Light‐Induced Solid‐State Protrusion of Gold Nanowires and Their Derivatives for Sensing Applications

Purpose Design, fabricate and evaluate all-solid-state wearable sensor systems that can monitor ion concentrations in human sweat to provide real time health analysis and disease diagnosis capabilities. Design/methodology/approach A human health monitoring system includes disposable customized flexible electrode array and a compact signal transmission-processing electronic unit. Findings Patterned rGO (reduced-graphene oxide) layers can replace traditional metal electrodes for the fabrication of free-standing all solid film sensors to provide improved flexibility, sensitivity, selectivity, and stability in ion concentration monitoring. Electrochemical measurements show the open circuit potential of current selective electrodes exhibit near Nernst responses versus Na+ and K+ ion concentration in sweat. These signals show great stability during a typical measurement period of 3 weeks. Sensor performances evaluated through real time measurements on human subjects show strong correlations between subject activity and sweating levels, confirming high degree of robustness, sensitivity, reliability and practicality of current sensor systems. Originality/value In improving flexibility, stability and interfacial coherency of chemical sensor arrays, rGO films have been the developed as a high-performance alternative to conventional electrode with significant cost and processing complexity reduction. rGO supported solid state electrode arrays have been found to have linear potential response versus ion concentration, suitable for electrochemical sensing applications. Current sweat sensor system has a high degree of integration, including electrode arrays, signal processing circuits, and data visualization interfaces.

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Nonlinear Optical Pigments. Two-Photon Absorption in Crosslinked Conjugated Polymers and Prospects for Remote Nonlinear Optical Thermometry

Polymers ◽

10.3390/polym12081670 ◽

2020 ◽

Vol 12 (8) ◽

pp. 1670

Author(s):

Jan K. Zaręba ◽

Marcin Nyk ◽

Marek Samoć

Keyword(s):

Solid State ◽

Conjugated Polymers ◽

Nonlinear Optical ◽

Photon Absorption ◽

Model Compounds ◽

Two Photon Absorption ◽

Two Photon ◽

Sensing Applications ◽

Spectrally Resolved ◽

The Impact

Nonlinear optical (NLO) pigments are compounds insoluble in solvents that exhibit phenomena related to nonlinear optical susceptibilities (χ(n) where n = 2,3,...), e.g., two-photon absorption (2PA) which is related to the imaginary part of χ(3). Determination of spectrally-resolved 2PA properties for NLO pigments of macromolecular nature, such as coordination polymers or crosslinked polymers, has long been a challenging issue due to their particulate form, precluding characterizations with standard techniques such as Z-scan. In this contribution, we investigate thus far unknown spectrally-resolved 2PA properties of a new subclass of NLO pigments—crosslinked conjugated polymers. The studied compounds are built up from electron-donating (triphenylamine) and electron-withdrawing (2,2’-bipyridine) structural fragments joined by vinylene (Pol1) or vinyl(4-ethynylphenyl) (Pol2) aromatic bridges. 2PA properties of these polymers have been characterized in broad spectral range by specially modified two-photon excited fluorescence (TPEF) techniques: solid state TPEF (SSTPEF) and internal standard TPEF (ISTPEF). The impact of self-aggregation of aromatic backbones on the 2PA properties of the polymers has been evaluated through extended comparisons of NLO parameters, i.e., 2PA cross sections (σ2) and molar-mass normalized 2PA merit factors (σ2/M) with those of small-molecular model compounds: Mod1 and Mod2. By doing this, we found that the 2PA response of Pol1 and Pol2 is improved 2–3 times versus respective model compounds in the solid state form. Further comparisons with 2PA results collected for diluted solutions of Mod1 and Mod2 supports the notion that self-aggregated structure contributes to the observed enhancement of 2PA response. On the other hand, it is clear that Pol1 and Pol2 suffer from aggregation-caused quenching phenomenon, well reflected in time-resolved fluorescence properties as well as in relatively low values of quantum yield of fluorescence. Accordingly, despite improved intrinsic 2PA response, the effective intensity of two-photon excited emission for Pol1 and Pol2 is slightly lower relative to Mod1 and Mod2. Finally, we explore temperature-resolved luminescence properties under one- (377 nm), two- (820 nm), and three-photon excitation (1020 nm) conditions of postsynthetically Eu3+-functionalized material, Pol1-Eu, and discuss its suitability for temperature sensing applications.

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Optothermotronic effect as an ultrasensitive thermal sensing technology for solid-state electronics

Science Advances ◽

10.1126/sciadv.aay2671 ◽

2020 ◽

Vol 6 (22) ◽

pp. eaay2671 ◽

Cited By ~ 2

Author(s):

T. Dinh ◽

T. Nguyen ◽

A. R. M. Foisal ◽

H.-P. Phan ◽

T.-K. Nguyen ◽

...

