High-performance room temperature NH3 sensor based on zigzag morphology TiO2 nanorods

Abstract

Nanostructured materials present another alternative solution to improving the performance of gas sensors, which depends largely on their morphology. In this paper, the effects of different TiO2 nanostructures on the gas sensing properties of NH3 are explored through both experimentation and molecular dyanamics (MD) simulation. During the experiment, TiO2 nanofilms, upright nanorods and zigzag nanorods are produced by means of glancing angle deposition (GLAD), while the nanostructures are characterized by scanning electron microscopy and X-ray powder diffraction. The test on concentration gradient, repeatability, and selectivity of NH3 is conducted at room temperature. It is demonstrated that the nanostructures with distinct morphologies vary in gas sensing properties for NH3. Notably, the 1 fold zigzag nanostructure outperforms other structures in NH3 response. During the simulation process, the performance of various structures in adsorbing gas molecules is simulated through molecular dynamics to verify the relevant experimental results. Both experimental and simulation results show that 1 fold zigzag nanostructures are promising in terms of NH3 sensing.