The Polymer Society of Korea

정인아 (포항공과대학교)

조창순 (포항공과대학교)

Perovskite solar cells (PSCs) have rapidly advanced toward the detailed-balance limit, but reaching it ultimately requires near-perfect electroluminescence (EL). Despite ELQEs exceeding 8% in state-of-the-art devices, classical ray optics predicts an outcoupling ceiling of ~1/2n² (n ≈ 2.5). Here, we summarize our recent studies showing that photon recycling can overcome this constraint.

Owing to strong emission–absorption overlap, metal-halide perovskites exhibit pronounced photon recycling. In a highly radiative n–i–p PSC (26.0% efficiency), we measured an ELQE up to 19.7%, well beyond the classical limit. Optical modeling indicates a 32% increase in external radiation and an additional 1.2 mV photovoltage, highlighting the importance of optical design to maximize photon-recycling benefits.