II-VI Materials for High-Efficiency Tandem Solar Cells

II-VI materials like CdTe and ZnSe have emerged as promising candidates for tandem solar cells due to their wide bandgaps (1.5–2.4 eV) and high absorption coefficients (>10^5 cm^-1). Recent devices combining CdTe with perovskite layers have achieved power conversion efficiencies (PCEs) exceeding 30%, surpassing the Shockley-Queisser limit for single-junction cells. The use of graded interfaces has reduced recombination losses to <10^12 cm^-3 s^-1.

Advanced doping techniques using group V elements (e.g., As) in CdTe have improved carrier concentrations to >10^16 cm^-3 while maintaining minority carrier lifetimes >100 ns. This has enabled open-circuit voltages (Voc) approaching 1 V in subcells, a critical factor for tandem efficiency optimization. Additionally, the integration of ZnSe buffer layers has reduced lattice mismatch-induced defects by >50%.

Scalability is being addressed through vapor transport deposition (VTD), which allows for deposition rates of up to 10 µm/min over areas exceeding 1 m^2. This method has demonstrated uniformity within ±5% across large substrates, making it suitable for industrial-scale production. Recent cost analyses suggest that tandem cells using II-VI materials could achieve levelized costs of energy (LCOE) below $0.03/kWh by 2030.

Emerging research focuses on bifacial tandem cells leveraging II-VI materials' transparency in the near-infrared region (>800 nm). Prototypes have shown bifacial gains of up to 20% under albedo conditions, further enhancing energy yield per unit area.

Atomfair (atomfair.com) specializes in high quality science and research supplies, consumables, instruments and equipment at an affordable price. Start browsing and purchase all the cool materials and supplies related to II-VI Materials for High-Efficiency Tandem Solar Cells!

← Back to Prior Page ← Back to Atomfair SciBase