All Bio-Phosphors for Highly Performing Low-Energy Biohybrid Light Emitting Diodes

Bio-phosphors have emerged as an alternative to rare-earth color down-converting filters in light-emitting diodes (LEDs). They are mainly produced with biogenic emitters, like Fluorescent Proteins (FPs), embedded in polymer matrices.^1–3 The first biohybrid LED (Bio-HLED) with FP-phosphors featured a loss &lt;10% of the emission intensity after 100 h.¹ This performance was recently enhanced using zero-thermal quenching PMMA-FP phosphors, reaching &gt;150 days and 5 min of stability at low and high powers.⁴ However, the ideal combination of highly efficient and stable fully biogenic phosphors is still in its infancy.⁵ Here, we disclose the optimization of a bio-derived biodegradable polymer hosting and stabilizing a natural red FP – <i>mCherry,</i> as red-emitting phosphor in Bio-HLEDs. The photoluminescent properties of the bio-phosphors - PLQY&gt; 20% with λ_em = 630 nm - led to Bio-HLEDs with excellent photostabilities &gt; 2000 h operating, representing 2 orders of magnitude enhancement. We are strongly convinced that our work represents a crucial breakthrough in the development of red emitting bio-phosphors and in the stabilization of further natural FPs.<br/>1. Weber, M. D. <i>et al.</i> Bioinspired Hybrid White Light-Emitting Diodes. <i>Adv. Mater.</i> <b>27</b>, 5493–5498 (2015).<br/>2. Fernández Luna, V. <i>et al.</i> Deciphering Limitations to Meet Highly Stable Biohybrid Light Emitting Diodes. <i>Adv. Funct. Mater.</i> <b>29</b>, 1904356 (2019).<br/>3. Aguino, C. F. <i>et al.</i> Single-Component Biohybrid Light-Emitting Diodes Using a White-Emitting Fused Protein. <i>ACS Omega</i> <b>3</b>, 15829–15836 (2018).<br/>4. Espasa, A. <i>et al.</i> Long-living and Highly Efficient Biohybrid Light Emitting Diodes with Zero-thermal-Quenching Biophosphors. <i>Nat. Commun.</i> <b>11</b>, 1–10 (2020).<br/>5. Fernández-Luna, V. <i>et al.</i> Biogenic Fluorescent Protein-silk Fibroin Phosphors for High Performing Light Emitting Diodes. <i>Mater. Horizons</i> <b>7</b>, 1790–1800 (2020).