The microwave assisted reaction between P25 titanium dioxide (TiO2) and phenylphosphonic acid (PPA) is explored thoroughly and the influence of the reaction conditions on the grafting mechanism and formed products is presented. While the surface grafting is observed at low temperatures and water free conditions, the formation of titaniumphosphonate is favored in water and high reaction temperatures. For the first time the correlation between the amorphous TiO2 phase and the formation of titani-umphenylphosphonate is reported. Materials are fully characterized by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), solid-state P-31 Nuclear Magnetic Resonance (P-31 NMR) spectroscopy, energy dispersive X-ray (EDX) spectroscopy and transmission electron microscopy (TEM). (C) 2016 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved.