Modification Of Photoanode In Dye Sensitized Solar Cell

The dye sensitized solar cells(DSSCs) have attracted extensive research interests from the scientists of different fields all over the world since the DSSC was found in1991by Micheal.Gratzel. As the main component of DSSCs, the photoanodes were widely researched, because it would determine the efficiency of the DSSCs significantly. Recently, incorporation of foreign elements into the photoanode is becoming the research mainstream about photoanode modifications. In this work, the different graphene-like addiditions were incorporated into TiO2photoanode, aiming at enhancing the efficiency of DSSCs by experiments. The main contents are as follows.(1)The hydrothermal and sol-gel methods were adopted to prepare TiO2. Results indicate that the photo to current conversion efficiency(PCE) of TiO2DSSC by the hydrothermal method is double, compared to the TiO2DSSC obtained by the sol-gel method. Sequentially, the seed growth method was used to synthesize ZnO nanorods on the FTO glass. TiO2slurry was coated on the as-prepared ZnO film by doctor blade techniques to fabricate the hybrid photoanode. Compared to ZnO DSSC, the PCE of hybrid DSSC was increased by66%.(2)The modified Hummer method was used to prepare graphene oxide(GO) and the nitrogen-doped reduced grapheme oxide(N-rGO) was obtained by solvothermal method in ammonia atmosphere. By comparing the PCE of different amount of GO and N-rGO incorporated DSSCs, it is found that both GO and N-rGO can inhibit the charge recombination and increase the Voc and Jsc to some extent, and thus improve the PCE of the DSSCs.When the added amount was0.05mg, GO and N-rGO incorporated DSSCs reach their highest PCE at6.77%and7.19%, which gain an increament of5.78%and13.23%respectively, compared to unmodifed TiO2DSSCs. Obviously, N-rGO is an excellent additive for enhancing the PCE of DSSC.(3)The Covalent organic polymer-4(COP-4) were carbonized under Ar atmosphere at650℃and850℃to acquire650-COP-4and850-COP-4. By comparing the PCE of650-COP-4and850-COP-4incorporated DSSCs, it is found that both650-COP-4and850-COP-4can inhibit the charge recombination and increase the Voc, but decrease the Jsc. Unfortunately, the PCE of the COP-4-modified DSSCs decreases slightly in these cases studied. It still needs more investigations to find novel materials for enhancing the PCE of DSSCs.