Chemiresistive gas sensor for the sensitive detection of nitrogen dioxide based on nitrogen doped graphene nanosheets

N-containing gaseous compounds, such as trimethylamine (TMA), triethylamine (TEA), ammonia (NH3), nitrogen monoxide (NO), and nitrogen dioxide (NO2) exude irritating odors and are harmful to the human respiratory system at high concentrations. In this study, we investigated the sensing responses of five sensor materials—Al-doped ZnO (AZO) nanoparticles (NPs), Pt-loaded AZO NPs, a Pt-loaded WO3 (Pt-WO3) thin film, an Au-loaded WO3 (Au-WO3) thin film, and N-doped graphene—to the five aforementioned gases at a concentration of 10 parts per million (ppm). The ZnO- and WO3-based materials exhibited n-type semiconducting behavior, and their responses to tertiary amines were significantly higher than those of nitric oxides. The N-doped graphene exhibited p-type semiconducting behavior and responded only to nitric oxides. The Au- and Pt-WO3 thin films exhibited extremely high responses of approximately 100,000 for 10 ppm of triethylamine (TEA) and approximately −2700 for 10 ppm of NO2, respectively. These sensing responses are superior to those of previously reported sensors based on semiconducting metal oxides. On the basis of the sensing response results, we drew radar plots, which indicated that selective pattern recognition could be achieved by using the five sensing materials together. Thus, we demonstrated the possibility to distinguish each type of gas by applying the patterns to recognition techniques.

Section: Resultsmentioning

confidence: 97%

Selective Detection of Nitrogen-Containing Compound Gases

Yoo

Lee

Kim

et al. 2019

“…A nylon window screen film (15 cm × 15 cm, oxygen plasma pretreatment) coated on the aluminum foil was employed as the collector, which was placed 15 cm away from the syringe needle. The feeding rate of the solution was 0.5 mL/h, and the applied potential between the needle and collector was 20 KV [ 14 , 19 ]. After electrostatic spinning for different time periods, the PAN-coated nylon window screens were collected as 3D scaffolds and dried at room temperature.…”

Section: Methodsmentioning

confidence: 99%

“…Chemically modified graphene films have good sensing performances to different concentrations of NO 2 , from 15 to 115 ppm [ 18 ]. The nitrogen-doped graphene nanosheet-based sensors demonstrated a high sensing response to NO 2 , from 2.5 to 100 ppm [ 19 ]. However, there are seldom reports for ultrasensitive sensors that detect lower concentrations of NO 2 (10–200 ppb).…”

Section: Introductionmentioning

confidence: 99%

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

Zou

Guo

Shen

et al. 2017

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.

“…To experimentally confirm some of the above-mentioned theoretical predictions, various doped graphene materials have been synthesized and evaluated as toxic gas sensors [ 103 , 104 , 105 , 106 , 107 , 108 ]. Based on experimental evidence, the sensitivity and selectivity of doped graphene were higher than pristine graphene [ 103 , 104 , 105 , 106 , 107 ]. However, it is difficult to control the doping concentration and the number of graphene layers.…”

Section: Doped Graphenementioning

confidence: 99%

Recent Developments in Graphene-Based Toxic Gas Sensors: A Theoretical Overview

Cruz-Martínez

Rojas-Chávez

Montejo‐Alvaro

et al. 2021

Detecting and monitoring air-polluting gases such as carbon monoxide (CO), nitrogen oxides (NOx), and sulfur oxides (SOx) are critical, as these gases are toxic and harm the ecosystem and the human health. Therefore, it is necessary to design high-performance gas sensors for toxic gas detection. In this sense, graphene-based materials are promising for use as toxic gas sensors. In addition to experimental investigations, first-principle methods have enabled graphene-based sensor design to progress by leaps and bounds. This review presents a detailed analysis of graphene-based toxic gas sensors by using first-principle methods. The modifications made to graphene, such as decorated, defective, and doped to improve the detection of NOx, SOx, and CO toxic gases are revised and analyzed. In general, graphene decorated with transition metals, defective graphene, and doped graphene have a higher sensibility toward the toxic gases than pristine graphene. This review shows the relevance of using first-principle studies for the design of novel and efficient toxic gas sensors. The theoretical results obtained to date can greatly help experimental groups to design novel and efficient graphene-based toxic gas sensors.