Synthesis and luminescent performances of Ca2AlNbO6:Cr3+ perovskite phosphor

•New near-infrared-emitting Ca2AlNbO6:Cr3+ are successfully synthesized in air.•PLE spectrum derives from the transitions 4A2 → 4T1(4P), 4T1(4F), and 4T2(4F) of the Cr3+ ions.•Ca2AlNbO6:Cr3+ emits near-infrared light owing to the 2E → 4A2 and 4T2(4F) → 4A2 transitions.•Luminous center (Cr3+) is confirmed by time-resolved spectra and PL spectra under different excitation wavelength. Due to their applications in lighting, imaging, security, night vision, optoelectronics and other fields, far-red to near-infrared luminescence materials have attracted significant interest. Efficient pure phase Ca2AlNbO6:Cr3+ phosphor is synthesized in air. The excitation spectrum of Ca2AlNbO6:Cr3+ can be observed in the range of 260–700 nm because of the transitions 4A2 → 4T1(4P), 4T1(4F), and 4T2(4F) of the Cr3+ ions. Ca2AlNbO6:Cr3+ emits far-red to near-infrared light with peaks at 745 and 755 nm in the range of 650–880 nm due to the transitions 2E → 4A2 and 4T2(4F) → 4A2 of the Cr3+ ion. The concentration dependent spectra of Ca2AlNbO6:Cr3+ confirm that 0.4 mol% is the optimal concentration of Cr3+ ions in Ca2AlNbO6:Cr3+. The emission spectra under different excitation wavelength and time-resolved emission spectra indicate that Cr3+ is the only luminous center in Ca2AlNbO6:Cr3+. As Cr3+ is added from 0.2 mol% to 1.0 mol%, the lifetime of Ca2AlNbO6:Cr3+ decreases in turn from 3.25 ms to 2.82 ms. The temperature dependent spectra prove a good thermal stability of Ca2AlNbO6:Cr3+. The paper content can be applied to develop new Cr3+-doped luminescence materials in the future.