Indigenous carbon humidity sensor for radiosondes

Combined photoluminescence and impedance spectroscopy studies show that a europium-based metal–organic framework behaves as a highly effective and reliable humidity sensor, enabling dual-mode humidity detection.

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High-performance humidity sensors from Ni(SO4)0.3(OH)1.4 nanobelts

Nanoscale ◽

10.1039/c4nr00277f ◽

2014 ◽

Vol 6 (12) ◽

pp. 6521-6525 ◽

Cited By ~ 7

Author(s):

Ming Zhuo ◽

Yuejiao Chen ◽

Tao Fu ◽

Haonan Zhang ◽

Zhi Xu ◽

...

Keyword(s):

High Performance ◽

Humidity Sensor ◽

High Sensitivity ◽

Fast Response ◽

Humidity Sensors ◽

Term Stability ◽

Long Term Stability

Ni(SO4)0.3(OH)1.4 nanobelts are utilized in a humidity sensor by a facile method. The nanobelt based sensor shows a high sensitivity, fast response and long-term stability in the sensing process.

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Evaluation of radiosonde humidity sensors at low temperature using ultralow-temperature humidity chamber

Advances in Science and Research ◽

10.5194/asr-15-207-2018 ◽

2018 ◽

Vol 15 ◽

pp. 207-212 ◽

Cited By ~ 5

Author(s):

Byung Il Choi ◽

Sang-Wook Lee ◽

Sang-Bong Woo ◽

Jong Chul Kim ◽

Yong-Gyoo Kim ◽

...

Keyword(s):

Water Vapor ◽

Low Temperature ◽

Response Time ◽

Humidity Sensor ◽

Weather Prediction ◽

Observation Data ◽

Humidity Sensors ◽

Ultralow Temperature ◽

Humidity Chamber ◽

Sensing Characteristics

Abstract. Accurate measurements of temperature and water vapor in the upper-air are of great interest in relation to weather prediction and climate change. Those measurements are mostly conducted using radiosondes equipped with a variety of sensors that are flown by a balloon up to lower stratosphere. Reference Upper Air Network (GRUAN) has identified water vapor pressure as one of the most important measurands and has set an accuracy requirement of 2 % in terms of the mixing ratio. In order to achieve the requirement, many errors in the humidity measurement such as a temperature dependency in sensing characteristics including measurement values and response time need to be corrected because humidity sensors of radiosondes pass through low-pressure (1 kPa) and low-temperature (−80 ∘C) environments in the upper-air. In this paper, the humidity sensing characteristics of Jinyang radiosonde sensors in relation to temperature dependencies were evaluated at low temperature using a newly developed ultralow-temperature humidity chamber. The sensitivity characteristic curve of the radiosonde sensors was evaluated down to −80 ∘C, and the calibration curves of the humidity sensor and the temperature sensor were obtained. The response time of humidity sensor slowly increased from 52 to 116 s at the temperature from 20 to −40 ∘C, respectively, and then rapidly increased to almost one hour at −80 ∘C. Those results will help to improve the reliability of the upper-air observation data.

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Proton transport over nanoparticle surface in insulating nanoparticle film-based humidity sensor

Japanese Journal of Applied Physics ◽

10.35848/1347-4065/ac4b0e ◽

2022 ◽

Author(s):

Shinya Kano ◽

Harutaka MEKARU

Keyword(s):

Activation Energy ◽

Proton Transfer ◽

Proton Transport ◽

Humidity Sensor ◽

Silica Nanoparticle ◽

Humidity Sensors ◽

Nanoparticle Surface ◽

Transfer Mechanisms ◽

Hydrophobic Ligand ◽

Nanoparticle Film

Abstract We study a proton transport on the surface of insulating nanoparticles for humidity sensors. We use the approach to reveal proton transfer mechanisms in humidity sensitive materials. Hydrophilic and hydrophobic ligand-terminated silica nanoparticle films are adopted for evaluating temperature dependence of the ion conductivity. According to the activation energy of the conductivity, we explain the Grotthuss (H+ transfer) and vehicular (H3O+ transfer) mechanisms are mainly dominant on hydrophilic (-OH terminated) and hydrophobic (acrylate terminated) surface of nanoparticles, respectively. This investigation gives us a clue to understand a proton transfer mechanism in solution-processed humidity-sensitive materials such as oxide nanomaterials.

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Fabrication of bulk alumina structures with humidity sensing capabilities using direct ink write technique

Rapid Prototyping Journal ◽

10.1108/rpj-12-2019-0322 ◽

2021 ◽

Vol ahead-of-print (ahead-of-print) ◽

Author(s):

Anabel Renteria ◽

Luisa F. Garcia ◽

Jorge A. Diaz ◽

Luis C. Delfin ◽

Jaime E. Regis ◽

...

