Cr- and Sb-containing TiO 2 inorganic orange nano-pigments prepared by a relative long hydrocarbon chain polyol

Abstract We report the preparation of a series of orange Cr- and Sb-containing TiO 2 nano-pigments by the polyol via using triethylenglycol (TEG). Poorly crystallized anatase nanopowders with nominal stoichiometric compositions Cr x Sb x Ti 1−2x O 2 , with 0 ≤ x ≤ 0.2, were obtained by heating at 180 °C a solution of antimony acetate, chromium acetylacetone and titanium butoxide in TEG. The transition temperature of the chromium- and antimonium-containing anatase nanoparticles into the rutile crystalline form occurred over the range of temperature between 500 and 650 °C, depending on the dopant amount. After annealing at 800 °C for short time the series of samples displaying the rutile structure were analysed by different techniques. Results from energy dispersive X-ray (EDX) analysis and lattice volume of the rutile nanoparticles indicated that the content of dopants increased over the whole range of studied compositions. Field emission scanning electron microscopy (FESEM) images proved the formation of discrete, non-aggregated Cr- and Sb-codoped rutile nano-pigments with sizes below 100 nm after annealing precursors at 800 °C. Zeta (ζ) potential of aqueous dispersions of nano-pigments confirmed the feasibility to be used in the ink-jet printing decoration process. The chromatic coordinates of the series of prepared orange nano-pigments were similar to both the micrometric prepared by conventional techniques and the nanometric synthesized by the so-called CERCOL method. Also the b* chromatic coordinate values after glazing nano-pigments annealed at different temperatures up to 800 °C were comparable to the ones reported in the literature.