Nanoscale heterophase regulation enables sunlight-like full-spectrum white electroluminescence.

Traditional white light-emitting diodes operate by exciting phosphors using blue light-emitting diodes, leading to the absence of specific colour bands compared with the visible light region of the sunlight spectrum (400-780 nm), and excess blue light increases the risk of harmful effects on ecosystems and organisms. Here, we precisely design and regulate heterophase γ/δ-CsPb(I/Cl)(3) at the nanoscale for uniform heterophase distribution, balanced flow of charges and tunable spectrum. Then, γ/δ-CsPb(I/Cl)(3) directly excited by electricity shows full-spectrum white electroluminescence covering 400-780 nm with standard Commission Internationale de l'Eclairage coordinates of (0.33, 0.33), a Colour Rendering Index of 95, a Correlated Colour Temperature of 5829 K and a Delta u,v of -3 × 10(-4), accompanied with balanced white light composition (Melanopic ratio = 1.004). The match indices of such five core indicators to standard sunlight reach 100%, 95% (97% for R(9)), 99.5%, 99.97% and 99.6%, respectively, far ahead of as-fabricated commercial white light-emitting diodes.