Two different routes to obtain SnO 2 nanoparticles, undoped and doped with rare earth metals (Eu or Pr), are described herein. The first route was based on the polymeric precursor method that led to the obtainment of SnO 2 nanoparticles dispersed in amorphous silica. The second route was simply the impregnation with SnCl 4 aqueous solution of SiO 2 –CaO glass microparticles functionalized with hydroxyl ( − OH) groups. The materials were characterized by N 2 physisorption, XRD, EDS and TEM analyses. We also present the results of catalytic experiments involving the nanocrystalline composites in ethanol steam reforming. The catalytic properties of the undoped composites with SnO 2 supported on SiO 2 –CaO glass differ from their doped analogues, however, they were both selective towards ethylene formation, in contrast to the doped composite obtained by the polymeric precursor method.