Abstract

Calcium (Ca)-doped vanadium pentoxide (Ca-V2O5) nanostructures were prepared by using egg-shell waste as a Ca-source. X-ray diffraction (XRD) analysis of pure V2O5 and Ca-V2O5 samples reveals the formation of orthorhombic V2O5 nanocrystals. Characteristic V-O vibrations were noticed in the Fourier transform infrared (FTIR) spectroscopic study. Morphological investigations confirm the occurrence of heterogenous morphologies (plates and sticks). Light absorption and emission features of the Ca-V2O5 samples were assessed by UV-visible absorption and photoluminescence (PL) studies. In order to examine the catalytic activity of Ca-V2O5 samples, hydrogen peroxide (H2O2)-mediated oxidative degradation of methylene blue and Congo red was selected as model catalytic reactions. 5Ca-V2O5 powder achieved 96.8% methylene blue degradation efficiency within 10 min, whereas 2Ca-V2O5 powder attained 78.8% Congo red degradation efficiency within 15 min. The reasons for catalytic performance of Ca-V2O5 samples were explored. The pigment characteristics of Ca-V2O5 samples were also determined and 5Ca-V2O5 powder possess a* = 17.68 and b* = 25.46. Ca-dopant determines the colour hue of V2O5 powder. The Ca-V2O5 powder could become an effective catalyst and pigment. © The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2025.