TY - JOUR
T1 - The quest for highly sensitive QCM humidity sensors
T2 - The coating of CNT/MOF composite sensing films as case study
AU - Chappanda, Karumbaiah N.
AU - Shekhah, Osama
AU - Yassine, Omar
AU - Patole, Shashikant P.
AU - Eddaoudi, Mohamed
AU - Salama, Khaled N.
N1 - Funding Information:
This work was partially sponsored by the Advanced Membranes and Porous Materials Center (AMPMC)’s grant FCC/1/1972-05-01 within the “Stimuli Responsive Materials” thrust. We thank Ulrich Buttner of ‘Microfluidic Lab, part of the Nanofabrication Core Lab’, for providing his assistance in the project. Karumbaiah N. Chappanda is a post-doctoral fellow in Computer, Electrical and Mathematical Sciences and Engineering Division at King Abduallah University of Science and Technology. His research interest include gas sensors, device fabrication and nano-lithography. Osama Shekhah is a research scientist in Physical Sciences and Engineering Division at King Abdullah University of Science and Technology. His research interest include surface chemistry, material chemistry, thin films, and porous materials. Omar Yassine is a research scientist in Computer, Electrical and Mathematical Sciences and Engineering Division at King Abduallah University of Science and Technology. His research interest include gas sensors and Microfluidics. Shashikant P. Patole is a post-doctoral fellow in Computer, Electrical and Mathematical Sciences and Engineering Division at King Abduallah University of Science and Technology. His research interest include synthesis, characterization and applications of SP2 hybridized carbon materials. Mohamed Eddaoudi is a professor in Physical Sciences and Engineering Division at King Abdullah University of Science and Technology. He is also the director of Advanced Membranes and Porous Materials Research Center at King Abdullah University of Science and Technology. Khaled Nabil Salama is an Associate Professor and founding chair member in the Electrical engineering department at King Abduallah University of Science and Technology. His research interests include electronic circuit design and semiconductors' fabrication.
Publisher Copyright:
© 2017 Elsevier B.V.
PY - 2018/3
Y1 - 2018/3
N2 - The application of metal-organic frameworks (MOFs) as a sensing layer has been attracting great interest over the last decade, due to their uniform properties in terms of high porosity and tunability, which provides a large surface area and/or centers for trapping/binding a targeted analyte. Here we report the fabrication of a highly sensitive humidity sensor that is based on composite thin films of HKUST-1 MOF and carbon nanotubes (CNT). The composite sensing films were fabricated by spin coating technique on a quartz-crystal microbalance (QCM) and a comparison of their shift in resonance frequencies to adsorbed water vapor (5–75% relative humidity) is presented. Through optimization of the CNT and HKUST-1 composition, we could demonstrate a 230% increase in sensitivity compared to plain HKUST-1 film. The optimized CNT-HKUST-1 composite thin films are stable, reliable, and have an average sensitivity of about 2.5 × 10−5 (Δf/f) per percent of relative humidity, which is up to ten times better than previously reported QCM-based humidity sensors. The approach presented here is facile and paves a promising path towards enhancing the sensitivity of MOF-based sensors.
AB - The application of metal-organic frameworks (MOFs) as a sensing layer has been attracting great interest over the last decade, due to their uniform properties in terms of high porosity and tunability, which provides a large surface area and/or centers for trapping/binding a targeted analyte. Here we report the fabrication of a highly sensitive humidity sensor that is based on composite thin films of HKUST-1 MOF and carbon nanotubes (CNT). The composite sensing films were fabricated by spin coating technique on a quartz-crystal microbalance (QCM) and a comparison of their shift in resonance frequencies to adsorbed water vapor (5–75% relative humidity) is presented. Through optimization of the CNT and HKUST-1 composition, we could demonstrate a 230% increase in sensitivity compared to plain HKUST-1 film. The optimized CNT-HKUST-1 composite thin films are stable, reliable, and have an average sensitivity of about 2.5 × 10−5 (Δf/f) per percent of relative humidity, which is up to ten times better than previously reported QCM-based humidity sensors. The approach presented here is facile and paves a promising path towards enhancing the sensitivity of MOF-based sensors.
KW - CNT
KW - Composites
KW - Humidity
KW - Metal-organic frameworks
KW - Sensors
UR - http://www.scopus.com/inward/record.url?scp=85032906952&partnerID=8YFLogxK
U2 - 10.1016/j.snb.2017.10.189
DO - 10.1016/j.snb.2017.10.189
M3 - Article
AN - SCOPUS:85032906952
SN - 0925-4005
VL - 257
SP - 609
EP - 619
JO - Sensors and Actuators, B: Chemical
JF - Sensors and Actuators, B: Chemical
ER -