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Room Temperature Synthesis of Cu2O Nanospheres: Optical Properties and Thermal Behavior

Published online by Cambridge University Press:  21 October 2014

Daniela Nunes ,
Lídia Santos ,
Paulo Duarte ,
Ana Pimentel ,
Joana V. Pinto ,
Pedro Barquinha ,
Patrícia A. Carvalho ,
Elvira Fortunato  and
Rodrigo Martins
Daniela Nunes*
Affiliation:
Departamento de Ciência dos Materiais, CENIMAT/I3N, Faculdade de Ciências e Tecnologia (FCT) Universidade Nova de Lisboa and CEMOP-UNINOVA, 2829-516 Caparica, Portugal
Lídia Santos
Affiliation:
Departamento de Ciência dos Materiais, CENIMAT/I3N, Faculdade de Ciências e Tecnologia (FCT) Universidade Nova de Lisboa and CEMOP-UNINOVA, 2829-516 Caparica, Portugal
Paulo Duarte
Affiliation:
Departamento de Ciência dos Materiais, CENIMAT/I3N, Faculdade de Ciências e Tecnologia (FCT) Universidade Nova de Lisboa and CEMOP-UNINOVA, 2829-516 Caparica, Portugal
Ana Pimentel
Affiliation:
Departamento de Ciência dos Materiais, CENIMAT/I3N, Faculdade de Ciências e Tecnologia (FCT) Universidade Nova de Lisboa and CEMOP-UNINOVA, 2829-516 Caparica, Portugal
Joana V. Pinto
Affiliation:
Departamento de Ciência dos Materiais, CENIMAT/I3N, Faculdade de Ciências e Tecnologia (FCT) Universidade Nova de Lisboa and CEMOP-UNINOVA, 2829-516 Caparica, Portugal
Pedro Barquinha
Affiliation:
Departamento de Ciência dos Materiais, CENIMAT/I3N, Faculdade de Ciências e Tecnologia (FCT) Universidade Nova de Lisboa and CEMOP-UNINOVA, 2829-516 Caparica, Portugal
Patrícia A. Carvalho
Affiliation:
ICEMS, Instituto Superior Técnico, Universidade Técnica de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal
Elvira Fortunato*
Affiliation:
Departamento de Ciência dos Materiais, CENIMAT/I3N, Faculdade de Ciências e Tecnologia (FCT) Universidade Nova de Lisboa and CEMOP-UNINOVA, 2829-516 Caparica, Portugal
Rodrigo Martins*
Affiliation:
Departamento de Ciência dos Materiais, CENIMAT/I3N, Faculdade de Ciências e Tecnologia (FCT) Universidade Nova de Lisboa and CEMOP-UNINOVA, 2829-516 Caparica, Portugal
*
*Corresponding authors.ddsn.gomes@campus.fct.unl.pt; emf@fct.unl.pt; rm@uninova.pt
*Corresponding authors.ddsn.gomes@campus.fct.unl.pt; emf@fct.unl.pt; rm@uninova.pt
*Corresponding authors.ddsn.gomes@campus.fct.unl.pt; emf@fct.unl.pt; rm@uninova.pt
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Abstract

The present work reports a simple and easy wet chemistry synthesis of cuprous oxide (Cu2O) nanospheres at room temperature without surfactants and using different precursors. Structural characterization was carried out by X-ray diffraction, transmission electron microscopy, and scanning electron microscopy coupled with focused ion beam and energy-dispersive X-ray spectroscopy. The optical band gaps were determined from diffuse reflectance spectroscopy. The photoluminescence behavior of the as-synthesized nanospheres showed significant differences depending on the precursors used. The Cu2O nanospheres were constituted by aggregates of nanocrystals, in which an on/off emission behavior of each individual nanocrystal was identified during transmission electron microscopy observations. The thermal behavior of the Cu2O nanospheres was investigated with in situ X-ray diffraction and differential scanning calorimetry experiments. Remarkable structural differences were observed for the nanospheres annealed in air, which turned into hollow spherical structures surrounded by outsized nanocrystals.

Keywords

cuprous oxidenanospheresphotoluminescencecathodoluminescenceprecursor effectthermal behavior
Type
SPMicros Special Section
Information
Microscopy and Microanalysis , Volume 21 , Issue 1 , February 2015 , pp. 108 - 119
Copyright
© Microscopy Society of America 2014 

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