Indium-antimony-halide single crystals for high-efficiency white-light emission and anti-counterfeiting

Although single-source white emissive perovskite has emerged as a class of encouraging light-emitting material, the synthesis of lead-free halide perovskite materials with high luminous efficiency is still challenging. Here, we report a series of zero-dimensional indium-antimony (In/Sb) alloyed halide single crystals, BAPPIn 2–2 x Sb 2 x Cl 10 (BAPP = C 10 H 28 N 4 , x = 0 to 1), with tunable emission. In BAPPIn 1.996 Sb 0.004 Cl 10 , bright yellow emission with near 100% photoluminescence quantum yield (PLQY) is yielded when it was excited at 320 nm, which turns into bright white-light emission with a PLQY of 44.0% when excited at 365 nm. Combined spectroscopy and theoretical studies reveal that the BAPP 4+ -associated blue emission and inorganic polyhedron–afforded orange emission function as a perfect pair of complementary colors affording white light in BAPPIn 1.996 Sb 0.004 Cl 10 . Moreover, the interesting afterglow behavior, together with excitation-dependent emission property, makes BAPPIn 2–2 x Sb 2 x Cl 10 as high-performance anti-counterfeiting/information storage materials.