  Metal halide perovskites (MHPs) based phosphor-converted light-emitting
diodes (pc-LEDs) are limited by the low MHP stability under storage/operation
conditions. A few works have recently stablished the in-situ synthesis of MHPs
into polymer matrices as an effective strategy to enhance MHPs stability with a
low-cost fabrication. However, this is limited within petrochemical-based
polymers. Herein, the first in-situ ambient preparation of highly luminescent
and stable MHPs-bio-polymer filters (MAPbBr3 nanocrystals as emitter and
poly(L-lactide acid) (PLLA) as matrix) with arbitrary areas (up to ca. 300 cm2)
is reported. The MAPbBr3-PLLA phosphors feature a narrow emission (25 nm) with
excellent photoluminescence quantum yields (more than 85%) and stabilities
under ambient storage, water, and thermal stress. This is corroborated in green
pc-LEDs featuring a low efficiency roll-off, excellent operational stability of
ca. 600 h, and high luminous efficiencies of 65 lm W-1 that stand out the prior
art (e.g., average lifetime of 200 h at 50 lm W-1). The filters are further
exploited to fabricate white-emitting pc-LEDs with efficiencies of ca. 73 lm
W-1 and x/y CIE color coordinates values of 0.33/0.32. Overall, this work
stablishes a straightforward (one-pot/in-situ) and low-cost preparation
(ambient/room temperature) of highly efficient and stable MHP-bio-polymer
phosphors for highly performing and more sustainable lighting devices.
