scholarly journals Self-Assembled 1-Octadecanethiol Membrane on Pd/ZnO for a Selective Room Temperature Flexible Hydrogen Sensor

Micromachines ◽  
2021 ◽  
Vol 13 (1) ◽  
pp. 26
Author(s):  
Pawan Pathak ◽  
Hyoung Jin Cho
Keyword(s):  
Palladium Nanoparticles ◽  
Room Temperature ◽  
Low Cost ◽  
Clean Energy ◽  
Hydrogen Sensor ◽  
Sensor Response ◽  
Hydrogen Gas ◽  
Zno Nanoparticle ◽  
Energy Applications ◽  
Self Assembled

A layer of self-assembled 1-octadecanethiol was used to fabricate a palladium (Pd)/zinc oxide (ZnO) nanoparticle-based flexible hydrogen sensor with enhanced response and high selectivity at room temperature. A palladium film was first deposited using DC sputtering technique and later annealed to form palladium nanoparticles. The formation of uniform, surfactant-free palladium nanoparticles contributed to improved sensor response towards hydrogen gas at room temperature. The obtained sensor response was higher than for previously reported room temperature Pd/ZnO sensors. Furthermore, the use of the polymer membrane suppressed the sensor’s response to methane, moisture, ethanol, and acetone, resulting in the selective detection of hydrogen in the presence of the common interfering species. This study shows a viable low-cost fabrication pathway for highly selective room temperature flexible hydrogen sensors for hydrogen-powered vehicles and other clean energy applications.

scholarly journals Thin Film Gas Sensors Based on Planetary Ball-Milled Zinc Oxide Nanoinks: Effect of Milling Parameters on Sensing Performance

2021 ◽  
Vol 11 (20) ◽  
pp. 9676
Author(s):  
Raju Sapkota ◽  
Pengjun Duan ◽  
Tanay Kumar ◽  
Anusha Venkataraman ◽  
Chris Papadopoulos
Keyword(s):  
Thin Film ◽  
Zinc Oxide ◽  
Gas Sensors ◽  
Zno Nanoparticles ◽  
Food Packaging ◽  
Room Temperature ◽  
Industrial Applications ◽  
Sensor Response ◽  
Particle Sizes ◽  
Zno Nanoparticle

Planetary ball-milled zinc oxide (ZnO) nanoparticle suspensions (nanoinks) were used to produce thin film chemiresistive gas sensors that operate at room temperature. By varying milling or grinding parameters (speed, time, and solvent) different thin film gas sensors with tunable particle sizes and porosity were fabricated and tested with dry air/oxygen against hydrogen, argon, and methane target species, in addition to relative humidity, under ambient light conditions. Grinding speeds of up to 1000 rpm produced particle sizes and RMS thin film roughness below 100 nm, as measured by atomic force and scanning electron microscopy. Raman spectroscopy, photoluminescence, and X-ray analysis confirmed the purity and structure of the resulting ZnO nanoparticles. Gas sensor response at room temperature was found to peak for nanoinks milled at 400 rpm and for 30 min in ethylene glycol and deionized water, which could be correlated to an increased film porosity and enhanced variation in electron concentration resulting from adsorption/desorption of oxygen ions on the surfaces of ZnO nanoparticles. Sensor response and dynamic behavior was found to improve as the temperature was increased, peaking between 100 and 150 °C. This work demonstrates the use of low-cost PBM nanoinks as the active materials for solution-processed thin film gas/humidity sensors for use in environmental, medical, food packaging, laboratory, and industrial applications.

scholarly journals Palladium thin films for plasmonic hydrogen gas sensing

2019 ◽  
Vol 11 (2) ◽  
pp. 56
Author(s):  
Erwin Maciak
Keyword(s):  
Thin Films ◽  
Surface Plasmon Resonance ◽  
Low Temperature ◽  
Gas Sensor ◽  
Room Temperature ◽  
Fiber Optic ◽  
Hydrogen Sensor ◽  
Hydrogen Gas ◽  
Sensors And Actuators ◽  
Hydrogen Sensing

