Room-Temperature H2 Gas Sensing Characterization of Graphene-Doped Porous Silicon via a Facile Solution Dropping Method

In this study, a graphene-doped porous silicon (G-doped/p-Si) substrate for low ppm H2 gas detection by an inexpensive synthesis route was proposed as a potential noble graphene-based gas sensor material and to understand the sensing mechanism. The G-doped/p-Si gas sensor was synthesized by a simple capillary force-assisted solution dropping method on p-Si substrates, whose porosity was generated through an electrochemical etching process. G-doped/p-Si was fabricated with various graphene concentrations and exploited as a H2 sensor operated at room temperature. The sensing mechanism of the sensor with/without graphene decoration on p-Si was proposed to elucidate the synergetic gas sensing effect generated from the interface between the graphene and p-type silicon.

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Optical Properties of Free-Standing Ultrahigh Porosity Silicon Films Prepared by Supercritical Drying

MRS Proceedings ◽

10.1557/proc-452-565 ◽

1996 ◽

Vol 452 ◽

Cited By ~ 11

Author(s):

J. Von Behren ◽

P. M. Fauchet ◽

E. H. Chimowitz ◽

C. T. Lira

Keyword(s):

Porous Silicon ◽

Electrochemical Etching ◽

Supercritical Drying ◽

Silicon Films ◽

Index Of Refraction ◽

Free Standing ◽

Crystal Silicon ◽

Si Substrates ◽

Type C ◽

P Type

AbstractHighly luminescent free-standing porous silicon thin films of excellent optical quality have been manufactured by using electrochemical etching and lift-off steps combined with supercritical drying. One to 50 μm thick free-standing layers made from highly (p+) and moderately (p) Boron doped single crystal silicon (c-Si) substrates have been produced with porosities (P) up to 95 %. The Fabry-Pérot fringes observed in the transmission and photoluminescence (PL) spectra are used to determine the refractive index. At the highest P the index of refraction is below 1.2 from the IR to 2 eV. The absorption coefficients follow a nearly exponential behavior in the energy range from 1.2 eV and 4 eV. The porosity corrected absorption spectra of free-standing films made from p type c-Si substrates are blue shifted with respect to those prepared from p+ substrates. For P > 70 % a blue shift is also observed in PL. At equal porosities the luminescence intensities of porous silicon films made from p+ and p type c-Si are different by one order of magnitude.

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Photo and electroluminescence of porous silicon layers

BIBECHANA ◽

10.3126/bibechana.v8i0.4897 ◽

2012 ◽

Vol 8 ◽

pp. 46-52

Author(s):

E Haji-Ali

Keyword(s):

Porous Silicon ◽

Light Emission ◽

Electrochemical Cell ◽

Electrochemical Etching ◽

Light Illumination ◽

Porous Layers ◽

Si Substrates ◽

Orange Yellow ◽

Intense Light ◽

P Type

Porous silicon layers were prepared by both chemical and electrochemical methods on n- and ptype Si substrates. In the former technique, light emission was obtained from p-type and n-type samples. It was found that intense light illumination during the preparation process was essential for PSi formation on n-type substrates.An efficient electrochemical cell with some useful features was designed for electrochemical etching of silicon. Various preparation parameters were studied and photoluminescence emissions ranging from dark red to light blue were obtained from PSi samples prepared on p-type substrates. N-type samples produced emissions ranging from dark red to orange-yellow. Electroluminescence of porous silicon samples showed that the color of the emission was the same as the photoluminescence color of the sample, and its intensity and duration depended on the current density passed through the sample. The effects of exposure of samples to air, storage in vacuum, and heat-treatment in air on luminescence intensity of the samples and preparation of patterned porous layers were also studied.Keywords: Porous silicon layers; photoluminescence; electroluminescenceDOI: http://dx.doi.org/10.3126/bibechana.v8i0.4897 BIBECHANA 8 (2012) 46-52

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Au@NiO core-shell nanoparticles as a p-type gas sensor: Novel synthesis, characterization, and their gas sensing properties with sensing mechanism

Sensors and Actuators B Chemical ◽

10.1016/j.snb.2018.04.119 ◽

2018 ◽

Vol 268 ◽

pp. 223-231 ◽

Cited By ~ 65

Author(s):

Sanjit Manohar Majhi ◽

Gautam Kumar Naik ◽

Hu-Jun Lee ◽

Ho-Geun Song ◽

Cheul-Ro Lee ◽

...

