A 3D Chemically Modified Graphene Hydrogel for Fast, Highly Sensitive, and Selective Gas Sensor.
Reduced graphene oxide (RGO) has proved to be a promising candidate in high-performance gas sensing in ambient conditions. However, trace detection of different kinds of gases with simultaneously high sensitivity and selectivity is challenging. Here, a chemiresistor-type sensor based on 3D sulfonated RGO hydrogel (S-RGOH) is reported, which can detect a variety of important gases with high sensitivity, boosted selectivity, fast response, and good reversibility. The NaHSO3functionalized RGOH displays remarkable 118.6 and 58.9 times higher responses to NO2and NH3, respectively, compared with its unmodified RGOH counterpart. In addition, the S-RGOH sensor is highly responsive to volatile organic compounds. More importantly, the characteristic patterns on the linearly fitted response-temperature curves are employed to distinguish various gases for the first time. The temperature of the sensor is elevated rapidly by an imbedded microheater with little power consumption. The 3D S-RGOH is characterized and the sensing mechanisms are proposed. This work gains new insights into boosting the sensitivity of detecting various gases by combining chemical modification and 3D structural engineering of RGO, and improving the selectivity of gas sensing by employing temperature dependent response characteristics of RGO for different gases.
School of Mechanical and Aerospace Engineering Nanyang Technological University Singapore 639798 Singapore.
Jin
J
Wu
School of Mechanical and Aerospace Engineering Nanyang Technological University Singapore 639798 Singapore.
Kai
K
Tao
School of Materials Science and Engineering Nanyang Technological University 50 Nanyang Avenue Singapore 639798 Singapore.
Yuanyuan
Y
Guo
School of Mechanical and Aerospace Engineering Nanyang Technological University Singapore 639798 Singapore.
Zhong
Z
Li
School of Materials Science and Engineering Nanyang Technological University 50 Nanyang Avenue Singapore 639798 Singapore.
Xiaotian
X
Wang
School of Materials Science and Engineering Nanyang Technological University 50 Nanyang Avenue Singapore 639798 Singapore.
Zhongzhen
Z
Luo
Micro-Nano Manufacturing and System Integration Center Chongqing Institute of Green and Intelligent Technology Chinese Academy of Sciences Chongqing 400714 P. R. China.
Shuanglong
S
Feng
Micro-Nano Manufacturing and System Integration Center Chongqing Institute of Green and Intelligent Technology Chinese Academy of Sciences Chongqing 400714 P. R. China.
Chunlei
C
Du
Key Laboratory for Thin Film and Microfabrication Technology of Ministry of Education Department of Instrument Science and Engineering School of Electronic Information and Electrical Engineering Shanghai Jiao Tong University 800 Dongchuan Road Shanghai 200240 P. R. China; Shanghai Engineering Research Center for Intelligent Diagnosis and Treatment Instrument 800 Dongchuan Road Shanghai 200240 P. R. China.
Di
D
Chen
School of Mechanical and Aerospace Engineering Nanyang Technological University Singapore 639798 Singapore.
Jianmin
J
Miao
Center for Environmental Sensing and Modeling (CENSAM) Singapore-MIT Alliance for Research and Technology (SMART) Centre Singapore 117543 Singapore; Department of Architecture Massachusetts Institute of Technology Cambridge MA 02139 USA.
Leslie K
LK
Norford
3D reduced graphene oxide hydrogel; chemical modification; gas sensor; microheater; sulfonated