Keyword(s):

Solid State ◽

High Performance ◽

Charge Carriers ◽

Thermal Excitation ◽

Light Illumination ◽

Solid State Electronics ◽

Sensing Applications ◽

Sensing Technology ◽

Thermal Sensing ◽

Sensing Performance

The thermal excitation, regulation, and detection of charge carriers in solid-state electronics have attracted great attention toward high-performance sensing applications but still face major challenges. Manipulating thermal excitation and transport of charge carriers in nanoheterostructures, we report a giant temperature sensing effect in semiconductor nanofilms via optoelectronic coupling, termed optothermotronics. A gradient of charge carriers in the nanofilms under nonuniform light illumination is coupled with an electric tuning current to enhance the performance of the thermal sensing effect. As a proof of concept, we used silicon carbide (SiC) nanofilms that form nanoheterostructures on silicon (Si). The sensing performance based on the thermal excitation of charge carriers in SiC is enhanced by at least 100 times through photon excitation, with a giant temperature coefficient of resistance (TCR) of up to −50%/K. Our findings could be used to substantially enhance the thermal sensing performance of solid-state electronics beyond the present sensing technologies.

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Biomimetic Solid-State Nanochannels for Chemical and Biological Sensing Applications

TrAC Trends in Analytical Chemistry ◽

10.1016/j.trac.2021.116425 ◽

2021 ◽

pp. 116425

Author(s):

Gregorio Laucirica ◽

Yamili Toum Terrones ◽

Vanina Cayón ◽

María Lorena Cortez ◽

Maria Eugenia Toimil-Molares ◽

...

Keyword(s):

Solid State ◽

Biological Sensing ◽

Sensing Applications

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Solid state laser technology and atmospheric sensing applications

10.1063/1.54900 ◽

1998 ◽

Cited By ~ 2

Author(s):

James C. Barnes

Keyword(s):

Solid State ◽

Solid State Laser ◽

Laser Technology ◽

State Laser ◽

Sensing Applications ◽

Atmospheric Sensing

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Solid-State Dispersions of Platinum in the SnO2 and Fe2O3 Nanomaterials

Nanomaterials ◽

10.3390/nano11123349 ◽

2021 ◽

Vol 11 (12) ◽

pp. 3349

Author(s):

Edi Radin ◽

Goran Štefanić ◽

Goran Dražić ◽

Ivan Marić ◽

Tanja Jurkin ◽

...

Keyword(s):

Electron Microscopy ◽

Solid Solution ◽

Solid State ◽

Crystal Lattice ◽

Platinum Nanoparticles ◽

Gas Sensing ◽

Pt Nanoparticles ◽

Experimental Conditions ◽

Oxide Supports ◽

Sensing Applications

The dispersion of platinum (Pt) on metal oxide supports is important for catalytic and gas sensing applications. In this work, we used mechanochemical dispersion and compatible Fe(II) acetate, Sn(II) acetate and Pt(II) acetylacetonate powders to better disperse Pt in Fe2O3 and SnO2. The dispersion of platinum in SnO2 is significantly different from the dispersion of Pt over Fe2O3. Electron microscopy has shown that the elements Sn, O and Pt are homogeneously dispersed in α-SnO2 (cassiterite), indicating the formation of a (Pt,Sn)O2 solid solution. In contrast, platinum is dispersed in α-Fe2O3 (hematite) mainly in the form of isolated Pt nanoparticles despite the oxidative conditions during annealing. The size of the dispersed Pt nanoparticles over α-Fe2O3 can be controlled by changing the experimental conditions and is set to 2.2, 1.2 and 0.8 nm. The rather different Pt dispersion in α-SnO2 and α-Fe2O3 is due to the fact that Pt4+ can be stabilized in the α-SnO2 structure by replacing Sn4+ with Pt4+ in the crystal lattice, while the substitution of Fe3+ with Pt4+ is unfavorable and Pt4+ is mainly expelled from the lattice at the surface of α-Fe2O3 to form isolated platinum nanoparticles.

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Layer-by-Layer Assembly of Electroactive Dye/LDHs Nanoplatelet Matrix Film for Advanced Dual Electro-optical Sensing Applications

Nanoscale Research Letters ◽

10.1186/s11671-020-03442-6 ◽

2020 ◽

Vol 15 (1) ◽

Author(s):

Sepehr Lajevardi Esfahani ◽

Shohre Rouhani ◽

Zahra Ranjbar

Keyword(s):

