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 MAPbI 3 ‐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 × 10 21 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.