Synthesis of Novel Periodic Mesoporous Organosilicas Containing 1,4,5,8-Naphthalenediimides within the Pore Walls and Their Reduction To Generate Wall-Embedded Free Radicals

Autor(es)

Castanheira, Bruna ^[1] ; Triboni, Eduardo Resende ^[2] ; Andrade, Luana dos Santos ^[3] ; Trindade, Fabiane de Jesus ^[1] ; Otubo, Larissa ^[4] ; Silva Costa Teixeira, Antonio Carlos ^[1] ; Politi, Mario Jose ^[5] ; de Queiroz, Thiago Branquinho ^[6] ; Brochsztain, Sergio ^[3]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Dept Engn Quim, BR-05508070 Sao Paulo - Brazil

^[2] Univ Sao Paulo, Escola Engn Lorena, BR-05508070 Sao Paulo - Brazil

^[3] Univ Fed ABC, Ctr Engn Modelagem & Ciencias Sociais Aplicadas, Ave Estados, BR-09210170 Santo Andre - Brazil

^[4] Inst Pesquisas Energet & Nucl, BR-05508000 Sao Paulo - Brazil

^[5] Univ Sao Paulo, Inst Quim, BR-05508070 Sao Paulo - Brazil

^[6] Univ Fed ABC, Ctr Ciencias Nat & Humanas, BR-09210580 Santo Andre - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Langmuir; v. 34, n. 28, p. 8195-8204, JUL 17 2018.
• Citações Web of Science: 1

Resumo

Novel periodic mesoporous organosilicas (PMOs) containing 1,4,5,8-Naphthalenediimide (NDI) chromophores as an integral part of the pore walls were synthesized in acidic conditions, in the presence of inorganic tetraethyl orthosilicate, using triblock copolymer surfactant Pluronic P-123 as a template. The NDI precursor, the bridged silsesquioxane N,N'-bis (3-triethoxysilylpropyl)- 1,4,5,8-naphthalenediimide, was synthesized by reaction of 1,4,5,8-naphthalenetetracarboxylic dianhydride with excess 3-aminopropyltriethoxysilane. A series of samples containing up to 19% (weight %) of NDI were prepared (the materials were labeled PMONDIs). C-13 and Si-29 solid-state nuclear magnetic resonance revealed that the NDI moiety was intact in the PMONDIs and efficiently grafted to the silica network. Samples with up to 16% NDI load presented an ordered two-dimensional-hexagonal mesoscopic structure, according to small-angle X-ray scattering, transmission electron microscopy, and nitrogen adsorption isotherms. Fluorescence spectra of the PMONDIs showed excimer formation upon excitation, suggesting high flexibility of the organic moieties. Reduction of PMONDIs with aqueous sodium dithionite led to the formation of wall-embedded NDI anion radicals, as observed by the appearance of new visible/near-infrared absorption bands. The PMONDIs were also shown to be efficient photocatalysts in the degradation of sulfadiazine, an antibiotic selected here as a model pollutant, which is usually present in water bodies and wastewater. (AU)

• Processo FAPESP: 15/06064-6 - Moléculas orgânicas funcionais e óxidos inorgânicos para o desenvolvimento de novos materiais
• Beneficiário: Eduardo Rezende Triboni
• Linha de fomento: Auxílio à Pesquisa - Regular
• Processo FAPESP: 16/05496-2 - Síntese e caracterização de organosílicas mesoporosas contendo imidas aromáticas e suas aplicações na área de energia
• Beneficiário: Sergio Brochsztain
• Linha de fomento: Auxílio à Pesquisa - Regular
• Processo FAPESP: 17/13839-0 - Sistemas orgânicos e inorgânicos para a preparação de meso e nanoestruturas
• Beneficiário: Eduardo Rezende Triboni
• Linha de fomento: Auxílio à Pesquisa - Regular