All biogenic phosphors: Albumen, chlorophylls, silk fibroin toward biohybrid white light-emitting diodes

Abstract

White light-emitting diodes (WLEDs) integrating natural luminophores into hybrid architectures provide promising strategies for sustainable and stable lighting solutions. However, their fundamental emission mechanisms remain insufficiently explored. In this work, we successfully fabricated biohybrid WLEDs (BioHWLEDs) via layer-by-layer (LbL) assembly of biophosphor heterostructures composed of chlorophyll, albumen, and silk fibroin. Steady-state photoluminescence (PL) profile revealed enhanced and broadened chlorophyll emission with albumen incorporation. The albumen-chlorophyll LbL (Alb/Chl LbL) films exhibited strong PL-absorption spectral overlap indicative of the Forster-type resonant energy transfer (FRET). This mechanism was corroborated by time-resolved PL studies, obtaining an improved and quantified FRET efficiency of 52.96%. The resulting BioHWLEDs demonstrated an electrically tunable color output and further achieved near-pure white chromaticity coordinates (0.33, 0.30) after silk fibroin addition, alongside excellent operational stability. This study highlights the potential of structured biomaterials as eco-friendly phosphors for advancing tunable and solid-state lighting technologies.