Combination of PPy with three-dimensional rGO to construct bioinspired nanocomposite for NH3-sensing enhancement

Abstract

For general nanoparticle-like gas-sensing materials, high dispersion, low agglomeration, and high active surface available for gas adsorption are highly desirable for achieving high sensing performance. Inspired from the distribution structure of olfactory cells of mice, this work describes a macroporous nanocomposite of polypyrrole/three-dimensional reduced graphene oxide (PPy/3D-rGO) with biomimetic structure for highly sensitive application. The PPy/3D-rGO nanocomposite was prepared via in-situ chemical polymerization of sensitive PPy nanoparticles on the pore wall of rGO with 3D architecture. The 3D-rGO, pre-prepared by a facile hydrothermal reduction method, serves as 3D skeleton to provide solid support for sensitive PPy nanoparticles attachment. The as-formed nanocomposite displays loose 3D morphology and the fine PPy nanoparticles with high dispersion and low agglomeration distribute on the pore walls of 3D-rGO uniformly. The NH3-sensing properties of the PPy/3D-rGO nanocomposite and the single components were evaluated at room temperature. It is found that the bioinspired PPy/3D-rGO nanocomposite displays a 4–5 times enhancement in gas response compared with pure PPy and can rapidly response NH3 with sub-ppm level. It also demonstrates good dynamic characteristic, satisfactory selectivity and stability for PPy/3D-rGO nanocomposite sensor. The enhanced sensing performances of PPy/3D-rGO nanocomposite are analyzed reasonably based on its unique microstructure and the effective nanocompositeization between rGO and PPy nanoparticles.