UV-light enhanced CO gas sensors based on InGaN nanorods decorated with p-Phenylenediamine-graphene oxide composite

Abstract Coupling of graphene and its derivatives with organic moieties is one of the promising strategies to enhance the gas sensing performance. A novel ternary nanocomposite of p-Phenylenediamine-graphene oxide (PGO)/InGaN nanorods (NRs) probed as chemiresistive gas sensor for carbon monoxide (CO) in ppm concentrations. The InGaN NRs were grown by molecular beam epitaxy, and a drop-casting method was employed to decorate the PGO composite on InGaN NRs. The sensor devices consisting of PGO/InGaN NRs with interdigitated electrodes have been fabricated, and their sensing characteristics for CO were studied. PGO composite provided a significant decrease in the electrical resistance of the ternary nanocomposite of PGO/InGaN at the operating temperature (27 °C – 100 °C). The sensor device based on PGO/InGaN NRs exhibited a higher response than the GO/InGaN NRs. The PGO/InGaN NRs device exhibited a maximum sensing response of ∼131 % at a CO concentration of 100 ppm at an operation temperature of 100 °C, which is 2.7 times higher than the GO/InGaN NRs sensor response. Also, the response (∼93.58%) was remarkably improved under UV illumination at room temperature. The combined effect of active cites in GO and the increased electron density at the nitrogen atom in the amine groups of the PGO are responsible for the excellent performance