scholarly journals Visible Light Activated Room Temperature Gas Sensors Based on CaFe2O4 Nanopowders

Proceedings ◽  
2018 ◽  
Vol 2 (13) ◽  
pp. 834 ◽  
Author(s):  
Qomaruddin ◽  
Cristian Fàbrega ◽  
Andreas Waag ◽  
Andris Šutka ◽  
Olga Casals ◽  
...  
Keyword(s):  
Visible Light ◽  
Gas Sensors ◽  
Room Temperature ◽  
Oxide Semiconductor ◽  
Light Activation ◽  
Thermally Activated ◽  
Green Led ◽  
Sensor Activation ◽  
P Type ◽  
Visible Light Activation

Gas sensors based on CaFe2O4 nanopowders, which are p–type metal oxide semiconductor (MOX), have been fabricated and assessed for ethanol gas monitoring under visible light activation at room temperature. Regardless of their inferior sensitivity compared to thermally activated counterparts, the developed sensors have shown responsive sensing behavior towards ethanol vapors confirming the ability of using visible light for sensor activation. LEDs with different wavelengths (i.e., 465–590 nm) were employed. The highest sensitivity (3.7%) was reached using green LED activation that corresponds to the band gap of CaFe2O4.

scholarly journals A tunable volatile organic compound sensor by using PtOx/GQDs/TiO2 nanocomposite thin films at room temperature under visible-light activation

RSC Advances ◽  
2017 ◽  
Vol 7 (63) ◽  
pp. 39859-39868 ◽  
Author(s):  
Shaofeng Shao ◽  
Yunyun Chen ◽  
Shenbei Huang ◽  
Fan Jiang ◽  
Yunfei Wang ◽  
...  
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Visible Light ◽  
Gas Sensors ◽  
Room Temperature ◽  
Light Activation ◽  
Nanocomposite Thin Film ◽  
Nanocomposite Thin Films ◽  
Volatile Organic ◽  
Visible Light Activation

Pt/GQDs/TiO2 nanocomposite thin film-based gas sensors show tunable VOC sensing behaviour at room temperature under visible-light activation.

scholarly journals Visible light activation of room temperature NO 2 gas sensors based on ZnO, SnO 2 and In 2 O 3 sensitized with CdSe quantum dots

2016 ◽  
Vol 618 ◽  
pp. 253-262 ◽  
Author(s):  
A.S. Chizhov ◽  
M.N. Rumyantseva ◽  
R.B. Vasiliev ◽  
D.G. Filatova ◽  
K.A. Drozdov ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Visible Light ◽  
Gas Sensors ◽  
Room Temperature ◽  
Cdse Quantum Dots ◽  
Light Activation ◽  
Visible Light Activation

Practical room temperature formaldehyde sensing based on combination of visible-light activation and dipole modification

2021 ◽  
Author(s):  
Hongping Liang ◽  
Lanpeng Guo ◽  
Nengjie Cao ◽  
huiyun Hu ◽  
Hao Li ◽  
...  
Keyword(s):  
Visible Light ◽  
Indoor Air Quality ◽  
Indoor Air ◽  
Room Temperature ◽  
Quality Monitoring ◽  
Air Quality Monitoring ◽  
Light Activation ◽  
Formaldehyde Sensing ◽  
Modified Graphene ◽  
Visible Light Activation

Implementing sensitive and fast ppb-level formaldehyde sensing at room temperature is still extremely demanded for practical indoor air quality monitoring. Herein, we developed a visible-light sensitive and dipole modified graphene-based...

scholarly journals Light‐Activated Gas Sensors: Optically Activated 3D Thin‐Shell TiO 2 for Super‐Sensitive Chemoresistive Responses: Toward Visible Light Activation (Adv. Sci. 3/2021)

2021 ◽  
Vol 8 (3) ◽  
pp. 2170012
Author(s):  
Donghwi Cho ◽  
Jun Min Suh ◽  
Sang‐Hyeon Nam ◽  
Seo Yun Park ◽  
Minsu Park ◽  
...  
Keyword(s):  
Visible Light ◽  
Gas Sensors ◽  
Thin Shell ◽  
Light Activation ◽  
Visible Light Activation

scholarly journals Light Activation of Nanocrystalline Metal Oxides for Gas Sensing: Principles, Achievements, Challenges

Nanomaterials ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 892
Author(s):  
Artem Chizhov ◽  
Marina Rumyantseva ◽  
Alexander Gaskov
Keyword(s):  
Visible Light ◽  
Metal Oxides ◽  
Gas Sensors ◽  
Noble Metals ◽  
Gas Sensing ◽  
Uv Light ◽  
Light Activation ◽  
Gas Sensitivity ◽  
Semiconductor Gas Sensors ◽  
Visible Light Activation

