Silica-Coated Mn-Doped CsPb(Cl/Br) Inorganic Perovskite Quantum Dots: Exciton-to-Mn Energy Transfer and Blue-Excitable Solid-State Lighting.

Tunability of emitting colors of perovskite quantum dots (PQDs) was generally realized via composition/size modulation. Due to their bandgap absorption and ionic crystal features, the mixing of multiple PQDs inevitably suffers from reabsorption and anion-exchange effects. Herein, we address these issues with high-content Mn-doped CsPbCl PQDs that can yield blue-excitable orange Mn emission benefited from exciton-to-Mn energy transfer and Cl-to-Br anion exchange. Silica-coating was applied to improve air stability of PQDs, suppress the loss of Mn, and avoid anion-exchange between different PQDs. As a direct benefit of intense multicolor emissions from Mn-doped PQD@SiO solid phosphors, a prototype white light-emitting diode with excellent optical performance and superior light stability was constructed using green CsPbBr@SiO and orange Mn: CsPb(Cl/Br)@SiO composites as color converters, verifying their potential applications in the field of optoelectronics.