Exploring the structural and optical properties of Eu3+, Sb3+ co-doping effect on Cs2NaInCl6 double perovskites for LEDs applications

In the present study Eu3+, Sb3+ co-doped Cs2NaInCl6 double perovskite has been synthesized by using the hot injected method. The crystal structure of the prepared samples has been investigated by XRD data with the help of Rietveld refinement analyzes. The obtained structural property result revealed that all the samples [Cs2NaInCl6, Sb3+ doped Cs2NaInCl6 and (Sb3+, Eu3+) co-doped Cs2NaInCl6] are crystallized in a cubic crystal structure with a space group Fm-3m (225). Further, the electronic properties have been performed by using UV absorbance spectroscopy. It shows that the electronic band gap of the Cs2NaInCl6 and Sb3+ doped compounds exhibits 4.8 eV and 3.9 eV respectively, which is good agreement with other results. The energy band gap value of Eu3+, Sb3+ co-doped Cs2NaInCl6 compounds exhibited similar to 4.0 eV, which is very close to Sb3+ doped Cs2NaInCl6 double perovskite. The Photoluminescence study revealed that Sb3+, Eu3+ co-doped Cs2NaInCl6 compounds exhibited dual emission from the self trapped excitation to Eu3+ ion. The blue emission (440 nm) is due to the transition of P-3(1) -> S-1(0) from Sb3+ ion and orange-red emissions (570-706 nm) are due to the transition of D-5(0) -> 7F1, D-5(0) -> F-7(2), D-5(0) -> F-7(3) and D-5(0) -> F-7(4) from Eu3+ ions. The dual emission behavior of the Sb3+, Eu3+ co-doped Cs2NaInCl6 double perovskites suitable for optoelectronic devices and light emitting diodes (LED's) applications.