uu.seUppsala University Publications
Change search
Link to record
Permanent link

Direct link
BETA
Wang, JunXin
Publications (6 of 6) Show all publications
Wang, J., Xu, C., Nilsson, A. M., Fernandes, D. L. A. & Niklasson, G. A. (2019). A novel phase function describing light scattering of layers containing colloidal nanospheres. Nanoscale, 11(15), 7404-7413
Open this publication in new window or tab >>A novel phase function describing light scattering of layers containing colloidal nanospheres
Show others...
2019 (English)In: Nanoscale, ISSN 2040-3364, E-ISSN 2040-3372, Vol. 11, no 15, p. 7404-7413Article in journal (Refereed) Published
Abstract [en]

Light scattering from small particles exhibit unique angular scattering distributions, which are strongly dependent on the radius to wavelength ratio as well as the refractive index contrast between the particles and the surrounding medium. As the concentration of the particles increases, multiple scattering becomes important. This complicates the description of the angular scattering patterns, and in many cases one has to resort to empirical phase functions. We have measured the angle dependence of light scattering from a polymer layer containing sub-micron metallic and dielectric particles. The samples exhibited strongly forward and backward peaked scattering patterns, which were fitted to a number of empirical approximative phase functions. We found that a novel two-term Reynolds-McCormick (TTRM) phase function gave the best fit to the experimental data in all cases. The feasibility of the TTRM approach was further validated by good agreement with numerical simulations of Mie single scattering phase functions at various wavelengths and sizes, ranging from the Rayleigh scattering regime to the geometrical optics regime. Hence, the widely adaptable TTRM approach is able to describe angular scattering distributions of different kinds of nanospheres and nanocomposites, both in the single scattering and multiple scattering regimes.

Place, publisher, year, edition, pages
ROYAL SOC CHEMISTRY, 2019
National Category
Physical Chemistry
Identifiers
urn:nbn:se:uu:diva-383188 (URN)10.1039/c9nr01707k (DOI)000465315900034 ()30938744 (PubMedID)
Funder
Swedish Research Council, 2016-03713
Available from: 2019-07-25 Created: 2019-07-25 Last updated: 2019-07-25Bibliographically approved
Wang, J. (2019). Angle dependent light scattering of functional nanoparticle composites. (Doctoral dissertation). Uppsala: Acta Universitatis Upsaliensis
Open this publication in new window or tab >>Angle dependent light scattering of functional nanoparticle composites
2019 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Varies functional nanoparticles play crucial roles in energy- and optical- related applications. The incorporation of functional nanoparticles into non-absorbing polymers to form optical absorption and scattering thin films have attracted considerable interest due to a successful selection of particles and matrices, synergistic effects of separation and fixation of particles, and controllable layer thicknesses and structures. To investigate the optical parameters, especially absorption and scattering coefficients of the nanocomposites, it is critical to evaluate and optimize those particle based functional layers.

In this thesis, we mainly focus on developing approaches for the inversion of scattering and absorption coefficients from optically measured transmittance and reflectance spectra. A two-flux radiative transfer model is robust for this purpose, but its limitation lies in failing to converge the transmittance and reflectance spectra to experimental data owing to the approximation of the completely diffuse scattering patterns. We carried out thorough characterization of angle- and wavelength-resolved light scattering on those nanocomposites with metallic Au, ferromagnetic Fe3O4 and photocatalytic TiO2 nanoparticles. We further developed an empirical scattering phase function, which can fully represent the scattering distributions for aggregated particles in the multiple scattering regime, as well as the single scattering in the Rayleigh, Mie and geometric optical scattering regimes. The incorporation of angle-resolved data into the two-flux theory to derive scattering and absorption coefficients have been validated using the functional nanoparticle composites. Several approximations are also proposed to obtain the scattering and absorption coefficients when angle resolved measurements were not available.

The optical performance was investigated on the nanocomposites mentioned above with varied sizes, shapes and concentrations using a spectrophotometer, an in-plane scatterometer and an out-of-plane goniometer. Single particle dark-field scattering spectra were also obtained for Au, Fe3O4, and TiO2 particles in the forward and backward directions.

Place, publisher, year, edition, pages
Uppsala: Acta Universitatis Upsaliensis, 2019. p. 89
Series
Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology, ISSN 1651-6214 ; 1767
Keywords
light scattering, nano particle, absorption, radiative transfer
National Category
Nano Technology
Research subject
Solid State Physics
Identifiers
urn:nbn:se:uu:diva-374319 (URN)978-91-513-0559-2 (ISBN)
Public defence
2019-03-08, Polhemsalen, Ångströmlaboratoriet, Lägerhyddsvägen 1, Uppsala, 13:15 (English)
Opponent
Supervisors
Available from: 2019-02-11 Created: 2019-01-21 Last updated: 2019-02-19
Wang, J., Xu, C., Nilsson, A. M., Fernandes, D. L. A., Strömberg, M., Wang, J. & Niklasson, G. (2018). General Method for Determining Light Scattering and Absorption of Nanoparticle Composites. Advanced Optical Materials, 6(4), Article ID 1801315.
Open this publication in new window or tab >>General Method for Determining Light Scattering and Absorption of Nanoparticle Composites
Show others...
2018 (English)In: Advanced Optical Materials, ISSN 2162-7568, E-ISSN 2195-1071, Vol. 6, no 4, article id 1801315Article in journal (Refereed) Published
Abstract [en]

