eprintid: 16738 rev_number: 14 userid: 1558 dir: disk0/00/01/67/38 datestamp: 2013-01-24 21:24:38 lastmod: 2016-11-15 14:07:56 status_changed: 2013-01-24 21:24:38 type: thesis_degree metadata_visibility: show contact_email: xic28@pitt.edu item_issues_count: 0 eprint_status: archive creators_name: Chao, Xing creators_email: xic28@pitt.edu creators_id: XIC28 title: CRYSTALLINE COLLOIDAL ARRAY FILTER AND RAMAN IMAGING ispublished: unpub divisions: sch_as_chemistry full_text_status: public keywords: crystalline colloidal arrays, photonic crystals, silica colloidal, polystyrene colloidal, UV Raman imaging, Raman spectroscopy, Rayleigh rejection filter, wavelength-selecting filter abstract: The background and diffraction theory of crystalline colloidal arrays (CCAs) are briefly reviewed. Crystalline colloidal arrays were fabricated by using silica particles and polystyrene (PS) particles for deep ultraviolet (UV) and visible regions, respectively. I used a modified Stöber method to synthesize small (<100 nm) silica particles. The silica particles were surface functionalized with a strong acid, non-UV absorbing silane coupling agent. PS particles were also synthesized with emulsion polymerization method. These monodisperse, highly charged particles self-assemble into face-centered cubic CCAs that show Bragg diffraction of UV and visible light. The diffraction wavelength was 248 nm for silica CCA filter at normal incidence. The PS CCAs diffracted 518 nm and 580 nm light at normal incidence. These CCA filters were tested with UV/vis/NIR spectrophotometer and lasers. UV/vis/NIR extinction showed high rejection efficiency and narrow diffraction bands. 244 nm argon laser light was used to study the transmission, reflection and scattering of the silica CCA filter. Teflon Raman scattering measurement was also performed with 244 nm light and a silica CCA filter used as the Rayleigh rejection filter. The filter rejected 99.91% of the Rayleigh scattering light. We attempted to develop a Raman imaging spectrometer. Towards this affect, I attempted to do fluorescence imaging by using 514.5 argon laser light with PS visible filters. Spectra of fluorescence bands and fluorescence images were recorded. date: 2013-01-24 date_type: published pages: 48 institution: University of Pittsburgh refereed: TRUE etdcommittee_type: committee_chair etdcommittee_type: committee_member etdcommittee_type: committee_member etdcommittee_name: Asher, Sanford A etdcommittee_name: Waldeck, David H etdcommittee_name: Rosi, Nathaniel L etdcommittee_email: asher@pitt.edu etdcommittee_email: dave@pitt.edu etdcommittee_email: nrosi@pitt.edu etdcommittee_id: ASHER etdcommittee_id: DAVE etdcommittee_id: NROSI etd_defense_date: 2012-11-19 etd_approval_date: 2013-01-24 etd_submission_date: 2012-12-03 etd_release_date: 2013-01-24 etd_access_restriction: immediate etd_patent_pending: FALSE thesis_type: thesis degree: MS citation: Chao, Xing (2013) CRYSTALLINE COLLOIDAL ARRAY FILTER AND RAMAN IMAGING. Master's Thesis, University of Pittsburgh. (Unpublished) document_url: http://d-scholarship-dev.library.pitt.edu/16738/1/Crystalline_Colloidal_Array_Filter_and_Raman_Imaging-final_edition-revised.pdf