Enhancement of the photocatalytic activity and white emission of CaIn2O4 nanocrystals

• Autor(a) principal: Paskocimas, Carlos Alberto
• Data de Publicação: 2016
• Outros Autores: Melo, M. M., Araújo, Vinícius Dantas, Tranquilin, Ricardo Luis, Almeida, Cláudio Romero Rodrigues de, Delmonte, Maurício Roberto Bomio, Tavares, Mara T. S., Silva, Elson Longo da, Motta, Fabiana Villela da
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UFRN
• Texto Completo: https://repositorio.ufrn.br/handle/123456789/32276
• topic: CaIn2O4; Ultrasonic spray pyrolysis; Nanocrystals; Photocatalysis; Photoluminescence; White-light

CaIn2O4 (CIO) nanocrystals (NCs) were prepared by ultrasonic spray pyrolysis at 1223 K without the use of surfactants to investigate the influences of the nanostructure on the photoluminescence and photo-catalytic properties of this white-light emitter. The optical properties were analyzed by ultraviolet evisible (UVevis) absorption spectroscopy, which indicated a band gap energy of 3.83 eV, and photo-luminescence (PL) measurements at room temperature that showed a broad and intense emission band. X-ray diffraction (XRD) analysis confirmed that the CIO NCs adopted the orthorhombic crystalline phase. Field-emission gun scanning electron microscopy (FEG-SEM) micrographs demonstrated the spherical morphology of the CIO NCs, comprising aggregates of several CIO NCs. Furthermore, the as-synthesized CIO NCs exhibited enhanced activity for the photodegradation of methylene blue (MB) under UVevis irradiation. The chromaticity coordinates were calculated for the sample based on the PL spectrum; the CIO NCs had values of x 1⁄4 0.31 and y 1⁄4 0.38, and this point is located on the white region of the CIE diagram. Ultrasonic spray pyrolysis provides a feasible approach for preparing shape- and size-controlled CIO nanocrystals that hold great potential for photocatalytic applications and as photoluminescent white emitters