Read by QxMD icon Read

Silicon nanoparticles

Zhi-Qiang Fan, Wei-Jia Zhang, Qiang Ma, Lanqin Yan, Lihua Xu, Yao-Long Fu
In this paper, we investigated the optical and electrical characteristics of the hybrid solar cells using silicon pyramid/Ag nanoparticles and nanowire/Ag nanoparticles nanocomposite structures, which are obtained by the Ag-assisted electro-less etching method. And we introduced the application of the physical and chemical properties for Ag nanoparticles on four kinds of solar cells: silicon pyramid, silicon pyramid /PEDOT:PSS silicon nanowrie, silicon nanowire/PEDOT:PSS. We simulated these structures with the absorption for different parameters...
September 22, 2017: ACS Applied Materials & Interfaces
L Mehrvar, M Sadeghipari, S H Tavassoli, S Mohajerzadeh, M Fathipour
Surface enhanced Raman scattering (SERS) systems with large number of active sites exhibit superior capability in detection of low concentration analytes. In this paper, we present theoretical as well as experimental studies on the optical properties of a unique hybrid nanostructure, Ag NPs decorated silicon double nanocones (Si-DNCs) array, which provide high density of hot spots. The Si-DNC array is fabricated by employing electron beam lithography together with plasma etching process. Multipole analysis of the scattering spectra, based on the multipole expansion theory, confirms that the toroidal dipole moment dominates over other electric and magnetic multipole moments in the Si-DNCs array...
September 21, 2017: Scientific Reports
Konstantin Tamarov, Andrey Sviridov, Wujun Xu, Markus Malo, Valery Andreev, Victor Yu Timoshenko, Vesa-Pekka Lehto
The current contrast agents utilized in ultrasound (US) imaging are based on microbubbles which, however, suffer from a short lifetime in the systemic circulation. The present study introduces a new type of contrast agents for US imaging based on bioresorbable Janus nanoparticles (NPs) that are able to generate microbubbles in situ under US radiation for extended time. The Janus NPs were fabricated from porous silicon (PSi) that was modified via a nanostopper technique. The technique was exploited to prepare PSi NPs which had hydrophobic pore walls (inner face) while the external surfaces of the NPs (outer face) were hydrophilic...
September 18, 2017: ACS Applied Materials & Interfaces
Hashim Alhmoud, Anna Cifuentes-Rius, Bahman Delalat, David G Lancaster, Nicolas H Voelcker
In order to address the issue of pathogenic bacterial colonization of diabetic wounds, a more direct and robust approach is required, which relies on a physical form of bacterial destruction in addition to the conventional biochemical approach (i.e. antibiotics). Targeted bacterial destruction through the use of photothermally active nanomaterials has recently come into the spotlight as a viable approach to solving the rising problem of antibiotic resistant microorganisms. Materials with high absorption coefficients in the near infrared (NIR) region of the electromagnetic spectrum show promise as alternative antibacterial therapeutic agents, since they preclude the development of bacterial resistance and can be activated on demand...
September 14, 2017: ACS Applied Materials & Interfaces
Ville Rontu, Anne Selent, Vladimir Zhivonitko, Gianmario Scotti, Igor Koptyug, Ville-Veikko Telkki, Sami Franssila
Microreactors attract a significant interest for chemical synthesis due to benefits of small scales such as high surface to volume ratio, rapid thermal ramping and well-understood laminar flows. The suitability of atomic layer deposition for applying of both the catalyst nanoparticles and the support material on the surfaces of channels of microfabricated silicon microreactors is demonstrated in this research. Continuous flow hydrogenation of propene into propane at low temperatures with TiO₂ supported catalytic Pt nanoparticles was used as a model reaction...
September 13, 2017: Chemistry: a European Journal
Abhijit Roy, Arpan Maiti, Tapas Kumar Chini, Biswarup Satpati
This paper reports on a simple and cost-effective process of developing a stable surface-enhanced Raman scattering (SERS) substrate based on silver (Ag) nanoparticles deposited on silicon (Si) surface. Durability is an important issue for preparing SERS active substrate as silver nanostructures are prone to rapid surface oxidation when exposed to ambient conditions, which may result in the loss of the enhancement capabilities in a short period of time. Here, we employ the galvanic displacement method to produce Ag nanoparticles on Si(100) substrate prepatterned with arrays of micropyramids by chemical etching, and subsequently, separate pieces of such substrates were annealed in oxygen and nitrogen environments at 550 °C...
