Sulfophenyl-Functionalized Reduced Graphene Oxide Networks on Electrospun 3D Scaffold for Ultrasensitive NO2 Gas Sensor

Abstract

Ultrasensitive room temperature real-time NO2 sensors are highly desirable due to potential threats on environmental security and personal respiratory. Traditional NO2 gas sensors with highly operated temperatures (200–600 °C) and limited reversibility are mainly constructed from semiconducting oxide-deposited ceramic tubes or inter-finger probes. Herein, we report the functionalized graphene network film sensors assembled on an electrospun three-dimensional (3D) nanonetwork skeleton for ultrasensitive NO2 sensing. The functional 3D scaffold was prepared by electrospinning interconnected polyacrylonitrile (PAN) nanofibers onto a nylon window screen to provide a 3D nanonetwork skeleton. Then, the sulfophenyl-functionalized reduced graphene oxide (SFRGO) was assembled on the electrospun 3D nanonetwork skeleton to form SFRGO network films. The assembled functionalized graphene network film sensors exhibit excellent NO2 sensing performance (10 ppb to 20 ppm) at room temperature, reliable reversibility, good selectivity, and better sensing cycle stability. These improvements can be ascribed to the functionalization of graphene with electron-withdrawing sulfophenyl groups, the high surface-to-volume ratio, and the effective sensing channels from SFRGO wrapping onto the interconnected 3D scaffold. The SFRGO network-sensing film has the advantages of simple preparation, low cost, good processability, and ultrasensitive NO2 sensing, all advantages that can be utilized for potential integration into smart windows and wearable electronic devices for real-time household gas sensors.

Porous materials as effective chemiresistive gas sensors

“…Donor groups like amidogen (-NH 2 ) on organic molecules enhance electron transfer between gas molecules and graphene. 159,160 Wan et al created a flexible, transparent graphene-polyaniline (PANI) nanocomposite film for highly sensitive NH 3 detection. The wearable sensor detected NH 3 from 100 ppb to 100 ppm with a rapid response and recovery times of 36s and 18s, respectively.…”

Wearable Electrochemical Sensors Based on Nanomaterials for Healthcare Applications

“…Michael E. Smith [236] devel- ops a novel wearable vision H 2 sensor for non-invasive monitoring of biodegradation of magnesium implants in vivo in medical research and clinical Settings. The development of a real-time NO 2 sensor is also of interest [237]. Hua et al [238].…”

Reduced Graphene Oxide (rGO)-Loaded Metal-Oxide Nanofiber Gas Sensors: An Overview

“…The following section explains the gas sensing capability of rGO-loaded metal oxide NFs. This paper does not discuss the combination of rGO with other materials, such as mesh fabric [ 53 ] or polymers [ 54 , 55 ], for gas sensing studies. Furthermore, composites of metal oxides-rGO in morphologies other than NFs are not discussed.…”