In-situ packaging ultra-uniform 3D hematite nanotubes by polyaniline and their improved gas sensing properties

Abstract

This paper reports the PANI (polyaniline)-packaged three-dimensional (3D) α-Fe2O3 nanotubes P/N heterojunction, which was constructed successfully though a facile hydrothermal reaction without adding any surfactant followed by in-situ chemical polymerization in the liquid phase. The structure and morphology of the products were characterized by means of FESEM, XRD, TEM & HRTEM, TGA and FT-IR. Gas sensing test results found that, the PANI/α-Fe2O3 nanocomposite sensor exhibited obviously higher response, lower working temperature (180 °C), fast response and recovery speeds, good selectivity and excellent stability to acetone gas, indicating its promising application for high-performance acetone sensors. The enhanced gas sensing performances can be attributed to the factors like ultra-uniform 3D nanotube-like structure for α-Fe2O3, the noticeable advantages of PANI, as well as the construction of heterojunction barrier at their interface. The as-prepared PANI/α-Fe2O3 nanocomposite may be also applied in other areas like photocatalysis, water purification, ion batteries, optical devices, and so on.