ACS Applied Materials & Interfaces · 2021 · 74 citations · 64 references
EngineeringMaterials EngineeringMaterials ScienceElectronic MaterialsSemiconductor DevicesSemiconductor MaterialsDopingMetalsPhotovoltaic MaterialsSemiconductor Device MaterialsSolar Cell MaterialsSolar CellsAntisite DefectsBand Tail StatesDefect ClustersDevice EfficiencyEfficiencyExternal Quantum EfficiencyOpen-circuit VoltageQuantum Efficiency
Cation substitution in Cu₂ZnSn(S,Se)₄ can reduce the open‑circuit voltage deficit by modifying band‑tail states, antisite defects, and related defect clusters. The authors introduce a simple single‑step process that deposits a thin Ag layer on a metallic precursor to enhance the performance of (Agₓ,Cu₁₋ₓ)₂ZnSn(Sᵧ,Se₁₋ᵧ)₄ kesterite solar cells. This approach improves band‑tailing, extends minority carrier lifetime, improves diode factors, and reduces antisite defects and defect clusters compared to the parent CZTSSe material. The resulting ACZTSSe device achieved a 12.07 % efficiency with a record 561 mV Voc‑deficit, demonstrating that the thin Ag layer effectively suppresses defects and band‑tailing to lower the Voc‑deficit.
A cation substitution in Cu2ZnSn(S,Se)4 (CZTSSe) offers a viable strategy to reduce the open-circuit voltage (Voc)-deficit by altering the characteristics of band-tail states, antisite defects, and related defect clusters. Herein, we report a facile single process, i.e., simply introducing a thin Ag layer on a metallic precursor, to effectively improve the device characteristics and performances in kesterite (Agx,Cu1–x)2ZnSn(Sy,Se1–y)4 (ACZTSSe) solar cells. Probing into the relationship between the external quantum efficiency derivative (dEQE/dλ) and device performances revealed the Voc-deficit characteristics in the ACZTSSe solar cells as a function of Cu and Ag contents. The fabricated champion ACZTSSe solar cell device showed an efficiency of 12.07% and a record low Voc-deficit of 561 mV. Thorough investigations into the mechanism underpinning the improved performance in the ACZTSSe device further revealed the improved band-tailing characteristic, effective minority carrier lifetime, and diode factors as well as reduced antisite defects and related defect clusters as compared to the CZTSSe device. This study demonstrates the feasibility of effectively suppressing antisite defects, related defect clusters, and band-tailing characteristics by simply introducing a thin Ag layer on a metallic precursor in the kesterite solar cells, which in turn effectively reduces the Voc-deficit.
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Device Characteristics of CZTSSe Thin‐Film Solar Cells with 12.6% Efficiency
Wei Wang, Mark T. Winkler, Oki Gunawan et al. · Advanced Energy Materials · 2013 · 3.2K citations
Effects of heavy alkali elements in Cu(In,Ga)Se<sub>2</sub>solar cells with efficiencies up to 22.6%
Philip Jackson, Roland Wüerz, Dimitrios Hariskos et al. · physica status solidi (RRL) - Rapid Research Letters · 2016 · 1.5K citations · Full text
Natural Sciences, Materials Engineering, Materials Science +15