Solid State ◽

Molecular Design ◽

High Sensitivity ◽

Optical Methods ◽

Detection Methods ◽

Layer By Layer ◽

Alizarin Red ◽

Sensing Applications ◽

Lbl Assembly ◽

Assembly Technique

Abstract It proved that the most destructive effects of the toxic Al3+ ion on the human nervous system and disease that are involved with this system, such as Alzheimer's. The development of solid-state electrodes is still in its infancy during the sensor-based detection methods for Al3+. Hence, in this study, a novel flexible ITO/PET-based electrochemical solid-state sensor was designed and constructed. Modification of the surface of electrode bedding was done by layer-by-layer (LbL) assembly of Mg–Al LDH. nanoplatelets along with alizarin red S (ARS) in an interconnected matrix film. In the molecular design of sensing base of the electrode, the electroactive organic units (ARS molecules) present in the ITO/PET-layered (ARS/LDHs)n matrix are involved in electrochemical reactions when exposed to the target molecule (Al3+ ion), so the electrochemical changes of the new formed Al-chelated system are detectable. This type of sensor is used for sensitive and selective detection of Al3+. The minimum sheet resistance, morphology and high electrocatalytic activity of the modified matrix film are obtained in the fifth cycle of LbL assembly technique. In this electrochemical sensor, both electrochemical and optical methods were detected with high sensitivity and selectivity of Al3+, so that in a cyclic voltammetry electrochemical method, the lower detection limit of 10.1 nM with a linear range of [0.2–120 μM] was obtained compared to the fluorescence-based optical method.

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Rational Synthesis and Optimization of Multifunctional Solid-State Gas Sensors

MRS Proceedings ◽

10.1557/proc-828-a4.1 ◽

2004 ◽

Vol 828 ◽

Author(s):

Johannes Schwank ◽

Ghenadii Korotcenkov

Keyword(s):

Solid State ◽

Gas Sensors ◽

Active Sites ◽

Gas Sensing ◽

Heterogeneous Systems ◽

Sensor Applications ◽

Sensing Applications ◽

Long Time ◽

Overall Performance ◽

Scale Design

ABSTRACTA new approach is discussed for the rational synthesis and development of optimized multifunctional solid-state gas sensors. Multifunctionality—the incorporation of multiple types of reactivities into a material, such as acid and/or base functionalities, oxidation and/or reduction functionalities, etc.—isa requirement in many gas sensing applications. The front end of many gas sensors contains catalytic layers, so that optimization of catalysts and optimization of gas sensors can be carried out in a synergistic fashion.Multifunctionality presents unique challenges to rational catalyst and sensor systems development because the overall performance of the material is a convolution of the performance of the various subcomponents, and optimization of these individual subcomponents in isolation does not necessarily lead to optimal, or even acceptable, overall performance. A major obstacle to dealing with these difficulties is the inherent complexity of heterogeneous systems prepared by traditional approaches, which makes it difficult to unambiguously identify the compositions and morphologies of the local active sites and their interactions. Further complicating the problem is the requirement to function in environments that can vary on both short and long time scales. A key to understanding, controlling, and optimizing these materials is the ability to produce and study well-defined sensor materials with well-defined composition and morphology, with the flexibility to vary the composition easily without jeopardizing the structural uniformity.The development of new or improved materials for gas sensor applications requires a search for novel and innovative approaches to the nano-scale design of these materials. The use of the technology of surface modification by successive ionic layer deposition (SILD) method is such an innovative approach that will be discussed in this paper.

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Thin Film of Giant Magnetoresistance (GMR) Material Prepared by Sputtering Method

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.770.1 ◽

2013 ◽

Vol 770 ◽

pp. 1-9 ◽

Cited By ~ 2

Author(s):

Mitra Djamal ◽

Ramli

Keyword(s):

Magnetic Field ◽

Thin Film ◽

Solid State ◽

Giant Magnetoresistance ◽

Magnetic Sensor ◽

Sensor Data ◽

Sensing Applications ◽

Field Sensing ◽

Low Magnetic Field ◽

Magnetic Field Sensing

In recent decades, a new magnetic sensor based on magnetoresistance effect is highly researched and developed intensively. GMR material has great potential as next generation magnetic field sensing devices. It has also good magnetic and electric properties, and high potential to be developed into various applications of electronic devices such as: magnetic field sensor, current measurements, linear and rotational position sensor, data storage, head recording, and non-volatile magnetic random access memory. GMR material can be developed to be solid state magnetic sensors that are widely used in low field magnetic sensing applications. A solid state magnetic sensor can directly convert magnetic field into resistance, which can be easily detected by applying a sense current or voltage. Generally, there are many sensors for measuring the low magnetic field, such as: fluxgate sensor, Hall sensor, induction coil, GMR sensor, and SQUID sensor. Compared to other low magnetic field sensing techniques, solid state sensors have demonstrated many advantages, such as: small size (<0.1mm2), low power, high sensitivity (~0.1Oe) and good compatibility with CMOS technology. The thin film of GMR is usually prepared using: sputtering, electro deposition or molecular beam epitaxy (MBE) techniques. But so far, not many researchers reported the manufacture of thin film of GMR by dc-Opposed Target Magnetron Sputtering (dc-OTMS). In this paper, we inform the development of GMR thin film with sandwich and spin valve structures using dc-OTMS method. We have also developed organic GMR with Alq3 as a spacer layer.

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