Study On Flexible ZnO Based Dye-Sensitized Solar Cells

Flexible dye-sensitized solar cells(DSSCs)have attracted much attention,because they are handy and are convenient for transportation.In particular,flexible DSSCs using thin and lightweight conducting plastic substrates for their photoelectrodes are cheap and they are suitable for roll-to-roll production.In this paper,electrochemical deposition method,chemical bath deposition method and blading-doctor method were employed to prepare flexible ZnO photoanode and dye sensitized solar cell.In electrochemical deposition method,the effect of the concentration of electrolyte,deposition potential and deposition temperature on the morphology of ZnO film and the performance of DSSC were mainly studied.In the chemical bath deposition method,the effect of the precipitators and the concentration of hexamethylenetetramine on the morphology of ZnO film and the performance of DSSC were mainly studied.In the blading-doctor method,the effect of Li+ doping ZnO on the morphology of ZnO and the performance of DSSC were mainly studied.The main experimental contents and results were as follow:(1)ZnO photoanode films were prepared by electrochemical deposition method.When the concentration of the electrolyte,deposition potential and deposition temperature were 0.10M,-0.85V and 60?,respectively,the spherical ZnO photoanode film was deposited on the ITO-PEN substrate.The Voc,Jsc,FF and PCE of the flexible DSSC assembled by the photoanode film were 0.54V,1.52mA·cm-2,0.44 and 0.37%,respectively.The performance of the DSSC improved after the film activated by ammonia,and the Voc,Jsc,FF and PCE of the DSSC were 0.62V,2.53mA·cm-2,0.56 and 0.88%,respectively.(2)Zinc acetate was used as precursor in the chemical bath deposition method.The effect of the precipitator such as HMT,ammonia and C2H8N2 on the morphology of ZnO film and the performance of DSSC were studied.When the precipitator was HMT,the PCE of the DSSC was optimum.The Voc,Jsc,FF and PCE of the DSSC were 0.60V,2.65mA·cm-2,0.70 and 0.81%,respectively.The four different concentration of HMT of 0.1M,0.2M,0.3M and 0.4M on the the morphology of ZnO and the performance of DSSCs were studied.When the concentration of HMT was 0.3M,the PCE of the DSSC was optimum.The Voc,Jsc,FF and PCE of the DSSC were 0.60V,2.65mA·cm-2,0.72 and 1.12%,respectively.(3)ZnO film were prepared by precipitation method,and Zn(NO3)2·6H2O and NaOH were used as raw materials.The effect of NaOH solution concentration on the ZnO morphology and the performance of DSSC were studied.When the concentration of NaOH solution was 0.4 0 M,the Voc,Jsc,FF and PCE of the DSSC were 0.60V,2.64mAcm-2,0.74 and 1.18%,respectively.Then,the Li-doping ZnO powders were prepared by the prepitation method,and the ZnO films were prepared by the blading-doctor method.Compared with the performance of no Li-doping DSSC,the performance of Li-doping DSSC was improved.The Voc,Jsc,FF and PCE of the DSSC were 0.64V,3.53mA·cm-2,0.63 and 1.18%,respectively.Finally,ammonia activation was an effective method to improve the performance of the flexible dye-sensitized solar cell.When the concentration of ammonia was 0.03M,and the reactive time was 10 min,the Voc,Jsc,FF,and PCE of the DSSC were 0.63V,4.11mA·cm-2,0.75 and 1.94%,respectively.