Electron structure and photocatalytic properties of (Na/K)VMoO6 nanosuspensions

Electron structure features of nanopowders with composition of (Na/K)VMoO6 have been investigated both experimentally and theoretically. The dispositions of valence edge and conduction band were determined experimentally for vacuum condition by X-ray photoelectron spectroscopy, UV–visible and impedance spectroscopy and evaluated theoretically for water solutions. The additional absorbance band in the band gap has been found for both compounds, which leads to electron conductivity at low-temperature range (250–350 °C). Nanopowders have been prepared by sol-gel method with further ground in the planetary mill. Prepared powders in water solution have formed nanosuspension with size's particle up to 100 nm for NaVMoO6 and 400 nm for KVMoO6, which is hardly sedimentated. The highly effective photocatalytic ability under visible light irradiation of the prepared compounds was observed using methylene blue decomposition process. The almost full methylene blue (20 mg/L) degradation is observed during 30 min for 10 mg of the photocatalysts. The investigation of possible dye degradation pathway has showed the high depth of decomposition. [Display omitted] •The (Na/K)VMoO6 water nano suspensions have been prepared.•The electron structure of the compounds has been determined experimentally.•The high phototcatalytic activity of (Na/K)VMoO6 under visible light has been found.•The active radical species generated by (Na/K)VMoO6 has been investigated.•The MB decomposition products have been defined.