Through precursor, subsequent calcination and ammoniation, gallium nitride nanofibers (GaN-NFs) and gallium nitride nanoparticles (GaN-NPs) were synthesized by electrospinning and sol-gel method, respectively. The structure and morphology characteristics of the products were investigated by X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), energy dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM) and Brunauer-Emmett-Teller (BET) nitrogen adsorption-desorption measurements. Gas sensors were fabricated as side-heated structure. The ethanol sensing properties of the GaN-NFs and GaN-NPs were compared at operating temperatures from 280 to 360 degrees C and ethanol concentrations ranging from 50 to 1000 ppm. The results indicate that the porous GaN-NFs show improved response to ethanol with good selectivity, which is attributed to the 1D porous nanostructure. The ethanol sensing mechanism of the porous GaN-NFs was also discussed. (C) 2014 Elsevier B.V. All rights reserved.