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Close-Space Sublimation-Deposited Ultra-Thin CdSeTe/CdTe Solar Cells for Enhanced Short-Circuit Current Density and Photoluminescence
Published on: March 6, 2020
Ultrafast charge carrier relaxation and charge transfer processes in CdS/CdTe thin films
Bill Pandit1, Ruvini Dharmadasa, I M Dharmadasa
1Department of Chemistry, University of Louisville, Louisville, Kentucky 40292, USA. j.liu@louisville.edu.
Abstract:
Ultrafast transient absorption pump-probe spectroscopy (TAPPS) has been employed to investigate charge carrier relaxation in cadmium sulfide/cadmium telluride (CdS/CdTe) nanoparticle (NP)-based thin films and electron transfer (ET) processes between CdTe and CdS. Effects of post-growth annealing treatments to ET processes have been investigated by carrying out TAPPS experiments on three CdS/CdTe samples: as deposited, heat treated, and CdCl2 treated. Clear evidence of ET process in the treated thin films has been observed by comparing transient absorption (TA) spectra of CdS/CdTe thin films to those of CdS and CdTe. Quantitative comparison between ultrafast kinetics at different probe wavelengths unravels the ET processes and enables determination of its rate constants. Implication of the photoinduced dynamics to photovoltaic devices is discussed.
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