scholarly journals Tin Disulfide-Coated Microfiber for Humidity Sensing with Fast Response and High Sensitivity

Crystals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 648
Author(s):  
Aijie Liang ◽  
Jingyuan Ming ◽  
Wenguo Zhu ◽  
Heyuan Guan ◽  
Xinyang Han ◽  
...  

Breath monitoring is significant in assessing human body conditions, such as cardiac and pulmonary symptoms. Optical fiber-based sensors have attracted much attention since they are immune to electromagnetic radiation, thus are safe for patients. Here, a microfiber (MF) humidity sensor is fabricated by coating tin disulfide (SnS2) nanosheets onto the surface of MF. The small diameter (~8 μm) and the long length (~5 mm) of the MF promise strong interaction between guiding light and SnS2. Thus, a small variation in the relative humidity (RH) will lead to a large change in optical transmitted power. A high RH sensitivity of 0.57 dB/%RH is therefore achieved. The response and recovery times are estimated to be 0.08 and 0.28 s, respectively. The high sensitivity and fast response speed enable our SnS2-MF sensor to monitor human breath in real time.

Nanomaterials ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1915
Author(s):  
Shenawar Ali Khan ◽  
Muhammad Saqib ◽  
Muhammad Muqeet Rehman ◽  
Hafiz Mohammad Mutee Ur Rehman ◽  
Sheik Abdur Rahman ◽  
...  

A novel composite based on a polymer (P(VDF-TrFE)) and a two-dimensional material (graphene flower) was proposed as the active layer of an interdigitated electrode (IDEs) based humidity sensor. Silver (Ag) IDEs were screen printed on a flexible polyethylene terephthalate (PET) substrate followed by spin coating the active layer of P(VDF-TrFE)/graphene flower on its surface. It was observed that this sensor responds to a wide relative humidity range (RH%) of 8–98% with a fast response and recovery time of 0.8 s and 2.5 s for the capacitance, respectively. The fabricated sensor displayed an inversely proportional response between capacitance and RH%, while a directly proportional relationship was observed between its impedance and RH%. P(VDF-TrFE)/graphene flower-based flexible humidity sensor exhibited high sensitivity with an average change of capacitance as 0.0558 pF/RH%. Stability of obtained results was monitored for two weeks without any considerable change in the original values, signifying its high reliability. Various chemical, morphological, and electrical characterizations were performed to comprehensively study the humidity-sensing behavior of this advanced composite. The fabricated sensor was successfully used for the applications of health monitoring and measuring the water content in the environment.


Author(s):  
Jolly Bhadra ◽  
Hemalatha Parangusan ◽  
Zubair Ahmad ◽  
Shoaib Mallick ◽  
Farid Touati ◽  
...  

PANI coated Cu-ZnS porous microsphere structures have been synthesized by hydrothermal method and in-situ polymerization process. The synthesized composite is characterized by different techniques in order to study the structural, morphological and surface absorption properties. The experimental observation demonstrates that the PANI/1%Cu-ZnS composite has better sensitivity, fast response and good stability as compared to pure PANI and other PANI/CuZnS compositions. Finally, PANI/1% Cu-ZnS composite has been found to be optimized for the humidity sensors due to its well-distributed roughness, porosity and hydrophilicity. The average response and recovery times of the PANI/1% Cu-ZnS are found to be 42 s and 24 s, respectively, which outperform recent results.


2012 ◽  
Vol 101 (26) ◽  
pp. 261108 ◽  
Author(s):  
J. J. Hassan ◽  
M. A. Mahdi ◽  
S. J. Kasim ◽  
Naser M. Ahmed ◽  
H. Abu Hassan ◽  
...  

2020 ◽  
Vol 15 (7) ◽  
pp. 870-874
Author(s):  
Qi Qi ◽  
Qi Wang ◽  
Nanliu Liu ◽  
Xiaoping Zheng ◽  
Xiongjie Ding ◽  
...  

A flexible humidity sensor has been realized based on Co3O4 nanoneedles via a deposition technique. High humidity sensing and excellent flexible properties are observed in the tests. The impedance of the as-prepared sensor decreases by nearly three orders of magnitude with increasing relative humidity (RH) from 11% to 95% on a semilogarithmic scale. The response and recovery times are about 3 and 6 s respectively. The maximum hysteresis is less than 4% under 80% RH. No obvious changes for the sensing performance can be obtained after 100 bending/extending cycles and bending tests. These performances make the current sensor a good candidate for flexible humidity detection.


