Investigation on photoluminescence and photocatalytic behavior of BiPO₄:Pr

The hydrothermal method was used to synthesize BiPO₄ and BiPO₄ with varying concentrations of praseodymium. X-ray diffraction confirmed the crystal structure of the samples as low-temperature monoclinic, and substituting the Pr³⁺ ion in the Bi³⁺ site did not affect the crystal structure. Functional group analyses showed vibrational modes corresponding to Bi[sbnd]O and PO₄ bonds. UV–vis DRS spectra indicated the presence of bands corresponding to Bi[sbnd]O transition, and a minor reduction in band gap was seen with the substitution of Pr. The excitation and emission spectra of BiPO₄:Pr³⁺ were recorded to study the luminescene behavior of Pr ion in BiPO₄. Emission intensity quenching occurred at Pr concentrations greater than 1.5 %. The samples' photocatalytic performance was examined by degrading the organic dye rhodamine B under a UV light source. Pr concentration of 1.5 % sample exhibited a better degradation rate when compared to BiPO₄ and other Pr-doped BiPO₄ samples. The stability of the photocatalyst was confirmed using the XRD pattern.