Heterostructures of polyaniline@SnO2 loading on flexible PET thin films for triethylamine detection at room temperature

Abstract

A p–n heterostructure hybrid based on polyaniline–SnO₂ was synthesized by a rapid and facile in situ chemical oxidation polymerization at very low monomer concentration, and the hybrid was loaded on a flexible polyethylene terephthalate (PET) film substrate to structure a smart triethylamine (TEA) sensor. The structure, morphology and composition of the hybrid have been characterized by various analysis methods. The sensor not only exhibits high sensitivity, good selectivity to some other volatile organic compounds and wide linear response to 10–100 ppm triethylamine (TEA) at room temperature but is also flexible, has a simple structure and wearable performance. The mechanism of enhanced gas sensing is discussed in detail, which is attributed to the thickening of the depletion layer due to the formation of a p–n heterojunction at an interface in the hybrid. The research is expected to open a new window for the development of a kind of portable and wearable electronic device based on various p–n heterostructure hybrids.