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Creators/Authors contains: "Yan, Yanfa"

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  1. Free, publicly-accessible full text available August 16, 2024
  2. Free, publicly-accessible full text available June 1, 2024
  3. Free, publicly-accessible full text available May 1, 2024
  4. A phosphorus-containing Lewis-base molecule passivates and bridges perovskite grain boundaries and interfaces. 
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  5. Abstract

    Bandgap gradient is a proven approach for improving the open-circuit voltages (VOCs) in Cu(In,Ga)Se2and Cu(Zn,Sn)Se2thin-film solar cells, but has not been realized in Cd(Se,Te) thin-film solar cells, a leading thin-film solar cell technology in the photovoltaic market. Here, we demonstrate the realization of a bandgap gradient in Cd(Se,Te) thin-film solar cells by introducing a Cd(O,S,Se,Te) region with the same crystal structure of the absorber near the front junction. The formation of such a region is enabled by incorporating oxygenated CdS and CdSe layers. We show that the introduction of the bandgap gradient reduces the hole density in the front junction region and introduces a small spike in the band alignment between this and the absorber regions, effectively suppressing the nonradiative recombination therein and leading to improved VOCs in Cd(Se,Te) solar cells using commercial SnO2buffers. A champion device achieves an efficiency of 20.03% with a VOCof 0.863‚ÄČV.

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  6. null (Ed.)