scholarly journals Real-time synthesis and detection of plasmonic metal (Au, Ag) nanoparticles under monochromatic X-ray nano-tomography

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Amardeep Bharti ◽  
Keun Hwa Chae ◽  
Navdeep Goyal

AbstractPlasmonic nanostructures are of immense interest of research due to its widespread applications in microelectronics, photonics, and biotechnology, because of its size and shape-dependent localized surface plasmon resonance response. The great efforts have been constructed by physicists, chemists, and material scientists to deliver optimized reaction protocol to tailor the size and shape of nanostructures. Real-time characterization emerges out as a versatile tool in perspective to the optimization of synthesis parameters. Moreover, in the past decades, radiation-induced reduction of metallic-salt to nanoparticles dominates over the conventional direct chemical reduction process which overcomes the production of secondary products and yields ultra-high quality and pure nanostructures. Here we show, the real-time/in-situ synthesis and detection of plasmonic (Au andAg) nanoparticles using single synchrotron monochromatic 6.7 keV X-rays based Nano-Tomography beamline. The real-time X-ray nano-tomography of plasmonic nanostructures has been first-time successfully achieved at such a low-energy that would be leading to the possibility of these experiments at laboratory-based sources. In-situ optical imaging confirms the radiolysis of water molecule resulting in the production of $$e_{aq}^-,\,OH^\bullet ,$$ e aq - , O H ∙ , and $$O_2^-$$ O 2 - under X-ray irradiation. The obtained particle-size and size-distribution by X-ray tomography are in good agreement to TEM results. The effect of different chemical environment media on the particle-size has also been studied. This work provides the protocol to precisely control the size of nanostructures and to synthesize the ultrahigh-purity grade monodisperse nanoparticles that would definitely enhance the phase-contrast in cancer bio-imaging and plasmonic photovoltaic application.

2017 ◽  
Vol 24 (6) ◽  
pp. 1209-1217 ◽  
Author(s):  
Amardeep Bharti ◽  
Ashish K. Agrawal ◽  
Balwant Singh ◽  
Sanjeev Gautam ◽  
Navdeep Goyal

Plasmonic metal nanostructures have a significant impact on a diverse domain of fields, including photocatalysis, antibacterial, drug vector, biosensors, photovoltaic cell, optical and electronic devices. Metal nanoparticles (MNps) are the simplest nanostructure promising ultrahigh stability, ease of manufacturing and tunable optical response. Silver nanoparticles (AgNp) dominate in the class of MNps because of their relatively high abundance, chemical activity and unique physical properties. Although MNps offer the desired physical properties, most of the synthesis and fabrication methods lag at the electronic grade due to an unbidden secondary product as a result of the direct chemical reduction process. In this paper, a facile protocol is presented for fabricating high-yield in situ plasmonic AgNps under monochromatic X-rays irradiation, without the use of any chemical reducing agent which prevents the formation of secondary products. The ascendancy of this protocol is to produce high quantitative yield with control over the reaction rate, particle size and localized surface plasmon resonance response, and also to provide the feasibility for in situ characterization. The role of X-ray energy, beam flux and integrated dose towards the fabrication of plasmonic nanostructures has been studied. This experiment extends plasmonic research and provides avenues for upgrading production technologies of MNps.


MRS Bulletin ◽  
1999 ◽  
Vol 24 (1) ◽  
pp. 21-25 ◽  
Author(s):  
G. Brian Stephenson ◽  
Jeffrey A. Eastman ◽  
Orlando Auciello ◽  
Anneli Munkholm ◽  
Carol Thompson ◽  
...  

Vapor-phase processes such as chemical vapor deposition (CVD) and reactive ion etching are the primary methods for the production-scale synthesis and processing of many high-quality thin-film materials. For example, these processes are widely used in the microelectronics industry for synthesis and lithography of the various semiconducting, insulating, and conducting layers in devices. Understanding the means of controlling the microstructure and composition of these materials is of great technological interest. However a difficulty often encountered in developing vapor-phase processes is an undesirable dependence on trial-and-error methods for optimizing the many process parameters. These parameters include gas composition, flow rate, pressure, and substrate temperature, all of which are typically changing with time. This reliance on empirical methods can be attributed to the tremendous chemical and physical complexity of vapor-phase processes and the lack of appropriate in situ measurement techniques for the vapor-phase environment.We have initiated a program to apply synchrotron x-ray analysis techniques as real-time probes of film and surface structure during vapor-phase processing. X-rays have a combination of properties which makes them particularly well-suited for these studies. Unlike electrons, x-rays have a sufficiently low absorption to penetrate vapor-phase processing environments and chamber walls. Unlike visible light, x-rays have wavelengths and energies suitable for study of atomic-scale structure and chemistry. A growing number of in situ synchrotron x-ray investigations of film growth and processing demonstrate the power of these techniques.


