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Open-Circuit Voltage Deficit in Cu2ZnSnS4 Solar Cells by Interface Band Gap Narrowing

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 نشر من قبل Ji-Sang Park
 تاريخ النشر 2018
  مجال البحث فيزياء
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There is evidence that interface recombination in Cu2ZnSnS4 solar cells contributes to the open-circuit voltage deficit. Our hybrid density functional theory calculations suggest that electron-hole recombination at the Cu2ZnSnS4/CdS interface is caused by a deeper conduction band that slows electron extraction. In contrast, the bandgap is not narrowed for the Cu2ZnSnSe4/CdS interface, consistent with a lower open-circuit voltage deficit.

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