Preparation Of Thin Film Electrodes Based On One-Dimensional Iron Oxide Semiconductor And Their Photoelectric Properties

Solar cell is one kind of effective methods of photoelectric conversion in solar energy utilization,semiconductor materials with photoelectric conversion performance have become a hot research topic in solar cells.?-Fe₂O₃,a common semiconductor material with a narrow band gap of 2.1 eV,has potential application in the solar cell due to its good chemical stability,low cost,capability to absorb photons in the visible range.Despite the hematite possesses such many advantages,it still has some shortcomings such as the short lifetime of photo-generated charge carriers,low electron mobility,and the actual photoconversion efficiency in existing reports is far below the theoretical efficiency.In order to overcome these issues,the construction of heterostructure and auxiliary doping are considered as commonly solutions to solve the problem.BiOI is regarded as a new generation of the semiconductor optical electrode material of highly efficient,environmental friendly,visible light response,which possess the advantages of high chemical stability,narrow band gap width.However,photogenerated charges in pure BiOI still have recombination probability in migration process,resulting in sharp drop of the photocatalytic efficiency and photoelectric conversion performance.In this work,the construction of heterostructure was applied to synthesize Fe₂O₃/BiOI photoanode and auxiliary micro-dopant was used to prepare Bi-doped Fe₂O₃ photoanode.The morphology,photoelectric conversion performance have been characterized.Moreover,the transmission mechanism of electrons and holes of photoproduction have been explored.The experimental work is mainly as follows:1.As a promising photoanode material for efficient photoelectric conversion in solar cells,Fe₂O₃/BiOI was fabricated with BiOI attached to a one-dimensional Fe₂O₃nanorod array.The two semiconductors of n-type Fe₂O₃ and p-type BiOI formed a n-p heterogeneous structure for the improving of efficient charge separation.In turn,the photoelectric conversion efficiency of solar cells was improved.The maximization of photoelectric conversion efficiency was realized by controlling the cycle times of chemical bath deposition.The efficiency of solar cell device under solar simulator?AM1.5?based on Fe₂O₃/BiOI photoanode was up to 0.55%,which the highest open circuit voltage and short circuit current of the solar cell could reach0.41 V and 4.89 mA·cm^-2,respectively.The fill factor?%?was 33.4.This study opens an available field to develop low-cost and environmentally friendly photoelectric materials for solar cells.2.A kind of Bi-doped Fe₂O₃ thin film electrode was synthesized by hydrothermal method which was grown on the FTO conductive glass substrate.By controlling the amount of Bi?NO₃?₃·5H₂O,the Bi-doped Fe₂O₃ electrodes with different molar ratio of Fe and Bi can be obtained.The Bi-doped Fe₂O₃ electrodes'nanostructure remained the original state,while the photoelectric performance such as the light current,optical voltage all had significant improvements when comparing with pure Fe₂O₃ electrode.The solar cell based on this Bi-doped Fe₂O₃ electrode showed excellent photoelectric properties,the photoelectric conversion efficiency was up to 0.200%,which the fill factor?%?was 25.0,the highest open circuit voltage and short circuit current of the solar cell could reach 0.30 V and 2.67 mA·cm^-2,respectively.