The review deals with issues related to the principle of operation of resistive semiconductor gas sensors and the use of light activation instead of thermal heating when detecting gases. Information on the photoelectric and optical properties of nanocrystalline oxides SnO2, ZnO, In2O3, and WO3, which are the most widely used sensitive materials for semiconductor gas sensors, is presented. The activation of the gas sensitivity of semiconductor materials by both UV and visible light is considered. When activated by UV light, the typical approaches for creating materials are (i) the use of individual metal oxides, (ii) chemical modification with nanoparticles of noble metals and their oxides, (iii) and the creation of nanocomposite materials based on metal oxides. In the case of visible light activation, the approaches used to enhance the photo- and gas sensitivity of wide-gap metal oxides are (i) doping; (ii) spectral sensitization using dyes, narrow-gap semiconductor particles, and quantum dots; and (iii) addition of plasmon nanoparticles. Next, approaches to the description of the mechanism of the sensor response of semiconductor sensors under the action of light are considered.

scholarly journals Decoration of CuO NWs Gas Sensor with ZnO NPs for Improving NO2 Sensing Characteristics

Sensors ◽  
2021 ◽  
Vol 21 (6) ◽  
pp. 2103 ◽  
Author(s):  
Tae-Hee Han ◽  
So-Young Bak ◽  
Sangwoo Kim ◽  
Se Hyeong Lee ◽  
Ye-Ji Han ◽  
...  
Keyword(s):  
Gas Sensor ◽  
Gas Sensors ◽  
Sol Gel ◽  
Oxide Semiconductor ◽  
Zno Nps ◽  
X Ray ◽  
Semiconductor Gas Sensor ◽  
Initial Resistance ◽  
P Type ◽  
Sensing Characteristics

This paper introduces a method for improving the sensitivity to NO2 gas of a p-type metal oxide semiconductor gas sensor. The gas sensor was fabricated using CuO nanowires (NWs) grown through thermal oxidation and decorated with ZnO nanoparticles (NPs) using a sol-gel method. The CuO gas sensor with a ZnO heterojunction exhibited better sensitivity to NO2 gas than the pristine CuO gas sensor. The heterojunction in CuO/ZnO gas sensors caused a decrease in the width of the hole accumulation layer (HAL) and an increase in the initial resistance. The possibility to influence the width of the HAL helped improve the NO2 sensing characteristics of the gas sensor. The growth morphology, atomic composition, and crystal structure of the gas sensors were analyzed using field-emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray spectroscopy, and X-ray diffraction, respectively.

scholarly journals Visible Light Activation of Boronic Esters Enables Efficient Photoredox C(sp2 )-C(sp3 ) Cross-Couplings in Flow

2016 ◽  
Vol 128 (45) ◽  
pp. 14291-14295 ◽  
Author(s):  
Fabio Lima ◽  
Mikhail A. Kabeshov ◽  
Duc N. Tran ◽  
Claudio Battilocchio ◽  
Joerg Sedelmeier ◽  
...  
Keyword(s):  
Visible Light ◽  
Light Activation ◽  
Boronic Esters ◽  
Visible Light Activation

scholarly journals Silver Enhances Hematite Nanoparticles Based Ethanol Sensor Response and Selectivity at Room Temperature

Sensors ◽  
2021 ◽  
Vol 21 (2) ◽  
pp. 440
Author(s):  
Daniel Garcia-Osorio ◽  
Pilar Hidalgo-Falla ◽  
Henrique E. M. Peres ◽  
Josue M. Gonçalves ◽  
Koiti Araki ◽  
...  
Keyword(s):  
Volatile Organic Compounds ◽  
Organic Compounds ◽  
Gas Sensors ◽  
Room Temperature ◽  
Gas Sensing ◽  
Ethanol Vapor ◽  
Oxide Semiconductor ◽  
Charge Carrier Density ◽  
Ethanol Sensor ◽  
Volatile Organic

Gas sensors are fundamental for continuous online monitoring of volatile organic compounds. Gas sensors based on semiconductor materials have demonstrated to be highly competitive, but are generally made of expensive materials and operate at high temperatures, which are drawbacks of these technologies. Herein is described a novel ethanol sensor for room temperature (25 °C) measurements based on hematite (α‑Fe2O3)/silver nanoparticles. The AgNPs were shown to increase the oxide semiconductor charge carrier density, but especially to enhance the ethanol adsorption rate boosting the selectivity and sensitivity, thus allowing quantification of ethanol vapor in 2–35 mg L−1 range with an excellent linear relationship. In addition, the α-Fe2O3/Ag 3.0 wt% nanocomposite is cheap, and easy to make and process, imparting high perspectives for real applications in breath analyzers and/or sensors in food and beverage industries. This work contributes to the advance of gas sensing at ambient temperature as a competitive alternative for quantification of conventional volatile organic compounds.

Sign in / Sign up

Export Citation Format

Share Document