Nanostructured particles of Nd2NiO4+delta with controlled crystallinity, size and morphology have been prepared via ultrasonic spray pyrolysis. This is, to the best of our knowledge, the first time this technique has been used to synthesize this material which is of high interest for intermediate temperature solid oxide fuel cells (IT-SOFC). Spherical, submicron particles composed of nanosized crystallites of Nd2NiO4+delta are obtained at 1100 C for reaction times typically less than 10 s. Amorphous to highly crystalline powders are produced depending on the reaction temperature (700-1100 degrees C). The particle size can be adjusted in a broad range from 50 nm to 1 mu m by adjusting the initial precursor concentration and ultrasonic frequency while the powder morphology is controlled by the nature of the precursors and their concentration. (C) 2010 Elsevier B.V. All rights reserved.