Abstract
We inserted Cu(In,Ga)3Se5 into the CdS/Cu(In,Ga)Se2 interface of Cu(In,Ga)Se2 solar cells with a flat band profile and energy bandgaps (Eg) of 1.2 and 1.4 eV in order to investigate the repelling of holes by the effect of valence band offset (ΔEv). We found that open circuit voltage (VOC) was clearly improved from 0.66 to 0.75 V with Eg of 1.4 eV, although VOC was only increased from 0.63 to 0.64 V with Eg of 1.2 eV. For high efficiency, we fabricated Cu(In,Ga)Se2 solar cells with a single-graded band profile and an average Eg of 1.4 eV. Eventually, a conversion efficiency of 14.4% was obtained when Cu(In,Ga)3Se5 with a thickness of 30 nm was inserted, although the conversion efficiency was 10.5% without Cu(In,Ga)3Se5. These results suggest the importance of ΔEv in the suppression of interfacial recombination by repelling holes and possibility that the highest efficiency of Cu(In,Ga)Se2 solar cells with an average Eg of 1.4 eV could be achieved.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.