Keyword(s):

Humidity Sensor ◽

Post Processing ◽

Humidity Sensors ◽

Moisture Sensitivity ◽

Humidity Sensing ◽

Content Type ◽

Lattice Design ◽

Processing Treatment ◽

Binder Ratio ◽

Order Of Magnitude

Purpose The purpose of this study is to evaluate different 3D structures for humidity sensing that will enable the fabrication of complex geometries with high moisture sensitivity. Design/methodology/approach Humidity sensors based on alumina ceramics were fabricated using direct ink write (DIW) technique. Different engineered surface area, polymer binder ratio and post-processing treatment were considered to increase moisture sensitivity. Findings It was found that the binder ratio plays an important role in controlling the rheology of the paste during printing and determining the pore size after post-processing treatment. The sensibility of the fabricated humidity sensor was investigated by measuring its capacitance response toward relative humidity (RH) varying from 40% to 90% RH at 25°C. It is shown that using 3D lattice design, printed alumina humidity sensor could improve sensitivity up to 31.6 pF/RH%, over an order of magnitude higher than solid alumina. Originality/value Most of the alumina humidity sensors available are films in nature because of manufacturing difficulties, which limited its potential of higher sensitivity, and thus broader applications. In this paper, a novel 3D alumina humidity sensor was fabricated using DIW 3D printing technology.

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Paper-Based ZnS:Cu Alternating Current Electroluminescent Devices for Current Humidity Sensors with High–Linearity and Flexibility

Sensors ◽

10.3390/s19214607 ◽

2019 ◽

Vol 19 (21) ◽

pp. 4607 ◽

Cited By ~ 3

Author(s):

Yaqin He ◽

Mengyao Zhang ◽

Nan Zhang ◽

Danrong Zhu ◽

Chun Huang ◽

...

Keyword(s):

Humidity Sensor ◽

Silver Nanowires ◽

Alternating Current ◽

Sensor Technology ◽

Sensing Element ◽

Humidity Sensors ◽

Phosphor Layer ◽

Humidity Sensing ◽

Electroluminescent Devices ◽

Sensing Mechanism

Humidity sensors are indispensable for various electronic systems and instrumentations. To develop a new humidity sensing mechanism is the key for the next generation of sensor technology. In this work, a novel flexible paper-based current humidity sensor is proposed. The developed alternating current electroluminescent devices (ACEL) consist of the electroless plating Ni on filter paper and silver nanowires (AgNWs) as the bottom and upper electrodes, and ZnS:Cu as the phosphor layer, respectively. The proposed humidity sensor is based on ACEL with the paper substrate and the ZnS:Cu phosphor layer as the humidity sensing element. The moisture effect on the optical properties of ACELs has been studied firstly. Then, the processing parameters of the paper-based ACELs such as electroless plated bottom electrode and spin-coated phosphor layer as a function of the humidity-sensitive characteristics are investigated. The sensing mechanism of the proposed sensor has been elucidated based on the Q ~ V analysis. The sensor exhibits an excellent linearity ( R 2 = 0.99965 ) within the humidity range from 20% to 90% relative humidity (RH) and shows excellent flexibility. We also demonstrate its potential application in postharvest preservation where the EL light is used for preservation and the humidity can be monitored simultaneously through the current.

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Fast-response ionogel humidity sensor for real-time monitoring of breathing rate

Materials Chemistry Frontiers ◽

10.1039/c8qm00596f ◽

2019 ◽

Vol 3 (3) ◽

pp. 484-491 ◽

Cited By ~ 9

Author(s):

Songhua Xiao ◽

Jianxia Nie ◽

Rou Tan ◽

Xiaochuan Duan ◽

Jianmin Ma ◽

...

Keyword(s):

Ionic Liquids ◽

Real Time ◽

Humidity Sensor ◽

Fast Response ◽

Breathing Rate ◽

Real Time Monitoring ◽

Silica Network ◽

Humidity Sensors ◽

Human Breath

Ionogel-based chemoresistive humidity sensors have been successfully fabricated through ionothermal assembly of ionic liquids into a silica network, which exhibited superior humidity performances. Fast substantial impedance changes were observed with changing humidity for real-time monitoring of human breath.

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Highly chemoresistive humidity sensing using poly(ionic liquid)s

Chemical Communications ◽

10.1039/c6cc04056j ◽

2016 ◽

Vol 52 (54) ◽

pp. 8417-8419 ◽

Cited By ~ 26

Author(s):

Lingling Wang ◽

Xiaochuan Duan ◽

Wuyuan Xie ◽

Qiuhong Li ◽

Taihong Wang

Keyword(s):

Ionic Liquid ◽

Relative Humidity ◽

High Performance ◽

Humidity Sensor ◽

High Sensitivity ◽

Fast Response ◽

Humidity Sensors ◽

Humidity Sensing ◽

Good Repeatability ◽

Poly Ionic Liquid

A novel resistance type humidity sensor was fabricated using poly(ionic liquid)s, which exhibited high sensitivity, fast response, small hysteresis and good repeatability at a relative humidity (RH) in the range of 11–98%, making poly(ionic liquid)s as promising sensing materials for high-performance humidity sensors.

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