{"id":{"repo_id":"rice","oai_identifier":"oai:repository.rice.edu:1911/17841"},"canonical_url":"https://search.dev.ndltd.org/etd/rice/oai:repository.rice.edu:1911/17841","repository":{"repo_id":"rice","name":"Rice University","base_url":"https://repository.rice.edu/server/oai/request"},"display":{"title":"Controlled multi-step purification of single-walled carbon nanotubes","abstract":"A controlled and scalable multi-step purification method has been developed to remove iron impurity and non-nanotube carbon materials from raw single-walled carbon nanotubes produced in the HiPco (high pressure CO) process. In this study, iron nanoparticles, coated by carbon, are exposed and oxidized by multiple step oxidation at increasing temperatures. To avoid catalytic oxidation by iron oxide of carbon nanotubes, the exposed and oxidized iron oxide is deactivated by reaction with C2H2F4 or SF6. The iron fluorides are removed by a soxhlet extraction with a 6M HCl solution. The purity and quality of each sample were determined by thermo-gravimetric analysis (TGA), Raman spectrometry, ultraviolet-visible-near-IR (UV-vis-near-IR) spectrometry, fluorescence spectrometry and transmission electron microscope (TEM) spectroscopy. The purity and yield of SWNT are improved due to reduced catalytic activity of the iron oxide. Greater iron oxide removal also resulted from oxidation at higher temperatures.","abstract_html":"A controlled and scalable multi-step purification method has been developed to remove iron impurity and non-nanotube carbon materials from raw single-walled carbon nanotubes produced in the HiPco (high pressure CO) process. In this study, iron nanoparticles, coated by carbon, are exposed and oxidized by multiple step oxidation at increasing temperatures. To avoid catalytic oxidation by iron oxide of carbon nanotubes, the exposed and oxidized iron oxide is deactivated by reaction with C2H2F4 or SF6. The iron fluorides are removed by a soxhlet extraction with a 6M HCl solution. The purity and quality of each sample were determined by thermo-gravimetric analysis (TGA), Raman spectrometry, ultraviolet-visible-near-IR (UV-vis-near-IR) spectrometry, fluorescence spectrometry and transmission electron microscope (TEM) spectroscopy. The purity and yield of SWNT are improved due to reduced catalytic activity of the iron oxide. Greater iron oxide removal also resulted from oxidation at higher temperatures.","abstract_has_math":false,"creators":["Xu, Ya-Qiong"],"institution":"Rice University","degree_name":"Master of Science","degree_level":"Masters","degree_discipline":"Engineering","degree_department":null,"school":null,"contributors":[],"advisors":["Smalley, Richard E."],"committee_chairs":[],"committee_members":[],"year":2005,"date_issued":"2005","date_published":"2005","updated_at":"2026-07-24T04:10:32Z","subjects":["Electronics","Electrical engineering","Engineering","Materials science"],"languages":["eng"],"rights":["Copyright is held by the author, unless otherwise indicated. Permission to reuse, publish, or reproduce the work beyond the bounds of fair use or other exemptions to copyright law must be obtained from the copyright holder."],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://hdl.handle.net/1911/17841","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.advisor","label":"Advisor","values":["Smalley, Richard E."]},{"key":"dc:creator","label":"Author","values":["Xu, Ya-Qiong"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2009-06-04T06:57:02Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2009-06-04T06:57:02Z"]},{"key":"dc:date.issued","label":"Date","values":["2005"]},{"key":"dc:type","label":"Dc Type","values":["Thesis"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Engineering"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Masters"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Master of Science"]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["Rice University"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Electronics","Electrical engineering","Engineering","Materials science"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language.iso","label":"Language (ISO)","values":["eng"]},{"key":"dc:rights","label":"Dc Rights","values":["Copyright is held by the author, unless otherwise indicated. Permission to reuse, publish, or reproduce the work beyond the bounds of fair use or other exemptions to copyright law must be obtained from the copyright holder."]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["https://hdl.handle.net/1911/17841"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["A controlled and scalable multi-step purification method has been developed to remove iron impurity and non-nanotube carbon materials from raw single-walled carbon nanotubes produced in the HiPco (high pressure CO) process. In this study, iron nanoparticles, coated by carbon, are exposed and oxidized by multiple step oxidation at increasing temperatures. To avoid catalytic oxidation by iron oxide of carbon nanotubes, the exposed and oxidized iron oxide is deactivated by reaction with C2H2F4 or SF6. The iron fluorides are removed by a soxhlet extraction with a 6M HCl solution. The purity and quality of each sample were determined by thermo-gravimetric analysis (TGA), Raman spectrometry, ultraviolet-visible-near-IR (UV-vis-near-IR) spectrometry, fluorescence spectrometry and transmission electron microscope (TEM) spectroscopy. The purity and yield of SWNT are improved due to reduced catalytic activity of the iron oxide. Greater iron oxide removal also resulted from oxidation at higher temperatures."]},{"key":"dc:format.mimetype","label":"Dc Format Mimetype","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["Controlled multi-step purification of single-walled carbon nanotubes"]}]}],"canonical_facts":{"dc:contributor.advisor":["Smalley, Richard E."],"dc:creator":["Xu, Ya-Qiong"],"dc:date.accessioned":["2009-06-04T06:57:02Z"],"dc:date.available":["2009-06-04T06:57:02Z"],"dc:date.issued":["2005"],"dc:description.abstract":["A controlled and scalable multi-step purification method has been developed to remove iron impurity and non-nanotube carbon materials from raw single-walled carbon nanotubes produced in the HiPco (high pressure CO) process. In this study, iron nanoparticles, coated by carbon, are exposed and oxidized by multiple step oxidation at increasing temperatures. To avoid catalytic oxidation by iron oxide of carbon nanotubes, the exposed and oxidized iron oxide is deactivated by reaction with C2H2F4 or SF6. The iron fluorides are removed by a soxhlet extraction with a 6M HCl solution. The purity and quality of each sample were determined by thermo-gravimetric analysis (TGA), Raman spectrometry, ultraviolet-visible-near-IR (UV-vis-near-IR) spectrometry, fluorescence spectrometry and transmission electron microscope (TEM) spectroscopy. The purity and yield of SWNT are improved due to reduced catalytic activity of the iron oxide. Greater iron oxide removal also resulted from oxidation at higher temperatures."],"dc:format.mimetype":["application/pdf"],"dc:identifier.uri":["https://hdl.handle.net/1911/17841"],"dc:language.iso":["eng"],"dc:rights":["Copyright is held by the author, unless otherwise indicated. Permission to reuse, publish, or reproduce the work beyond the bounds of fair use or other exemptions to copyright law must be obtained from the copyright holder."],"dc:subject":["Electronics","Electrical engineering","Engineering","Materials science"],"dc:title":["Controlled multi-step purification of single-walled carbon nanotubes"],"dc:type":["Thesis"],"thesis:degree_discipline":["Engineering"],"thesis:degree_level":["Masters"],"thesis:degree_name":["Master of Science"],"thesis:institution_name":["Rice University"]},"updated_at":"2026-07-24T04:10:32Z"}