Electrochemical Sensor for Detection of Para-Nitrophenol Based on Modified Porous Silicon

2014 ◽  
Vol 605 ◽  
pp. 115-118 ◽  
Author(s):  
S. Belhousse ◽  
K. Lasmi ◽  
I. Mezaache ◽  
T. Sedrati ◽  
N. Belhaneche ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Cyclic Voltammetry ◽  
Porous Silicon ◽  
Silicon Surface ◽  
Electrochemical Etching ◽  
High Sensitivity ◽  
Hybrid Structures ◽  
Porous Silicon Surface ◽  
Very High ◽  
Scanning Electron

The behavior of a modified porous silicon surface (PSi) with polythiophene (PTh) for para-nitrophenol (p-NPh) detection by cyclic voltammetry was studied. Nitrophenols are organic compounds which are the most used in the production of pesticides but also in the dyes and pharmaceuticals. In particular, p-NPh is a toxic derivative of the parathion insecticide and is considered as major toxic polluant because it is soluble and stable in water so it can affect soil. Porous silicon was prepared by electrochemical etching and it was modified by an oxide layer. PTh films were grown on this surface using electropolymerization in acetonitrile in the presence of thiophene monomer.The morphology of the fabricated PSi/PTh hybrid structures were characterized by scanning electron microscopy (SEM). Cyclic voltammetry and amperometry were used to study the proposed electrochemical p-NPh sensor. The performance of the proposed sensor was tested under differents conditions and we note a very high sensitivity; in particular, the linearity of the sensor for the detection of para-nitrophenol was observed from 3×108to 1.5 ×104M with a detection limit of 6×109M.

High Sensitivity Electrochemical Multisensors based on Graphene-PANI Nanocomposite for Simultaneous Detection of Glucose and Urea

2016 ◽  
Vol 19 (3) ◽  
pp. 145-150 ◽  
Author(s):  
Meysam Karimi ◽  
Mohammad Rabiee ◽  
Mojgan Abdolrahim ◽  
Mohammadreza Tahriri ◽  
Daryoosh Vashayee ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Cyclic Voltammetry ◽  
Simultaneous Detection ◽  
High Sensitivity ◽  
Xrd Analysis ◽  
Experimental Results ◽  
X Ray Diffraction ◽  
X Ray ◽  
Scanning Electron

We present a study of the effect of graphene–PANI nanocomposites on the sensitivity of the urea and glucose multisensory. We used an electroctrochemical multisensor based on two electrodes located in a reservoir with two separate channels. The urease and glu-cose oxidase (GOD) were employed for detecting the urea and glucose, respectively. We characterized the graphene and graphene-PANI samples with X-ray Diffraction (XRD) analysis and scanning electron microscopy (SEM) observations. We further performed the Cyclic voltammetry and Amperometry tests. The collected experimental results revealed that the intensity of the peak significantly increases with the concentration of the urea and glucose.

scholarly journals Laccase-Based Biosensor Encapsulated in a Galactomannan-Chitosan Composite for the Evaluation of Phenolic Compounds

Biosensors ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 70
Author(s):  
Imane Boubezari ◽  
François Bessueille ◽  
Anne Bonhomme ◽  
Gaëtan Raimondi ◽  
Ali Zazoua ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Cyclic Voltammetry ◽  
Laccase Activity ◽  
Valuable Alternative ◽  
M 10 ◽  
First Time ◽  
Chitosan Composite ◽  
Very High ◽  
Scanning Electron

Galactomannan, a neutral polysaccharide, was extracted from carob seeds and characterized. It was used for the first time for the fabrication of a laccase-based biosensor by the encapsulation of laccase in a chitosan+galactomannan composite. The fabricated biosensor was characterized by FTIR, scanning electron microscopy and cyclic voltammetry. The pyrocatechol detection was obtained by cyclic voltammetry measurements, through the detection of o-quinone at −0.447 V. The laccase activity was well preserved in the chitosan+galactomannan composite and the sensitivity of detection of pyrocatechol in the 10−16 M–10−4 M range was very high. The voltammetric response of the biosensor was stable for more than two weeks. To estimate the antioxidant capacity of olive oil samples, it was shown that the obtained laccase-based biosensor is a valuable alternative to the colorimetric Folin–Ciocalteu method.

scholarly journals Preparation and Characterisation of Metallorganic Precursors Derived Iron Oxides on Porous Silicon Layers

2020 ◽  
Vol 995 ◽  
pp. 63-68
Author(s):  
Sivakumar Balakrishnan ◽  
Yurii K. Gun’ko ◽  
Gerhard F. Swiegers ◽  
Tatiana S. Perova
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Magnetic Nanoparticles ◽  
Porous Silicon ◽  
Iron Oxides ◽  
Silicon Surface ◽  
Scientific Community ◽  
Magnetic Measurements ◽  
Chemical Functionalization ◽  
Scanning Electron

Porous silicon has generated interest in scientific community after its photoluminescence discovery and thereafter, research was focused on to the chemical functionalization of silicon and subsequent anchoring of nanoparticles onto silicon surface. In the present work, the porous silicon has been effectively modified with magnetic nanoparticles which were prepared through metallorganic approach. The as-fabricated magnetic-porous silicon composites were characterised using FTIR and Raman spectroscopies, Scanning Electron Microscopy (SEM) as well as magnetic measurements.

