Photoluminescence studies of green emitting BaB₈O₁₃: Bi³⁺ phosphors prepared by solution combustion method

Undoped and bismuth (Bi³⁺)-doped barium octaborate (BaB₈O₁₃) powder phosphors were synthesized by solution combustion method. X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, UV–visible and photoluminescence spectroscopy were used to characterize the phosphors. X-ray diffraction patterns confirmed the formation of orthorhombic phase of BaB₈O₁₃. Scanning electron microscopy images showed agglomeration of particles with irregular shapes. The infrared stretching frequencies detected in the spectral wavelength range of 650–1600 cm⁻¹ also confirmed the formation of the BaB₈O₁₃ host while the photoluminescence and the energy dispersive X-ray spectroscopy data confirmed the incorporation of Bi³⁺ ions in the BaB₈O₁₃ host lattice. The broad photoluminescence emission due to ¹S₀–³P₁ transitions of Bi³⁺ ions was observed at 548 nm in the green region of the visible spectrum after exciting the powder phosphors at a wavelength of 271 nm using a monochromatized xenon lamp. The highest photoluminescence intensity was observed from BaB₈O₁₃: 0.11Bi³⁺ with the CIE coordinates of x = 0.3267 and y = 0.6004, suggesting that this phosphor can be used as a source of green light in light emitting devices of different types.