Alkali Dispersion in (Ag,Cu)(In,Ga)Se₂ Thin Film Solar Cells-Insight from Theory and Experiment.

ABSTRACT: Silver alloying of Cu(In,Ga)Se₂ absorbers for thin film photovoltaics offers improvements in open-circuit voltage, especially when combined with optimal alkali-treatments and certain Ga concentrations. The relationship between alkali distribution in the absorber and Ag alloying is investigated here, combining experimental and theoretical studies. Atom probe tomography analysis is implemented to quantify the local composition in grain interiors and at grain boundaries. The Na concentration in the bulk increases up to ∼60 ppm for [Ag]/([Ag] + [Cu]) = 0.2 compared to ∼20 ppm for films without Ag and up to ∼200 ppm for [Ag]/([Ag] + [Cu]) = 1.0. First-principles calculations were employed to evaluate the formation energies of alkali-on-group-I defects (where group-I refers to Ag and

SUBMITTER: Aboulfadl H 

PROVIDER: S-EPMC7898268 | biostudies-literature | 2021 Feb

REPOSITORIES: biostudies-literature