InNhO(4) nanoparticles characterized by high crystallinity and particle sizes in the range of 10-30 nm (see TEM image) are synthesized by a soft-chemistry route involving the solvothermal reaction of indium acetylacetonate and niobium chloride in benzyl alcohol at 200 degrees C. The as-synthesized nanopowders offer a high photocatalytic activity under illumination with visible light.