Fabrication of the protonated pentatitanate nanobelts sensitized with CuInS2 quantum dots for photovoltaic applications

摘要

Titanate nanomaterials are considered to be the desirable materials for solar cells application because of their special optical absorption properties. In the present paper, protonated pentatitanate nanobelts prepared by hydrothermal method are used as photoanodes by screen-printing method. While CuInS2 quantum dots with the particle size of 3.5 nm are synthesized by solvothermal method and uniformly linked on the surface of the protonated pentatitanate nanobelt films by 3-Mercaptopropionic acid, which serves as the sensitizers in sensitized solar cells. The sensitization content of the quantum dots on the photoan-ode is determined by the number of preparative chemical linking cycles. The optical absorption of such sensitized pentatitanate nanobelt films enhances under the full solar spectrum, following with a red-shift of the absorption peak from 308 nm to 325 nm. Under AM 1.5 illumination, the best photovoltaic conversion efficiency of these structures using a sulfide/polysulfide redox electrolyte is about 1.05% following 8 preparative chemical linking cycles, which is better than that of TiO2 nanocrystalline photoanodes. This result suggests that these photoanodes may have the significant research prospects and potential application in solar cells.