Novel CuIn_1-xGa_xTe₂ Structures for High Efficiency Photo- electrochemical Solar Cells

摘要

Novel CuIn1-xGaxTe2 (CIGT; x =0, 0.3, 0.5 and 0.7) chalcopyrite structures for photo-electrochemicalsolar cells have been successfully synthesized via a facile co-precipitation method. Briefly, tetragonalchalcopyrite structure was perceived with as-synthesized CIT sample whereas chalcopyrite phase wasaccompanied with minor impurity phases of cubic In2O3 and hexagonal Te metal with increasing the3+ Ga ion ratio. Meanwhile, a slight increase in the unit cell volume of chalcopyrite crystals was3+ 3+ observed with the substitution In ions with different ratios of Ga ions. Moreover, the microstructurecharacteristics of the as-prepared chalcopyrite samples were exhibited different morphologies with3+ different Ga ion concentrations. Furthermore, the band gap energy and calculated refractive index3+ were leaned on the Ga ion content. Generally, the J-V characteristic measurements were coherentlyperformed for the corresponding photo-electrochemical solar cells using the as-prepared photo- electrode materials. Accordingly, CuIn0.3Ga0.7Te2 sample was displayed the highest photovoltaicperformance with conversion efficiency ( ) ~ 6.19 % and fill factor (FF) ~ 24.98 %, respectively. Thesuperior power conversion performance was discussed based on the electrochemical impedance spectra(EIS) results which confirmed the enhanced electronic conductivities of the as-preparedphotoelectrodes and exhibited well agreement with the obtained optical properties as well as J-Vmeasurements.