Proceedings ◽  
2018 ◽  
Vol 2 (13) ◽  
pp. 770
Author(s):  
Gita Nematbakhsh Abkenar ◽  
Jean-Paul Viricelle ◽  
Mathilde Rieu ◽  
Philippe Breuil

Mixed potential ammonia gas sensors were fabricated by using two sensing materials of Ni3V2O8 and Au-V2O5 as working electrodes, YSZ as electrolyte and platinum as reference electrode. The results have shown that the Ni3V2O8 sensors show cross-sensitivity toward NO gas. However, Au-V2O5 working electrodes displayed a high sensitivity to NH3 as well as fast response and recovery times at high temperatures. Furthermore, the results indicate that the selectivity of Au-V2O5 sensors increases by increasing temperature.


2021 ◽  
Author(s):  
Ruoling Chen ◽  
Long Li ◽  
Long Jiang ◽  
Xiangxiang Yu ◽  
Desheng Zhu ◽  
...  

Abstract P-type nanostructured photodetectors and phototransistors have been widely used in the field of photodetection due to their excellent electrical and optoelectronic characteristics. However, the large dark current of p-type photodetectors will limit the detectivity. Herein, we synthesized small-diameter single-crystalline p-type SnS nanowires (NWs) and then fabricated single SnS NW photodetectors and phototransistors. The device exhibits low noise and low dark current, and its noise current power is as low as 2.4 × 10−28 A2. Under 830 nm illumination and low power density of 0.12 mW cm2, the photoconductive gain, responsivity and detectivity of the photodetector are as high as 3.9 × 102, 2.6 × 102 A W−1 and 1.8 × 1013 Jones, respectively, at zero gate voltage. The rise and fall time of response are about 9.6 and 14 ms. The experimental results show that the small-diameter p-type SnS NWs have broad application prospects in high-performance and low-power photodetectors with high sensitivity, fast response speed and wide spectrum detection in the future.


Nanomaterials ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 2210
Author(s):  
Yao Yao ◽  
Xianhe Huang ◽  
Qiao Chen ◽  
Zhen Zhang ◽  
Weiwei Ling

In this paper, a high sensitivity and high stability quartz crystal microbalance (QCM) humidity sensor using polydopamine (PDA) coated cellulose nanocrystal (CNC)/graphene oxide (GO) (PDA@CNC/GO) nanocomposite as sensitive material is demonstrated. The PDA@CNC was prepared by the self-polymerization action on the surface of CNC, and it acted as filler material to form functional nanocomposite with GO. The material characteristics of PDA@CNC, CNC/GO and PDA@CNC/GO were analyzed by transmission electron microscope (TEM) and Fourier transform infrared spectroscopy (FTIR), respectively. The experimental results show that the introduction of PDA@CNC into GO film not only effectively enhanced the sensitivity of GO-based nanocomposite-coated QCM sensor but also significantly maintained high stability in the entire humidity range. The PDA@CNC/GO30-coated QCM humidity sensor exhibited a superior response sensitivity up to 54.66 Hz/% relative humidity (RH), while the change rate of dynamic resistance of the sensor in the humidity range of 11.3–97.3% RH is only 14% that is much smaller than that of CNC/GO-coated QCM. Besides, the effect of the PDA@CNC content on the sensitivity and stability of GO-based nanocomposite-coated QCM humidity was also studied. Moreover, other performances of PDA@CNC/GO-coated QCM humidity sensor, including humidity hysteresis, fast response and recovery and long-term stability, were systematically investigated. This work suggests that PDA@CNC/GO nanocomposite is a promising candidate material for realizing high sensitivity and high stability QCM humidity sensor in the entire humidity detection range.


Nanoscale ◽  
2014 ◽  
Vol 6 (12) ◽  
pp. 6521-6525 ◽  
Author(s):  
Ming Zhuo ◽  
Yuejiao Chen ◽  
Tao Fu ◽  
Haonan Zhang ◽  
Zhi Xu ◽  
...  

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.


Sign in / Sign up

Export Citation Format

Share Document