Investigation on lead-free Mn-doped Cs2NaInCl6 double perovskite phosphors and their optical properties

Doping with transition metal ions in lead-free double perovskite material of Cs2NaInCl6 has been highly spotlighted for tailoring optical properties and advancing light-emitting applications. Herein, solvothermal method is employed to synthesizing Mn-doped Cs2NaInCl6 phosphors with a purpose of imparting new optical properties in the visible light region. X-ray diffraction, scanning electron microscope, X-ray photoelectron spectroscopy, thermogravimetric analysis, electron paramagnetic resonance and photoluminescence (PL) techniques confirm that Mn-doped Cs2NaInCl6 exhibits stable double perovskite crystal structure, good stability, and exceptional electronic properties. Mn-doped Cs2NaInCl6 also shows observable red fluorescence peaking at 610 nm with PL decay lifetime of about 0.21 ms and PL quantum yield of about 5%, owing to the 4T1→6A1 transition of the Mn d electron.