Rapid synthesis of hybrid methylammonium lead iodide perovskite quantum dots and rich MnI(2) substitution favouring Pb-free warm white LED applications

We present a facile room temperature synthesis of CH(3)NH(3)Pb(1−x)Mn(x)I(3) perovskite quantum dots (PQDs) substituting manganese (Mn(2+)) at the lead (Pb(2+)) sites to minimize environmental pollution and make it commercially feasible. By varying the concentration of Mn(2+) from 0 to 60%, the PQDs exhibit strong color tunability from red to orange color suggesting successful energy transfer due to Mn(2+) inclusion. We observed a high external photoluminescence quantum yield (PLQY) of 98% for unsubstituted CH(3)NH(3)PbI(3) and >50% for up to 15% Mn(2+) substituted PQDs. The average lifetime of PQDs was found to shorten with increasing Mn(2+) replacement. We demonstrate a white LED prototype by employing the CH(3)NH(3)Pb(1−x)Mn(x)I(3) PQDs with green QDs on a blue LED chip. The CRI and CCT value varying from 92 to 80 and 5100 K to 2900 K, respectively, indicate the usability of the Mn(2+) substituted PQDs as efficient warm white LEDs with a promising CRI and good stability.