Nd3+ doped BaAl2O4 for enhanced photocatalytic degradation of methylene blue

•Slight Nd3+ doping concentration in BaAl2O4 renders best photocatalytic efficiency.•BaAl2O4:Nd (0.1%) degrades MB three times faster than undoped BaAl2O4.•Slight Nd3+ concentrations around 0.1 mol% promote increased charge carriers.•Nd3+ concentrations around 1.0 mol% promote a higher recombination PL.•Nd3+ concentrations higher than 1 mol% lead to increased traps and low PL. Neodymium doped barium aluminates of hexagonal phase were prepared by combustion synthesis. The photocatalysts were characterized by X-ray diffraction, UV–Vis spectroscopy and photoluminescence spectroscopy. The photocatalytic performance of BaAl2O4:Nd3+ was evaluated through their role in the degradation of 15 ppm of methylene blue (MB) dye under solar radiation. Superior photocatalytic degradation of MB was achieved with only a 0.1 mol% Nd3+ doping percentage. The lightly Nd3+ doped photocatalyst rendered a degradation percentage rate that was three times faster than that of the undoped photocatalyst. The results suggest a nonlinear dependence of photoluminescence and photocatalytic activity on Nd3+ concentration.