Growth of Well Aligned Tin Oxide Nanotubes by a Sol-gel Method

Abstract

In previous works, the authors improved the characteristics of resistive gas sensors using SnO2 nanoparticles to build them. Upon the convenience to increase the surface dimension to enhance the gas absorption area, well aligned SnO2 nanotubes were prepared by sol-gel method within the pores of a polycarbonate template to increase the sensing surface. To optimize the nanotubes synthesis, some parameters affecting the nanotubes morphology were varied and the effects of the different parameters on morphology were compared: the pores size of template membrane, the calcination temperature and time, the precursor solution concentration and the solution aging temperature and time, finding the most convenient conditions to grow the nanotubes. Characterization of nanotubes was performed with XRD being found that the tetragonal rutile was the only crystalline phase exhibited by the polycrystalline nanotubes and their morphology was observed by FE-SEM, discussing the relation among the measured data and the varied parameters affecting the process.