Minerals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 426
Author(s):  
Behrooz Abbasi ◽  
Xiaoliang Wang ◽  
Judith C. Chow ◽  
John G. Watson ◽  
Bijan Peik ◽  
...  

Respirable coal mine dust (RCMD) exposure is associated with black lung and silicosis diseases in underground miners. Although only RCMD mass and silica concentrations are regulated, it is possible that particle size, surface area, and other chemical constituents also contribute to its adverse health effects. This review summarizes measurement technologies for RCMD mass concentrations, morphology, size distributions, and chemical compositions, with examples from published efforts where these methods have been applied. Some state-of-the-art technologies presented in this paper have not been certified as intrinsically safe, and caution should be exerted for their use in explosive environments. RCMD mass concentrations are most often obtained by filter sampling followed by gravimetric analysis, but recent requirements for real-time monitoring by continuous personal dust monitors (CPDM) enable quicker exposure risk assessments. Emerging low-cost photometers provide an opportunity for a wider deployment of real-time exposure assessment. Particle size distributions can be determined by microscopy, cascade impactors, aerodynamic spectrometers, optical particle counters, and electrical mobility analyzers, each with unique advantages and limitations. Different filter media are required to collect integrated samples over working shifts for comprehensive chemical analysis. Teflon membrane filters are used for mass by gravimetry, elements by energy dispersive X-ray fluorescence, rare-earth elements by inductively coupled plasma-mass spectrometry and mineralogy by X-ray diffraction. Quartz fiber filters are analyzed for organic, elemental, and brown carbon by thermal/optical methods and non-polar organics by thermal desorption-gas chromatography-mass spectrometry. Polycarbonate-membrane filters are analyzed for morphology and elements by scanning electron microscopy (SEM) with energy dispersive X-ray, and quartz content by Fourier-transform infrared spectroscopy and Raman spectroscopy.


2013 ◽  
Vol 712-715 ◽  
pp. 293-297
Author(s):  
Li Li

Pt/Bi3.15Nd0.85Ti3O12(BNT)/Pt ferroelectric capacitors were monitored using in situ X-ray irradiation with 10 keV at BL14B1 beamline (Shanghai Synchrotron Radiation Facility). BL14B1 combined with a ferroelectric analyzer enabled measurements in situ of electrical performance. The hysteresis curve (PE) of distortion depended on the polarization during irradiation, but the diffracted intensities of the (117) peak did not change in the beginning. ThePEcurve had a negligible change from 2.09×109Gy to 4.45×109Gy. Finally, bothPrandPr+very rapidly increased, but the intensities of (117) decreased. The hysteresis loops were remarkably deformed at the maximum total dose of 4.87×109Gy.


2007 ◽  
Vol 130 ◽  
pp. 7-14 ◽  
Author(s):  
Andrew N. Fitch

The highly-collimated, intense X-rays produced by a synchrotron radiation source can be harnessed to build high-resolution powder diffraction instruments with a wide variety of applications. The general advantages of using synchrotron radiation for powder diffraction are discussed and illustrated with reference to the structural characterisation of crystalline materials, atomic PDF analysis, in-situ and high-throughput studies where the structure is evolving between successive scans, and the measurement of residual strain in engineering components.


2018 ◽  
Vol 9 (23) ◽  
pp. 6750-6754 ◽  
Author(s):  
Alessandro Greco ◽  
Alexander Hinderhofer ◽  
M. Ibrahim Dar ◽  
Neha Arora ◽  
Jan Hagenlocher ◽  
...  

2020 ◽  
Vol 61 (6) ◽  
Author(s):  
C E Schrank ◽  
K Gioseffi ◽  
T Blach ◽  
O Gaede ◽  
A Hawley ◽  
...  

