EXAFS and DFT study of the cadmium and lead adsorption on modified silica nanoparticles

Silica nanoparticles of 7 nm diameter were modified with (3-aminopropyl) triethoxysilane (APTES) and characterized by CP-MAS <sup>13</sup>C and <sup>29</sup>Si NMR, FTIR, zeta potential measurements, and thermogravimetry. The particles were shown to sorb successfully divalent...

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Detalhes bibliográficos
Autores: Arce, Valeria Beatriz, Gargarello, Romina M., Ortega, Florencia, Romañano, Virginia, Mizrahi, Martín D., Ramallo López, José Martín, Cobos, Carlos Jorge, Airoldi, Claudio, Bernardelli, Cecilia Elena, Donati, Edgardo Rubén, Mártire, Daniel Osvaldo
Formato: artículo
Estado:Versión publicada
Fecha de publicación:2015
País:Argentina
Recursos:Universidad Nacional de La Plata
Repositorio:SEDICI (UNLP)
Idioma:inglés
OAI Identifier:oai:sedici.unlp.edu.ar:10915/108444
Acesso em linha:http://sedici.unlp.edu.ar/handle/10915/108444
Access Level:acceso abierto
Palavra-chave:Ciencias Exactas
Cadmium
Lead
Silica nanoparticles
EXAFS
DFT
MEH-PPV
Descrição
Resumo:Silica nanoparticles of 7 nm diameter were modified with (3-aminopropyl) triethoxysilane (APTES) and characterized by CP-MAS <sup>13</sup>C and <sup>29</sup>Si NMR, FTIR, zeta potential measurements, and thermogravimetry. The particles were shown to sorb successfully divalent lead and cadmium ions from aqueous solution. Lead complexation with these silica nanoparticles was clearly confirmed by EXAFS (Extended X-ray Absorption Fine Structure) with synchrotron light measurements. Predicted Pb–N and Pb–C distances obtained from quantum-chemical calculations are in very good agreement with the EXAFS determinations. The calculations also support the higher APTES affinity for Pb<sup>2+</sup> compared to Cd<sup>2+</sup>.