Spectroscopic and photoluminescence properties of praseodymium doped potassium aluminum phosphate (P2O5-K2O-Al2O3) glasses for optoelectronics applications.

Praseodymium doped potassium aluminum phosphate (P ₂O ₅-K ₂O-Al ₂O ₃) glasses with various proportions of the Pr ³⁺ ions were synthesized using a facile melt-quenching method. The prepared modified (P ₂O ₅-K ₂O ₃-Al ₂O ₃ ) glasses were characterized using techniques such as X-ray diffraction (XRD), Fourier transforms infrared spectroscopy (FTIR), absorption spectra, and photoluminescence (PL). The XRD results confirmed the amorphous nature of all the prepared (PKAP) glass samples. The presence of various bending and stretching vibrations of the PKAP glass network was identified from the FTIR analysis. The band structure and energy gap of PKAP glass materials have been found from absorption spectra. A total of eight absorption peaks were observed, three absorption peaks are in the violet region of the spectrum, while an isolated absorption band is in the visible region, and the remaining five intense bands are in the near infrared region. The transition ³H ₄→ ³P ₂ (446 nm) is a hypersensitive transition. The decrease in energy band gap ( E g opt ) confirms the disorderness in the PKAP glass structure. The PL results indicated five broadband emissions, whereas an intense transition of ¹D ₂→ ³H ₄ at wavelength 604 nm corresponding to the reddish-orange region was observed. The present study elaborates that the emission quenching for all the observed bands occurs at a molar proportion of 1.0 mol%. The x, y coordinates of the as prepared glass samples passes through the reddish orange regions of the spectrum in comparison to the CIE 1931 diagram. This study demonstrates the suitability of these P ₂O ₅-K ₂O-Al ₂O ₃ glasses for orange LED and their probable applications in the optoelectronics field.