Unveiling the Influence of the Spectral Irradiance of Indoor Light-Emitting Diodes on the Photovoltaics of a Methylammonium Lead Iodide-Based Device

An understanding of the spectrum–property relationship of perovskite solar cells when illuminated by light-emitting diodes that are used for indoor applications is necessary. Herein, it is aimed to explore the influences of correlated-color temperatures on a MAPbI₃-based device under low-light conditions. Given an irradiance of approximately 3 W m⁻² (or ≈1000 lx), a maximum free carrier generation rate of 1.0 × 10²¹ m⁻³ s⁻¹ was found. Additionally, power conversion efficiencies (PCEs) up to 31.97%, 30.36%, and 28.98% with maximum power outputs of 13.66, 13.02, and 16.09 μW could be reached at 3000, 4000, and 6500 K, respectively. Additional increases in the PCEs were observed when high-energy blue light (in a range of 400–550 nm) was excluded during the current–voltage sweeps. In combination with the surface photovoltage measurements, intense blue light (under 6500 K) had a minimal influence on the photoinduced charge separation signals when compared to those caused by 3000 and 4000 K light. As a solar cell, the PCE reached as high as 34.52%, which corresponded to 73.08% of the thermodynamic limit of its bandgap at 3000 K.