Scattering and absorption from nanoparticles are of major importance in optical research as well as in a range of applications. The Kubelka–Munk two-flux radiative transfer model gives a simple description of light scattering in nanoparticle composite materials, but inversion of experimental transmittance and reflectance data to obtain backscattering and absorption coefficients remains challenging. Here, a general method for evaluating these parameters from transmittance and reflectance spectra, combined with spectral angle resolved light scattering measurements is developed. The angular dependence is approximatedby an extension of the empirical Reynolds–McCormick phase function, which is fitted to the experimental angle resolved light scattering data. This approach is verified by measurements on three typical nanoparticle/polymer composites containing plasmonic Au, ferromagnetic Fe3O4, and dielectric TiO2 particles. An approximation to the angular scattering pattern is further demonstrated, which can be applied to obtain the optical parameters using only reflectance and transmittance data, in cases where angle-resolved measurements are not available. These results can be extended to a wide range of isotropic, anisotropic, and multiple scattering systems, and will be highly useful in the fields of light scattering coatings/metamaterials, UV-shielding films, displays, absorption/scattering layers in solar cells and biological scatterers.

Place, publisher, year, edition, pages
Wiley-VCH Verlagsgesellschaft, 2018
National Category
Other Physics Topics Condensed Matter Physics
Research subject
Engineering Science with specialization in Solid State Physics
Identifiers
urn:nbn:se:uu:diva-370103 (URN)10.1002/adom.201801315 (DOI)000459020300005 ()
Funder
Swedish Research Council, 2016-03713Swedish Research Council Formas, 221-2012-444
Available from: 2018-12-19 Created: 2018-12-19 Last updated: 2019-08-01Bibliographically approved
Wang, J., Nilsson, A. M. & Niklasson, G. A. (2016). Light Scattering by 2D- and 3D- Angle-Resolved Spectroscopy. In: INERA Conference: Vapor Phase Technologies for Metal Oxide and Carbon Nanostructures: . Paper presented at INERA Conference: Vapor Phase Technologies for Metal Oxide and Carbon Nanostructures, Velingrad, Bulgaria, July 5-9, 2016.
Open this publication in new window or tab >>Light Scattering by 2D- and 3D- Angle-Resolved Spectroscopy
2016 (English)In: INERA Conference: Vapor Phase Technologies for Metal Oxide and Carbon Nanostructures, 2016Conference paper, Poster (with or without abstract) (Refereed)
National Category
Engineering and Technology
Research subject
Engineering Science with specialization in Solid State Physics
Identifiers
urn:nbn:se:uu:diva-307584 (URN)
Conference
INERA Conference: Vapor Phase Technologies for Metal Oxide and Carbon Nanostructures, Velingrad, Bulgaria, July 5-9, 2016
Available from: 2016-11-17 Created: 2016-11-17 Last updated: 2019-01-21Bibliographically approved
Wang, J., Nilsson, A. M., Fernandes, D. L. A. & Niklasson, G. A. (2015). Angle dependent light scattering by gold nanospheres. In: INERA Conference: Book of Abstracts. Paper presented at Light in Nanoscience and Nanotechnology, LNN 2015, October 20-22, 2015, Hissar, Bulgaria (pp. 71). , Article ID 012018.
Open this publication in new window or tab >>Angle dependent light scattering by gold nanospheres
2015 (English)In: INERA Conference: Book of Abstracts, 2015, p. 71-, article id 012018Conference paper, Poster (with or without abstract) (Refereed)
Abstract [en]

Gold nanocrystals exhibit unique optical properties in enhanced light absorption and scattering owing to their extremely large scattering/absorption cross. sections and large electric field enhancements generated by localized surface plasmon resonance. In this work, the optical properties of gold nanospheres with diameters of 60 nm and 200 nm with remarkable uniformity in size were studied both numerically and experimentally. The total transmittance and reflectance as well as the angle. resolved light scattering intensities of the gold nanospheres were measured. The absorption and scattering coefficients were obtained by fitting the experimental data to the two. flux theory and were in qualitative agreement with single. scattering calculations using the Mie theory.

Series
Journal of Physics Conference Series, ISSN 1742-6588 ; 682
National Category
Condensed Matter Physics Engineering and Technology
Identifiers
urn:nbn:se:uu:diva-266863 (URN)10.1088/1742-6596/682/1/012018 (DOI)000372173400018 ()
Conference
Light in Nanoscience and Nanotechnology, LNN 2015, October 20-22, 2015, Hissar, Bulgaria
Available from: 2015-11-12 Created: 2015-11-12 Last updated: 2019-01-21Bibliographically approved
Yang, J., Wang, J., Strömme, M. & Welch, K.Enhanced UV protection and water adsorption properties of transparent poly(methyl methacrylate) films through incorporation of amorphous magnesium carbonate nanoparticles.
Open this publication in new window or tab >>Enhanced UV protection and water adsorption properties of transparent poly(methyl methacrylate) films through incorporation of amorphous magnesium carbonate nanoparticles
(English)Manuscript (preprint) (Other academic)
National Category
Nano Technology
Identifiers
urn:nbn:se:uu:diva-354510 (URN)
Available from: 2018-06-20 Created: 2018-06-20 Last updated: 2019-01-21
Organisations

Search in DiVA

Show all publications