiO₂/Sb₂S₃nanorods/P3HT:Spiro-OMeTAD composite films obtained a PCE of 1.53%,and the corresponding stability was investigated for one month.5)Sb₂S₃ nanorods were deposited on dendritic TiO₂ by spin coating method with dimethylformamide?DMF?as solvent.PCPDTBT was introduced into the P3HT:Spiro-OMeTAD blending system,and PCPDTBT:P3HT:Spiro-OMeTAD blending system as HTM was designed innovatively.The HSCs assembled by dendritic TiO₂/Sb₂S₃nanorods/PCPDTBT:P3HT:Spiro-OMeTAD composite film obtained a PCE up to 1.83%,which showed an increase?19.61%enhancement?versus that of HSC assembled by dendritic TiO₂/Sb₂S₃ nanorods/P3HT:Spiro-OMeTAD composite film,and the corresponding stability was studied in six days.