AVALIAÇÃO DO PAPEL DO ÓXIDO DE GRAFENO (GO) NA GERAÇÃO FOTOCATALÍTICA DE HIDROGÊNIO EM SISTEMAS BINÁRIOS (GO-CdS) E TERNÁRIOS (Pt-GO-CdS)

Abstract

EVALUATION OF THE GRAPHENE OXIDE (GO) ROLE IN THE PHOTOCATALYTIC GENERATION OF HYDROGEN IN BINARY (GO-CdS) AND TERNARY (Pt-GO-CdS) SYSTEMS. Water splitting is a promising process to produce hydrogen from friendly feedstock and solar energy. In this work we have evaluated binary (GO-CdS) and ternary (Pt-GO-CdS) hybrid photocatalysts for hydrogen production assisted by visible light irradiation. Cadmium sulfide and composites with GO were prepared by sonochemical and thermal methods. GO addition took place by different strategies: during the synthesis or by mechanical mixture. A variety of configurations was tested and the best performance in hydrogen production among all materials was the ternary photocatalyst named Pt(GO/CdS TT), whose hydrogen production rate was 651 µmol g cat-1 h-1. Such material was obtained by thermal method with GO addition during the synthesis. Additionally, the XRD and Raman analyses have confirmed the GO photoreduction during photocatalytic hydrogen evolution.

Estudo das propriedades reológicas de nanofluidos à base de etilenoglicol e óxido de grafeno

“…Assim, para o preparo dos nanofluidos somente as porções contendo GO como sobrenadante foram utilizadas. Através da DRX também foi possível determinar o número de folhas médias do GO, utilizando a equação de Scherrer [29]. Segundo MARASCHIN et al [30], o número de folhas de grafeno presente no grafite e GO, pode ser calculado utilizando a razão da espessura do material pelo espaçamento entre as folhas de grafeno.…”