Microscopic Wetting at Microstructured Surface of Porous Silicon

2009 ◽  
Author(s):  
Gyoko Nagayama ◽  
Ryuji Ando ◽  
Takaharu Tsuruta
Keyword(s):  
Contact Angle ◽  
Chemical Composition ◽  
Porous Silicon ◽  
Silicon Substrate ◽  
Water Droplet ◽  
Silicon Surface ◽  
Electrochemical Etching ◽  
Pure Water ◽  
Practical Applications ◽  
Porous Silicon Surface

Surface wettability is an important factor for micro/nanoscale thermal fluidic systems and it has attracted much interest for both fundamental research and practical applications. As one of the most attractive materials with controllable wettability, porous silicon is easy to be produced by the electrochemical etching. In this study, the effects of the microstructures of porous silicon on the wetting behavior of a pure water droplet were investigated experimentally. The solid-liquid contacting surface of the porous silicon substrate was prepared by varying both the geometrical microstructure and the chemical composition. The anodic etching was applied to the n type silicon substrate of orientation (100) and the geometrical microstructures of porous silicon were controlled by varying the fabrication conditions of the electrochemical etching. The pores of diameter ranging from 1–6 micrometers and the porosity up to 0.8 were obtained. Also, the surface chemical composition was controlled by coating the SiO2 layer or the CYTOP fluoropolymer layer directly on the porous silicon surface. The contact angle of the pure water droplet was measured at the prepared porous silicon surface in a room with constant temperature and humidity. The effects of the microstructures on the contact angle were discussed and the results were compared to both the classical theoretical models and a modified model based on the molecular dynamics simulations.

Angular Ellipsometry of Porous Silicon Surface Layers

2020 ◽  
Vol 12 (3) ◽  
pp. 03024-1-03024-4
Author(s):  
L. V. Poperenko ◽  
◽  
S. G. Rozouvan ◽  
I. V. Yurgelevych ◽  
P. O. Lishchuk ◽  
...  
Keyword(s):  
Porous Silicon ◽  
Silicon Surface ◽  
Surface Layers ◽  
Porous Silicon Surface

Zinc Electrodeposition in the Presence of an Aqueous Electrolyte Containing 1-Ethylpyridinium Bromide: Unexpected Oddities

2017 ◽  
Vol 70 (9) ◽  
pp. 1025 ◽  
Author(s):  
Max E. Easton ◽  
Lisa C. Player ◽  
Anthony F. Masters ◽  
Thomas Maschmeyer
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Cyclic Voltammetry ◽  
Aqueous Electrolyte ◽  
Redox Couple ◽  
Nucleation Process ◽  
Zinc Electrodeposition ◽  
Unusual Behaviour ◽  
Scanning Electron

The reversible electrodeposition of zinc was investigated in an aqueous electrolyte containing zinc bromide (50 mM) and 1-ethylpyridinium bromide ([C2Py]Br, 50 mM) by cyclic voltammetry, chronoamperometry, and scanning electron microscopy. Unusual voltammetric behaviour for the Zn/ZnII redox couple was observed in the presence of [C2Py]Br. Passivation of the redox couple was observed after a single deposition–stripping cycle at switching potentials more negative than −1.25 V versus Ag/AgCl. This unusual behaviour was attributed to the reduction of 1-ethylpyridinium cations to pyridyl radicals and their follow-up reactions, which influenced the zinc electrochemistry. This behaviour was further seen to modify the nucleation process of electrodeposition, which altered the morphology of zinc electrodeposits.

Magnetic Properties of Ferrous Ferric Oxide Confined in Porous Silicon

2010 ◽  
Vol 663-665 ◽  
pp. 1142-1145
Author(s):  
Yuan Ming Huang ◽  
Bao Gai Zhai ◽  
Qing Lan Ma ◽  
Ming Meng
Keyword(s):  
Electron Microscopy ◽  
Magnetic Properties ◽  
Iron Oxide ◽  
Porous Silicon ◽  
Ferrous Iron ◽  
Silicon Film ◽  
X Ray ◽  
Loop Measurement ◽  
Scanning Electron

During the chemical synthesis nanometer-sized particles of ferrous iron oxide were in situ infiltrated into the mesopores in a porous silicon film. The microstructures of porous silicon and the magnetic properties of the nanometer-sized particles of the ferrous iron oxide were characterized with scanning electron microscopy, X-ray diffractometry, and the hysteresis loop measurement, respectively. Our results have demonstrated that the magnetic properties of the nanometer-sized Fe3O4 particles can be dramatically modified when they are confined into the mesopores of the porous silicon film.

Chemical Modification of the Porous Silicon Surface

1994 ◽  
Vol 358 ◽  
Author(s):  
Eric J. Lee ◽  
James S. Ha ◽  
Michael J. Sailor
Keyword(s):  
Porous Silicon ◽  
Chemical Modification ◽  
Formic Acid ◽  
Gas Phase ◽  
Silicon Surface ◽  
Chemical Vapor ◽  
Luminescence Quenching ◽  
Porous Silicon Surface ◽  
Phase Water ◽  
Surface Modified

ABSTRACTThe porous silicon (PS) surface is derivatized with ethanol, triethylsilanol and formic acid as well as oxidized with water. The two reactions used to prepare these surfaces are discussed, and FTIR spectra of the products are presented. Surface-modified PS retains 10-40% of its original photoluminescence. PS-derivatives display reversible luminescence quenching by gas phase water, ethanol, acetonitrile and benzene. The extent of quenching varies with different PS-derivatives depending on the interaction of the chemical vapor with the modified PS surfaces.

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