Abstract We present a review of a unique non-destructive method for the real-time monitoring of phase transformations and nano-pore evolution in dehydrating rocks: transmission small- and wide-angle synchrotron X-ray scattering (SAXS/WAXS). It is shown how SAXS/WAXS can be applied to investigating rock samples dehydrated in a purpose-built loading cell that allows the coeval application of high temperature, axial confinement, and fluid pressure or flow to the specimen. Because synchrotron sources deliver extremely bright monochromatic X-rays across a wide energy spectrum, they enable the in situ examination of confined rock samples with thicknesses of ≤ 1 mm at a time resolution of order seconds. Hence, fast kinetics with reaction completion times of about hundreds of seconds can be tracked. With beam sizes of order tens to hundreds of micrometres, it is possible to monitor multiple interrogation points in a sample with a lateral extent of a few centimetres, thus resolving potential lateral spatial effects during dehydration and enlarging sample statistics significantly. Therefore, the SAXS/WAXS method offers the opportunity to acquire data on a striking range of length scales: for rock samples with thicknesses of ≤ 10-3 m and widths of 10-2 m, a lateral interrogation-point spacing of ≥ 10-5 m can be achieved. Within each irradiated interrogation-point volume, information concerning pores with sizes between 10-9 and 10-7 m and the crystal lattice on the scale of 10-10 m is acquired in real time. This article presents a summary of the physical principles underpinning transmission X-ray scattering with the aim of providing a guide for the design and interpretation of time-resolved SAXS/WAXS experiments. It is elucidated (1) when and how SAXS data can be used to analyse total porosity, internal surface area, and pore-size distributions in rocks on length scales from ∼1 to 300 nm; (2) how WAXS can be employed to track lattice transformations in situ; and (3) which limitations and complicating factors should be considered during experimental design, data analysis, and interpretation. To illustrate the key capabilities of the SAXS/WAXS method, we present a series of dehydration experiments on a well-studied natural gypsum rock: Volterra alabaster. Our results demonstrate that SAXS/WAXS is excellently suited for the in situ tracking of dehydration kinetics and the associated evolution of nano-pores. The phase transformation from gypsum to bassanite is correlated directly with nano-void growth on length scales between 1 and 11 nm for the first time. A comparison of the SAXS/WAXS kinetic results with literature data emphasises the need for future dehydration experiments on rock specimens because of the impact of rock fabric and the generally heterogeneous and transient nature of dehydration reactions in nature. It is anticipated that the SAXS/WAXS method combined with in situ loading cells will constitute an invaluable tool in the ongoing quest for understanding dehydration and other mineral replacement reactions in rocks quantitatively.


1995 ◽  
Vol 10 (3) ◽  
pp. 173-177 ◽  
Author(s):  
P. Ballirano ◽  
A. Maras ◽  
R. Caminiti ◽  
C. Sadun

New powder X-ray data for cancrinite [ideally Na8Si6Al6O24 (CO3)2·2 H2O] are reported along with in-situ real-time thermal processes recorded using energy dispersive X-ray diffractometry (EDXD). A completely anhydrous phase is obtained after heating the sample up to 600 °C and quickly cooling it to room temperature, as shown by means of both Rietveld analysis and IR spectroscopy. The anhydrous phase does not show any tendency to re-acquire molecular water. During the heating process, at around 450 °C, a peak splitting is observed, possibly due to a reversible phase transition.


Author(s):  
Weinong W. Chen ◽  
Matthew C. Hudspeth ◽  
Ben Claus ◽  
Niranjan D. Parab ◽  
John T. Black ◽  
...  

Split Hopkinson or Kolsky bars are common high-rate characterization tools for dynamic mechanical behaviour of materials. Stress–strain responses averaged over specimen volume are obtained as a function of strain rate. Specimen deformation histories can be monitored by high-speed imaging on the surface. It has not been possible to track the damage initiation and evolution during the dynamic deformation inside specimens except for a few transparent materials. In this study, we integrated Hopkinson compression/tension bars with high-speed X-ray imaging capabilities. The damage history in a dynamically deforming specimen was monitored in situ using synchrotron radiation via X-ray phase contrast imaging. The effectiveness of the novel union between these two powerful techniques, which opens a new angle for data acquisition in dynamic experiments, is demonstrated by a series of dynamic experiments on a variety of material systems, including particle interaction in granular materials, glass impact cracking, single crystal silicon tensile failure and ligament–bone junction damage.


Sign in / Sign up

Export Citation Format

Share Document