In this study, I prepared BK7 glass slides coated by palladium (Pd) layer by PVD technique. These samples have been employed as plasmon active structures in classic Kretschmann-based SPR set-up. The application of H2 sensing structures based on palladium plasmonic active thin films have been tested and investigated. Hydrogen sensing properties of Pd films were investigated at room temperature The reflectances of p-polarized light from Pd thin films as a function of angle of incidence and wavelength were measured in synthetic air (or nitrogen) and in gas mixtures including hydrogen. Variations of the reflectance in the presence of hydrogen gas at room temperature revealed that the samples can sense hydrogen in a wide range of concentration (0–2% vol/vol) without saturation behavior. The dynamic properties with various concentration of H2 at low temperature and dry gas mixtures was investigated and the effects of these factors on the hydrogen sensing properties were analyzed. Full Text: PDF ReferencesG. Korotcenkov, Handbook of Gas Sensor Materials: Properties, Advantages, and Shortcomings for Applications (Springer, New York 2013). CrossRef W. Jakubik, M. Urbanczyk, E. Maciak, "SAW hydrogen gas sensor based on WO3 and Pd nanostructures", Procedia Chemistry 1 (1), 200 (2009). CrossRef W. Jakubik, M. Urbanczyk, E. Maciak, T. Pustelny, "Bilayer Structures of NiOx and Pd in Surface Acoustic Wave and Electrical Gas Sensor Systems", Acta Physica Polonica A 116(3), 315 (2009). CrossRef E. Maciak, Z. Opilski, "Pd/V2O5 fiber optic hydrogen gas sensor", J. Phys. France IV 129, 137 (2005). CrossRef E. Maciak,. "Fiber optic sensor for H2 gas detection in the presence of methane based on Pd/WO3 low-coherence interferometric structure", Proc. SPIE 10455, UNSP 104550W (2017). CrossRef X. Bevenot, A. Truillet, C. Veillas, H. Gagnaire, M. Clement, "Hydrogen leak detection using an optical fibre sensor for aerospace applications", Sens. Actuators B 67, 57 (2000). CrossRef J. Homola, S.S. Yee, G. Gauglitz, "Surface plasmon resonance sensors: review", Sensors and Actuators B 54, 3 (1999). CrossRef H. Raether, Surface plasmons on smooth and rough surfaces and on gratings (Springer-Verlag, Berlin-Heidelberg 1988). CrossRef P. Tobiska, O. Hugon, A. Trouillet, H.Gagnarie, "An integrated optic hydrogen sensor based on SPR on palladium", Sensors and Actuators, B 74, 168 (2001). CrossRef Z. Opilski, E. Maciak, "Optical hydrogen sensor employing the phenomenon of the surface plasmons resonance in the palladium layer", Proc. SPIE 5576, 202 (2004). CrossRef T. Pustelny, E. Maciak, Z. Opilski, A. Piotrowska, E. Papis, K. Golaszewska, "Investigation of the ZnO sensing structure on NH3 action by means of the surface plasmon resonance method", European Physical Journal-Special Topics 154, 165 (2008). CrossRef E. Maciak, M. Procek, K. Kępska, A. Stolarczyk, "Study of optical and electrical properties of thin films of the conducting comb-like graft copolymer of polymethylsiloxane with poly(3-hexyltiophene) and poly(ethylene) glycol side chains for low temperature NO2 sensing", Thin Solid Films 618, 277 (2016). CrossRef

scholarly journals Reversible Room Temperature H2 Gas Sensing Based on Self-Assembled Cobalt Oxysulfide

Sensors ◽  
2021 ◽  
Vol 22 (1) ◽  
pp. 303
Author(s):  
Hui Zhou ◽  
Kai Xu ◽  
Nam Ha ◽  
Yinfen Cheng ◽  
Rui Ou ◽  
...  
Keyword(s):  
Room Temperature ◽  
Elevated Temperatures ◽  
Gas Sensing ◽  
Low Cost ◽  
High Sensitivity ◽  
Cobalt Sulfide ◽  
Bandgap Energy ◽  
Gas Molecules ◽  
Self Assembled ◽  
P Type

