Physics / mechanism
Perovskite solar cells use ABX₃ crystal structures (typically methylammonium or formamidinium lead halide) as the absorber layer. Strong optical absorption (~10⁴–10⁵ cm⁻¹), long carrier diffusion lengths (>1 µm), and tunable bandgap (1.2–2.3 eV via halide substitution) make them compelling. Single-junction lab efficiency sits at ~26.1% (KAUST, 2024), approaching crystalline silicon’s ~29.4% theoretical limit. Tandem stacks—perovskite on silicon—have hit 33.9% (LONGi, 2024). Key failure modes: moisture/oxygen degradation, thermal instability above ~85°C, and lead toxicity. Lifetime under IEC 61215 conditions remains the commercial bottleneck.
Competitive landscape
Silicon PV is the incumbent at $0.20–0.25/W manufactured cost. CIGS and CdTe (First Solar) offer thin-film alternatives with better thermal stability but lower peak efficiency. III-V multijunctions (Spectrolab, SolAero) exceed 40% but at $50+/W—CPV niche only. Organic PV lags on efficiency (~19%). The real competitive axis is perovskite-silicon tandem vs. TOPCon/HJT silicon: same substrate, +5–8 pts efficiency, but perovskite adds deposition complexity and encapsulation cost.
Companies using
Connected ideas
Sources
Frontier (open questions)
- To be added.