eprintid: 8359 rev_number: 5 userid: 6 dir: disk0/00/00/83/59 datestamp: 2011-11-10 19:51:03 lastmod: 2016-11-15 13:45:50 status_changed: 2011-11-10 19:51:03 type: thesis_degree metadata_visibility: show contact_email: nzn1@pitt.edu item_issues_count: 0 eprint_status: archive creators_name: Nioradze, Nikoloz creators_email: nzn1@pitt.edu creators_id: NZN1 title: DEVELOPMENT OF NANOFABRICATED PROBES FOR SCANNING ELECTROCHEMICAL MICROSCOPY ispublished: unpub divisions: sch_as_chemistry full_text_status: public keywords: mass transport rates; steady-state diffusion profiles abstract: ABSTRACTNikoloz Nioradze, MSUniversity of Pittsburgh 2009The work describes development of novel Pt disk electrodes with nanometer diameters using focused ion beam (FIB) milling. The nanofabricated electrodes are applied as probes of scanning electrochemical microscopy (SECM) for studying of electrochemical processes on redox reactive substrates. Nanotips are fabricated by pulling a platinum wire sealed in a glass capillary using a laser pipette puller. An inlaid platinum disk eventually is exposed by milling the tip of a pulled capillary by FIB. Electrodes are as small as 300-500 nm in diameter with a ratio of insulating glass sheath and Pt wire (RG) as small as 3. Moreover, FIB milling gives a flat tip surface. The small RG and smooth surface are helpful for approaching a probe close to a substrate in SECM feedback experiments. Nanometer-sized electrodes can be readily positioned within 100 nm from a polished platinum surface. After placing the tip close to the Pt disk, a potential of the Pt substrate is swept to drive a redox reaction, which is monitored as a current response at the nanometer-sized electrode. Presented method of combination of SECM and substrate cyclic voltammetry (CV) will allow for accurate extraction of electrochemical kinetic parameters of a redox reaction. Overall, it can be concluded that tips fabricated by presented method can be successfully exploited for SECM experiments. Described SECM-substrate CV approach will be useful for monitoring of electrochemical behavior of different conductive substrates. date: 2010-09-20 date_type: completed institution: University of Pittsburgh refereed: TRUE etdcommittee_type: committee_chair etdcommittee_type: committee_member etdcommittee_type: committee_member etdcommittee_name: Amemiya, Shigeru etdcommittee_name: Michael, Adrian etdcommittee_name: Waldeck, David etdcommittee_email: amemiya@pitt.edu etdcommittee_email: amichael@pitt.edu etdcommittee_email: dave@pitt.edu etdcommittee_id: AMEMIYA etdcommittee_id: AMICHAEL etdcommittee_id: DAVE etd_defense_date: 2009-11-24 etd_approval_date: 2010-09-20 etd_submission_date: 2010-07-13 etd_access_restriction: 5_year etd_patent_pending: FALSE assigned_doi: doi:10.5195/pitt.etd.2011.8359 thesis_type: thesis degree: MS committee: Shigeru Amemiya (amemiya@pitt.edu) - Committee Chair committee: Adrian Michael (amichael@pitt.edu) - Committee Member committee: David Waldeck (dave@pitt.edu) - Committee Member etdurn: etd-07132010-181621 other_id: http://etd.library.pitt.edu/ETD/available/etd-07132010-181621/ other_id: etd-07132010-181621 citation: Nioradze, Nikoloz (2010) DEVELOPMENT OF NANOFABRICATED PROBES FOR SCANNING ELECTROCHEMICAL MICROSCOPY. Master's Thesis, University of Pittsburgh. (Unpublished) document_url: http://d-scholarship-dev.library.pitt.edu/8359/1/N_NIORADZE_3.pdf