Lanthanide orthovanadates, CeVO4, PrVO4, and NdVO4, of nanodimensions were synthesized under microwave exposure, and the photocatalytic activities of these compounds were investigated. These compounds exhibit a tetragonal zircon structure, crystallizing in the space group I41/amd with a = 7.3733(4) and c = 6.4909(4) Å with Z = 4. The crystal structure was analyzed by powder X-ray diffraction, and the band gap was analyzed by UV-visible spectroscopy. Particle sizes were in the range of 25-30 nm, as observed by transmission electron microscopy. While the energy dispersive X-ray analysis indicates the formation of LnVO4, thermal analysis of these solids shows stability of the phase up to 1000°C. The photocatalytic activity of all these orthovanadates has been investigated by degrading various dyes like methylene blue (MB), Orange G (OG), Rhodamine B (RB), Rhodamine Blue (RBL), and Remazol brilliant blue (RBBR) under UV irradiation. Further, these compounds were also used to degrade organic pollutants like phenol, 2,4-dinitrophenol and 2,4-dichlorophenol. The degradation rates of dyes and organics in presence of microwave-synthesized orthovanadates are higher compared to that observed with orthovanadates synthesized by the solid state technique. The microwave-synthesized orthovandates also show chloro-specificity, with the rate of degradation of 2,4-dichlorophenol significantly higher than that observed in presence of Degussa P-25 titania. © 2008 American Chemical Society.