Effective red emission of Sb3+ sensitized Ho3+ doped Cs2NaGdCl6 perovskite under blue excitation

Red LEDs excited by blue light have a wide range of applications in plant growth due to their simple structure. The preparation of efficient red phosphors has attracted much attention from researchers. In this paper, Cs2NaGdCl6:Ho3+ Sb3+ phosphors were synthesized by the solvothermal method, which produced the characteristic emission of Ho3+5F5→5I8 at 655 nm under 460 nm excitation. The red light at 655 nm is further enhanced after the introduction of Sb3+, and the quantum efficiency can reach 39.85 %. The luminescence mechanism and energy transfer of Sb3+ and Ho3+ were further investigated. The produced phosphor was encapsulated with a 460 nm blue chip into an LED to realize red and blue dual emission, which meets the demand for blue and red light for plant growth. •A double perovskites phosphor Cs2NaGdCl6:Ho3+ Sb3+ was synthesized.•The emission spectrum excited by the blue light chip matches well with the plant absorption spectrum.•Synthesis of a halide double perovskites with good thermal stability.•The materials show promising application in the field of plant cultivation.