Surface excess on MgO-doped TiO2 nanoparticles

Author(s)

D. Gouvêa ^[1] ; B. H. Viana ^[2] ; J. Miagava ^[3]

Affiliation

^[1] Universidade de S. Paulo. Departamento de Engenharia Metalúrgica e de Materiais. Laboratório de Processos Cerâmicos - Brasil

^[2] Universidade de S. Paulo. Departamento de Engenharia Metalúrgica e de Materiais. Laboratório de Processos Cerâmicos - Brasil

^[3] Universidade de S. Paulo. Departamento de Engenharia Metalúrgica e de Materiais. Laboratório de Processos Cerâmicos - Brasil

• Document type: Journal article
• Source: Cerâmica; v. 62, n. 364, p. 400-404, 2016-12-00.

Abstract

Abstract Anatase has been the subject of several recent investigations partly as consequence of its interesting catalytic properties. Additives such as MgO have been introduced to improve the performance of the photocatalytic TiO2. However, the physical-chemistry of these oxides systems and their relationship with properties are poorly understood. In this work, nanoparticles of xMgO-(1-x)TiO2 (0≤ x≤ 0.05) were synthesized by the polymeric precursor method at 500 °C for 15 h. XRD results showed that only anatase phase was obtained and the crystallite size decreases with increased MgO concentration. Magnesia surface excess was calculated by washing powders with HNO3 and the soluble Mg ions concentration determined by chemical analysis. FTIR analysis confirms that the acid washing modified the particle surface. Therefore, it is proposed that the reduction of the crystallite size occurs due to segregation of MgO on TiO2 nanoparticles surfaces. (AU)

• FAPESP's process: 13/23134-2 - Surface segregation of MgO on TiO2 nanoparticles and its relationship with particle phases stability
• Grantee: Bhernardo Henrique Viana
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• FAPESP's process: 13/23209-2 - Ions segregation onto oxide nanopowders surfaces and the influence on the colloidal processing
• Grantee: Douglas Gouvêa
• Support Opportunities: Regular Research Grants