{"corpus_id":98740600,"paper_sha":"af20e9db2ad36acd68db075d5690b9f43d00c6c2","doi":"10.1016/j.molcata.2004.03.032","arxiv_id":"1009.2926","pmid":null,"pmcid":null,"mag_id":2124341491,"dblp_id":null,"acl_id":null,"title":"Effect of annealing temperature on morphology, structure and photocatalytic behavior of nanotubed H2Ti2O4(OH)2","year":2004,"publication_date":"2004-08-03","venue":"","journal":{"name":"Journal of Molecular Catalysis A-chemical","pages":"203-210","volume":"217"},"journal_issn":null,"journal_title":null,"publication_types":[],"pubmed_pub_types":null,"s2_fields_of_study":["Physics","Materials Science","Chemistry"],"reference_count":23,"citation_count":305,"influential_citation_count":5,"is_open_access":true,"arxiv_categories":["cond-mat.mtrl-sci","cond-mat.mes-hall"],"arxiv_license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","arxiv_journal_ref":"Journal of Molecular Catalysis A: Chemical Volume 217, Issues 1-2,\n  3 August 2004, Pages 203-210","mesh_headings":null,"chemicals":null,"comments_corrections":null,"source_flags":1,"s2_open_access_pdf_url":"https://arxiv.org/pdf/1009.2926","s2_open_access_landing_url":"https://www.semanticscholar.org/paper/af20e9db2ad36acd68db075d5690b9f43d00c6c2","s2_open_access_license":null,"s2_open_access_status":"GREEN","pmc_open_access_pdf_url":null,"pmc_open_access_landing_url":null,"pmc_open_access_license":null,"pmc_open_access_status":null,"unpaywall_open_access_pdf_url":null,"unpaywall_open_access_landing_url":null,"unpaywall_open_access_license":null,"unpaywall_open_access_status":null,"abstract":"Abstract Nanotubed titanic acid (H2Ti2O4(OH)2) was prepared from nanotubed sodium titanate (Na2Ti2O4(OH)2) by an ion exchange reaction in a pH=1 HCl solution. The effect of annealing temperature on the morphology, structure and photocatalytic behavior of nanotubed H2Ti2O4(OH)2 was studied by means of TEM, XRD, DTG, DSC, BET and ESR. The results showed that nanotubed H2Ti2O4(OH)2 is thermally unstable. Its dehydration consists of two steps. In the first-step dehydration, single-electron-trapped oxygen vacancies (SETOVs) were generated. Accompanying the second-step dehydration, the transition of crystal form from orthorhombic system to anatase took place, at the same time the nanotubes broke. At T>300 °C, when the SETOV concentration greatly increased, the interaction between SETOV happened. (VOo)x formed could play the role of recombination center of photogenerated e−–h+ and make the photocatalytic behavior of TiO2 (anatase, obtained from 500 °C-treated nanotubed H2Ti2O4(OH)2) to become bad.","claims":[{"public_id":"cl_5ecc35aab04f5c31e57bdc90f5b61884","status":"active","text":"Above 300 °C, increasing single-electron-trapped oxygen vacancy concentration leads to vacancy interactions and formation of recombination centers that degrade the photocatalytic behavior of anatase TiO2 obtained at 500 °C.","confidence":0.92,"contributors":[{"id":1,"public_id":"12632b8b5f","public_label":"Anonymous (12632b8b5f)","roles":["extraction"],"url":"https://sah.borca.ai/u/12632b8b5f"}],"url":"https://sah.borca.ai/claims/cl_5ecc35aab04f5c31e57bdc90f5b61884"},{"public_id":"cl_e95602dd0af61b6e9e6dfdda1fa62d79","status":"active","text":"Dehydration of nanotubed H2Ti2O4(OH)2 occurs in two steps.","confidence":0.95,"contributors":[{"id":1,"public_id":"12632b8b5f","public_label":"Anonymous 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