September 20, 2017: ACS Applied Materials & Interfaces
Aleksander Matavž, Vid Bobnar, Barbara Malic
The surface properties of a substrate are among the most important parameters in the printing technology of functional materials, determining not only the printing resolution but also the stability of the printed features. This paper addresses the wetting difficulties encountered during inkjet printing on homogeneous substrates as a result of improper surface properties. We show that the wetting of a substrate and, consequently, the quality of the printed pattern, can be mediated through the deposition of polymeric layers that are a few nanometers thick...
September 12, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
Biyu Jin, Mingzhu Liu, Qinghua Zhang, Xiaoli Zhan, Fengqiu Chen
In this work, a novel substrate building block, magnetic Fe3O4 nanoparticles armed with dopamine molecules were developed via mussel-inspired metal-coordination bonds. Combined with glycidyl methacrylate, polydimethylsiloxane propyl ether methacrylate, and diethylenetriamine, the original silicone oil swelling slippery liquid-infused porous surfaces (SLIPS) were first prepared by reversible coordinate bonds and strong covalent bonds cross-linking process. The matrix mechanical characteristics and surface physicochemical properties were systematically investigated...
September 22, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
Hamid Sadabadi, Muthukumaran Packirisamy
The development of sensitive platforms for the detection of biomolecules recognition is an extremely important problem in clinical diagnostics. In microcantilever (MC) transducers, surface-stress is induced upon bimolecular interaction which is translated into MC deflection. This paper presents a cost-effective and ultra-sensitive MC-based biosensing platform. To address these goals, the need for costly high-resolution read-out system has been eliminated by reducing the cantilever compliance through developing a polymer-based cantilever...
September 8, 2017: Scientific Reports
Chiara Novara, Alessandro Chiadò, Niccolò Paccotti, Silvia Catuogno, Carla Lucia Esposito, Gerolama Condorelli, Vittorio De Franciscis, Francesco Geobaldo, Paola Rivolo, Fabrizio Giorgis
In this work, SERS-based microfluidic PDMS chips integrating silver-coated porous silicon membranes were used for the detection and quantitation of microRNAs (miRNAs), which consist of short regulatory non-coding RNA sequences typically over- or under-expressed in connection with several diseases such as oncogenesis. In detail, metal-dielectric nanostructures which provide noticeable Raman enhancements were functionalized according to a biological protocol, adapted and optimized from an enzyme-linked immunosorbent assay (ELISA), for the detection of miR-222...
September 8, 2017: Faraday Discussions
Huayi Shi, Na Chen, Yuanyuan Su, Houyu Wang, Yao He
Rapid, sensitive, and accurate detection of adenosine triphosphate (ATP), the primary energy molecule, is critical for the elucidation of its unique roles in cell signaling and many cellular reactions. Up to date, a major challenge is still remaining for fabricating surface-enhanced Raman scattering (SERS) aptamer sensors (aptasensors) suitable for accurate and reliable quantification of ATP. Herein, we develop the ratiometric silicon SERS aptasensor for ATP detection, which is made of uniform silver nanoparticles (Ag NPs)-modified silicon wafer (Ag NPs@Si), followed by the functionalization with double-stranded DNA (dsDNA I)...
September 21, 2017: Analytical Chemistry
Fabio Maroni, Gilberto Carbonari, Fausto Croce, Roberto Tossici, Francesco Nobili
The design of effective supporting matrices to efficiently cycle Si nanoparticles is often difficult to be achieved and requires complex preparation strategies. In this work, we present a simple synthesis of low-cost and environmentally benign Anatase-TiO2 nanoparticles as buffering filler for Si nanoparticles (Si@TiO2). Average anatase crystallite size is estimated in 5 nm. A complete structural, morphological and electrochemical characterization is performed. Electrochemical test results show very good specific capacity values around up to 1000 mAhg-1 and cycling at several specific currents, ranging from 500 mAg-1 to 2000 mAg-1, demonstrating a very good tolerance to high cycling rates...
September 7, 2017: ChemSusChem
David Beke, Gyula Károlyházy, Zsolt Czigány, Gábor Bortel, Katalin Kamarás, Adam Gali
Production of semiconductor nanostructures with high yield and tight control of shape and size distribution is an immediate quest in diverse areas of science and technology. Electroless wet chemical etching or stain etching can produce semiconductor nanoparticles with high yield but is limited to a few materials because of the lack of understanding the physical-chemical processes behind. Here we report a no-photon exciton generation chemistry (NPEGEC) process, playing a key role in stain etching of semiconductors...
