Simple Synthesis of Cobalt Carbonate Hydroxide Hydrate and Reduced Graphene Oxide Hybrid Structure for High-Performance Room Temperature NH3 Sensor

A novel hybrid structure sensor based on cobalt carbonate hydroxide hydrate (CCHH) and reduced graphene oxide (RGO) was designed for room temperature NH3 detection. This hybrid structure consisted of CCHH and RGO (synthesized by a one-step hydrothermal method), in which RGO uniformly dispersed in CCHH, being used as the gas sensing film. The resistivity of the hybrid structure was highly sensitive to the changes on NH3 concentration. CCHH in the hybrid structure was the sensing material and RGO was the conductive channel material. The hybrid structure could improve signal-to-noise ratio (SNR) and the sensitivity by obtaining the optimal mass proportion of RGO, since the proportion of RGO was directly related to sensitivity. The gas sensor with 0.4 wt% RGO showed the highest gas sensing response reach to 9% to 1 ppm NH3. Compared to a conventional gas sensor, the proposed sensor not only showed high gas sensing response at room temperature but also was easy to achieve large-scale production due to the good stability and simple synthesis process.

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Ammonia Gas Detection by Tannic Acid Functionalized and Reduced Graphene Oxide at Room Temperature

Journal of Nanomaterials ◽

10.1155/2014/497384 ◽

2014 ◽

Vol 2014 ◽

pp. 1-6 ◽

Cited By ~ 40

Author(s):

Sweejiang Yoo ◽

Xin Li ◽

Yuan Wu ◽

Weihua Liu ◽

Xiaoli Wang ◽

...

Keyword(s):

Graphene Oxide ◽

Reduced Graphene Oxide ◽

Gas Sensor ◽

Tannic Acid ◽

Room Temperature ◽

Gas Sensing ◽

High Sensitivity ◽

Gas Detection ◽

Ammonia Gas ◽

Reduced Graphene

Reduced graphene oxide (rGO) based chemiresistor gas sensor has received much attention in gas sensing for high sensitivity, room temperature operation, and reversible. Here, for the first time, we present a promising chemiresistor for ammonia gas detection based on tannic acid (TA) functionalized and reduced graphene oxide (rGOTA functionalized). Green reductant of TA plays a major role in both reducing process and enhancing the gas sensing properties ofrGOTA functionalized. Our results showrGOTA functionalizedonly selective to ammonia with excellent respond, recovery, respond time, and recovery times.rGOTA functionalizedelectrical resistance decreases upon exposure to NH3where we postulated that it is due to n-doping by TA and charge transfer betweenrGOTA functionalizedand NH3through hydrogen bonding. Furthermore,rGOTA functionalizedhinders the needs for stimulus for both recovery and respond. The combination of greener sensing material and simplicity in overall sensor design provides a new sight for green reductant approach of rGO based chemiresistor gas sensor.

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A high-sensitive room temperature gas sensor based on cobalt phthalocyanines and reduced graphene oxide nanohybrids for the ppb-levels of ammonia detection

RSC Advances ◽

10.1039/c9ra08065a ◽

2019 ◽

Vol 9 (64) ◽

pp. 37518-37525 ◽

Cited By ~ 4

Author(s):

ZhiJiang Guo ◽

Bin Wang ◽

Xiaolin Wang ◽

Yong Li ◽

Shijie Gai ◽

...

Keyword(s):

Graphene Oxide ◽

Environmental Pollution ◽

Reduced Graphene Oxide ◽

Gas Sensor ◽

Room Temperature ◽

Gas Sensing ◽

Pollution Monitoring ◽

Reduced Graphene ◽

Highly Sensitive ◽

Ammonia Detection

Highly sensitive gas sensing materials are of great importance for environmental pollution monitoring.

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Highly sensitive and selective room-temperature NO2 gas sensor based on novel Fe2O3 nanorings/reduced graphene oxide heterojunction nanocomposites

Optik ◽

10.1016/j.ijleo.2021.166951 ◽

2021 ◽

pp. 166951

Author(s):

Xiaoshan Tang ◽

Canxin Tian ◽

Changwei Zou

Keyword(s):

Graphene Oxide ◽

Reduced Graphene Oxide ◽

Gas Sensor ◽

Room Temperature ◽

No2 Gas Sensor ◽

Reduced Graphene ◽

Highly Sensitive

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Functionalized Reduced Graphene Oxide Thin Films for Ultrahigh CO2 Gas Sensing Performance at Room Temperature

Nanomaterials ◽

10.3390/nano11030623 ◽

2021 ◽

Vol 11 (3) ◽

pp. 623

Author(s):

Monika Gupta ◽

Huzein Fahmi Hawari ◽

Pradeep Kumar ◽

Zainal Arif Burhanudin ◽

Nelson Tansu

Keyword(s):

Thin Films ◽

Graphene Oxide ◽

Reduced Graphene Oxide ◽

Gas Sensor ◽

Functional Groups ◽

Recovery Time ◽

Room Temperature ◽

Co2 Gas ◽

Reduced Graphene ◽

Response And Recovery

The demand for carbon dioxide (CO2) gas detection is increasing nowadays. However, its fast detection at room temperature (RT) is a major challenge. Graphene is found to be the most promising sensing material for RT detection, owing to its high surface area and electrical conductivity. In this work, we report a highly edge functionalized chemically synthesized reduced graphene oxide (rGO) thin films to achieve fast sensing response for CO2 gas at room temperature. The high amount of edge functional groups is prominent for the sorption of CO2 molecules. Initially, rGO is synthesized by reduction of GO using ascorbic acid (AA) as a reducing agent. Three different concentrations of rGO are prepared using three AA concentrations (25, 50, and 100 mg) to optimize the material properties such as functional groups and conductivity. Thin films of three different AA reduced rGO suspensions (AArGO25, AArGO50, AArGO100) are developed and later analyzed using standard FTIR, XRD, Raman, XPS, TEM, SEM, and four-point probe measurement techniques. We find that the highest edge functionality is achieved by the AArGO25 sample with a conductivity of ~1389 S/cm. The functionalized AArGO25 gas sensor shows recordable high sensing properties (response and recovery time) with good repeatability for CO2 at room temperature at 500 ppm and 50 ppm. Short response and recovery time of ~26 s and ~10 s, respectively, are achieved for 500 ppm CO2 gas with the sensitivity of ~50 Hz/µg. We believe that a highly functionalized AArGO CO2 gas sensor could be applicable for enhanced oil recovery, industrial and domestic safety applications.

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