Sonochemically Assembled Photoluminescent Copper-Modified Graphene Oxide Microspheres

Darya Radziuk; Lubov Mikhnavets; Anastasia Tkach; Ludmila Tabulina; Vladimir Labunov

doi:10.1021/acs.langmuir.8b01557

Sonochemically Assembled Photoluminescent Copper-Modified Graphene Oxide Microspheres

Langmuir. 2018 Jul 24;34(29):8599-8610. doi: 10.1021/acs.langmuir.8b01557. Epub 2018 Jul 13.

Authors

Darya Radziuk¹, Lubov Mikhnavets¹, Anastasia Tkach¹, Ludmila Tabulina¹, Vladimir Labunov¹

Affiliation

¹ Laboratory of Integrated Micro- and Nanosystems , Belarusian State University of Informatics and Radioelectronics , 6 P. Brovki Street , Minsk 220013 , Belarus.

PMID: 29961327
DOI: 10.1021/acs.langmuir.8b01557

Abstract

A new accessible sonochemical assembly method is developed for the preparation of photoluminescent oil-filled silica@CuS/Cu₂O/CuO-graphene oxide (GO) microspheres that emit light of green, yellow, and red colors. This method is based on the ultrasonic emulsification of a biphasic mixture consisting of CuS/Cu₂O/CuO-graphene oxide (GO) nanocomposites with poly(vinyl alcohol) (PVA) (aqueous phase) and tetraethyl orthosilicate with sunflower oil (organic phase). CuS/Cu₂O/CuO-GO nanocomposites are composed of sonochemically formed three phases of copper: covellite CuS (p-type semiconductor), cuprite Cu₂O (Bloch p-type semiconductor), and CuO (charge-transfer insulator). The photoluminescence properties of microspheres result from H-bridging between PVA and CuS/Cu₂O/CuO-GO nanostructures, light absorption ability of Cu₂O, and charge-transfer insulation by CuO. Substitution of PVA by S-containing methylene blue quenches fluorescence by enhanced dye adsorption on CuS/Cu₂O/CuO-GO because of CuS and induced charge transfer. Non-S-containing malachite green is in a nonionized form and tends to be in the oil phase, prohibiting the charge transfer on CuS/Cu₂O/CuO-GO.

Publication types

Research Support, Non-U.S. Gov't