Keyword(s):

Gas Sensor ◽

Gas Sensing ◽

Core Shell ◽

Shell Nanoparticles ◽

Sensing Properties ◽

Sensing Mechanism ◽

Novel Synthesis ◽

Gas Sensing Properties ◽

P Type ◽

Core Shell Nanoparticles

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Gas-sensing and electrical properties of perovskite structure p-type barium-substituted bismuth ferrite

RSC Advances ◽

10.1039/c5ra01869b ◽

2015 ◽

Vol 5 (38) ◽

pp. 29618-29623 ◽

Cited By ~ 62

Author(s):

Guangzhi Dong ◽

Huiqing Fan ◽

Hailin Tian ◽

Jiawen Fang ◽

Qiang Li

Keyword(s):

Electrical Properties ◽

Equivalent Circuit ◽

Gas Sensor ◽

Perovskite Structure ◽

Gas Sensing ◽

Bismuth Ferrite ◽

Schematic Diagram ◽

Sensing Mechanism ◽

Reducing Gas ◽

P Type

Schematic diagram of the proposed gas-sensing mechanism for the p-type BiFeO3 based gas sensor: (a) and (c) in air, (b) and (d) in reducing gas, (e) simplified equivalent circuit.

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Gold and ZnO-Based Metal-Semiconductor Network for Highly Sensitive Room-Temperature Gas Sensing

Sensors ◽

10.3390/s19183815 ◽

2019 ◽

Vol 19 (18) ◽

pp. 3815

Author(s):

Renyun Zhang ◽

Magnus Hummelgård ◽

Joel Ljunggren ◽

Håkan Olin

Keyword(s):

Solar Cells ◽

Gas Sensor ◽

Network Structure ◽

Room Temperature ◽

Gas Sensing ◽

Zno Nanowires ◽

Gold Particles ◽

Highly Sensitive ◽

Semiconductor Electronics ◽

New Type

Metal-semiconductor junctions and interfaces have been studied for many years due to their importance in applications such as semiconductor electronics and solar cells. However, semiconductor-metal networks are less studied because there is a lack of effective methods to fabricate such structures. Here, we report a novel Au–ZnO-based metal-semiconductor (M-S)n network in which ZnO nanowires were grown horizontally on gold particles and extended to reach the neighboring particles, forming an (M-S)n network. The (M-S)n network was further used as a gas sensor for sensing ethanol and acetone gases. The results show that the (M-S)n network is sensitive to ethanol (28.1 ppm) and acetone (22.3 ppm) gases and has the capacity to recognize the two gases based on differences in the saturation time. This study provides a method for producing a new type of metal-semiconductor network structure and demonstrates its application in gas sensing.

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Sensing mechanism of an optimized room temperature optical hydrogen gas sensor made of zinc oxide thin films

Journal of Materials Research and Technology ◽

10.1016/j.jmrt.2020.07.086 ◽

2020 ◽

Vol 9 (5) ◽

pp. 10624-10634

Author(s):

Siti Nor Aliffah Mustaffa ◽

Nurul Assikin Ariffin ◽

Ahmed Lateef Khalaf ◽

Mohd. Hanif Yaacob ◽

Nizam Tamchek ◽

...

Keyword(s):

Thin Films ◽

Zinc Oxide ◽

Gas Sensor ◽

Room Temperature ◽

Hydrogen Gas ◽

Oxide Thin Films ◽

Sensing Mechanism

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Enhancing room-temperature NO2 gas sensing performance based on a metal phthalocyanine/graphene quantum dot hybrid material

RSC Advances ◽

10.1039/d0ra10310a ◽

2021 ◽

Vol 11 (10) ◽

pp. 5618-5628

Author(s):

Wenkai Jiang ◽

Xinwei Chen ◽

Tao Wang ◽

Bolong Li ◽

Min Zeng ◽

...

Keyword(s):

Quantum Dot ◽

Gas Sensor ◽

Hybrid Material ◽

High Performance ◽

Room Temperature ◽

Gas Sensing ◽

Metal Phthalocyanine ◽

Graphene Quantum Dot ◽

Sensing Performance

A high performance gas sensor based on a metal phthalocyanine/graphene quantum dot hybrid material was fabricated for NO2 detection at room-temperature.

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