Cs ₂ AgInCl ₆ :Cr ³⁺ ,Yb ³⁺ double perovskite single crystals was prepared by hydrothermal method, which shows NIR emission from 800 to 1400 nm with a peak at 1000 nm and a full-width at half maximum of 188 nm with a higher PLQY of ∼45% excited at 365 nm.