September 6, 2017: Scientific Reports
A Solorio-Rodríguez, V Escamilla-Rivera, M Uribe-Ramírez, A Chagolla, R Winkler, C M García-Cuellar, A De Vizcaya-Ruiz
Nanoparticles are a promising cancer therapy for their use as drug carriers given their versatile functionalization with polyethylene glycol and proteins that can be recognized by overexpressed receptors in tumor cells. However, it has been suggested that in biological fluids, proteins cover nanoparticles, which gives the proteins a biological identity that could be responsible for unexpected biological responses: the so-called protein corona. A relevant biological event that is usually ignored in protein-corona formation is the interspecies differences in protein binding, which can be involved in the discrepancies observed in preclinical studies and the nanoparticle safety and efficiency...
September 21, 2017: Nanoscale
Sidi Huang, Venkata Sharat Parimi, Sili Deng, Srilakshmi Lingamneni, Xiaolin Zheng
Silicon (Si) particles are widely utilized as high-capacity electrodes for Li-ion batteries, elements for thermoelectric devices, agents for bio-imaging and therapy, and many other applications. However, Si particles can ignite and burn in air at elevated temperatures or under intense illumination. This poses potential safety hazards when handling, storing, and utilizing these particles for those applications. In order to avoid the problem of accidental ignition, it is critical to quantify the ignition properties of Si particles as functions of their sizes and porosities...
September 5, 2017: Nano Letters
Yichen Duan, Sana Rani, John T Newberg, Andrew V Teplyakov
Silver deposition precursor molecule trimethylphosphine(hexafluoroacetylacetonato)silver(I) [(hfac)AgP(CH3)3] was used to deposit silver onto water-modified (hydroxyl-terminated) solid substrates. A silicon wafer was used as a model flat surface, and water-predosed ZnO nanopowder was investigated to expand the findings to a common substrate material for possible practical applications. Following the deposition, oxygen plasma was used to remove the remaining organic ligands on a surface and to investigate its effect on the morphology of chemically deposited silver nanoparticles and films...
January 2018: Journal of Vacuum Science & Technology. A, Vacuum, Surfaces, and Films
Yoichi M A Yamada
My mission in catalysis research is to develop highly active and reusable supported catalytic systems in terms of fundamental chemistry and industrial application. For this purpose, I developed three types of highly active and reusable supported catalytic systems. The first type involves polymeric base-supported metal catalysts: Novel polymeric imidazole-Pd and Cu complexes were developed that worked at the mol ppm level for a variety of organic transformations. The second involves catalytic membrane-installed microflow reactors: Membranous polymeric palladium and copper complex/nanoparticle catalysts were installed at the center of a microtube to produce novel catalytic membrane-immobilized flow microreactor devices...
2017: Chemical & Pharmaceutical Bulletin
Joaquín Klug, María Fernanda Torresan, Florencia Lurgo, Graciela Borioli, Gabriela I Lacconi
We developed a highly sensitive silicon platform, suitable to assess the molecular organization of protein samples. Prototype platforms were obtained using different electrochemical protocols for the electrodeposition of Ag-nanoparticles onto the hydrogenated silicon surface. A platform with high Surface Enhanced Raman Scattering efficiency was selected based on the surface coverage and the number density of particles size distribution. The performance of the platform was determined by studying the interaction of Myristoylated Alanine-Rich C Kinase Substrate (MARCKS) protein with the substrate according to its molecular organization...
August 24, 2017: Journal of Colloid and Interface Science
Tomoo Sigehuzi
For the microscopic observation of nanoparticles, an adequate sample preparation is an essential part of this task. Much research has been performed for usable preparation methods that will yield aggregate-free samples. A freeze drying technique, which only requires a -80 (°)C freezer and a freeze dryer, is shown to provide an on-substrate dispersion of mostly isolated nanoparticles. The particle density could be made sufficiently high for efficient observations using atomic force microscopy. Since this sandwich method is purely physical, it could be applied to deposit various nanoparticles independent of their surface chemical properties...
August 28, 2017: Journal of Chemical Physics
David M Unuigbe, Margit Harting, Emmanuel O Jonah, David T Britton, Dennis Nordlund
The presence of native oxide on the surface of silicon nanoparticles is known to inhibit charge transport on the surfaces. Scanning electron microscopy (SEM) studies reveal that the particles in the printed silicon network have a wide range of sizes and shapes. High-resolution transmission electron microscopy reveals that the particle surfaces have mainly the (111)- and (100)-oriented planes which stabilizes against further oxidation of the particles. X-ray absorption spectroscopy (XANES) and X-ray photoelectron spectroscopy (XPS) measurements at the O 1s-edge have been utilized to study the oxidation and local atomic structure of printed layers of silicon nanoparticles which were milled for different times...
September 1, 2017: Journal of Synchrotron Radiation
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"