Reversible H2 gas sensing at room temperature has been highly desirable given the booming of the Internet of Things (IoT), zero-emission vehicles, and fuel cell technologies. Conventional metal oxide-based semiconducting gas sensors have been considered as suitable candidates given their low-cost, high sensitivity, and long stability. However, the dominant sensing mechanism is based on the chemisorption of gas molecules which requires elevated temperatures to activate the catalytic reaction of target gas molecules with chemisorbed O, leaving the drawbacks of high-power consumption and poor selectivity. In this work, we introduce an alternative candidate of cobalt oxysulfide derived from the calcination of self-assembled cobalt sulfide micro-cages. It is found that the majority of S atoms are replaced by O in cobalt oxysulfide, transforming the crystal structure to tetragonal coordination and slightly expanding the optical bandgap energy. The H2 gas sensing performances of cobalt oxysulfide are fully reversible at room temperature, demonstrating peculiar p-type gas responses with a magnitude of 15% for 1% H2 and a high degree of selectivity over CH4, NO2, and CO2. Such excellent performances are possibly ascribed to the physisorption dominating the gas–matter interaction. This work demonstrates the great potentials of transition metal oxysulfide compounds for room-temperature fully reversible gas sensing.

scholarly journals Effective hydrogen gas sensor based on palladium nanoparticles dispersed on graphene sheets by spin coating technique

2020 ◽  
Vol 38 (2) ◽  
pp. 305-311
Author(s):  
Saowaluk Inpaeng ◽  
Worawut Muangrat ◽  
Karaked Tedsree ◽  
Wolfgang Pfeiler ◽  
Thanawee Chodjarusawad ◽  
...  
Keyword(s):  
Spin Coating ◽  
Palladium Nanoparticles ◽  
Room Temperature ◽  
Effective Means ◽  
Hydrogen Gas ◽  
Spin Coating Technique ◽  
Graphene Sheets ◽  
Adsorption Model ◽  
Coating Technique ◽  
Vapor Deposition Technique

AbstractA room-temperature hydrogen gas (H2) sensor was successfully fabricated by dispersion of palladium nanoparticles (Pd NPs) on graphene sheets (GRs) (hereafter referred to as “Pd NPs/GRs”). GRs and Pd NPs were synthesized by chemical vapor deposition technique and by polyol process, respectively. A colloidal solution of Pd NPs with an average diameter of 11 nm was then dispersed onto the GRs by spin coating technique. The density of dispersed Pd NPs on GRs was controlled by varying the volume of the dispersed solution within the range of 50 – 150 μL. The fabricated Pd NPs/GRs sensors exhibited a high sensitivity for H2 gas with a concentration of 1500 – 6000 ppm at room temperature. Upon H2 exposure, the Pd NPs/GRs sensors showed an increase in electrical resistance, which could easily be measured. The relationship between sensor response and H2 concentration is in correspondence with the Langmuir adsorption model. The H2 detection limit is estimated to be 1 ppm. The results demonstrate that the Pd NPs/GRs sensor is an easily fabricated, but very effective means for room-temperature detection of H2at ppm level.

scholarly journals Atomically dispersed Pb ionic sites in PbCdSe quantum dot gels enhance room-temperature NO2 sensing

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Xin Geng ◽  
Shuwei Li ◽  
Lalani Mawella-Vithanage ◽  
Tao Ma ◽  
Mohamed Kilani ◽  
...  
Keyword(s):  
Quantum Dot ◽  
Metal Ion ◽  
High Performance ◽  
Room Temperature ◽  
Limit Of Detection ◽  
Theoretical Calculations ◽  
Low Cost ◽  
High Sensitivity ◽  
Sensor Response ◽  
Response And Recovery

AbstractAtmospheric NO2 is of great concern due to its adverse effects on human health and the environment, motivating research on NO2 detection and remediation. Existing low-cost room-temperature NO2 sensors often suffer from low sensitivity at the ppb level or long recovery times, reflecting the trade-off between sensor response and recovery time. Here, we report an atomically dispersed metal ion strategy to address it. We discover that bimetallic PbCdSe quantum dot (QD) gels containing atomically dispersed Pb ionic sites achieve the optimal combination of strong sensor response and fast recovery, leading to a high-performance room-temperature p-type semiconductor NO2 sensor as characterized by a combination of ultra–low limit of detection, high sensitivity and stability, fast response and recovery. With the help of theoretical calculations, we reveal the high performance of the PbCdSe QD gel arises from the unique tuning effects of Pb ionic sites on NO2 binding at their neighboring Cd sites.

Sign in / Sign up

Export Citation Format

Share Document