Development of Graphene based Cobaltferrites nanocomposites for microwave shielding

Abstract

In this study we developed graphene based cobalt ferrites composites by in situ co-precipitation route. Four samples were prepared with 0%, 0.1%, 0.5% and 1% graphene sheets to cobalt ferrites. The samples were characterized by XRD, and FTIR, while SEM was used to observe the hybrid structure of embed graphene sheets in cobalt ferrites. SEM confirms the successful adhesion of cobalt ferrites particles (10-20 nm) on graphene nano sheets, which are dispersed in metal oxide matrix. Microwave absorbing capacity of these samples was studied by Agilent network analyzer in low frequency band of microwave (1MHz to 2 GHz), Results reveals that graphene incorporation not only improved the absorption capacity of cobalt ferrites(13dB-17d), but also widened its maximum absorption peak. This change was supposed to be due to inhomogenity and combine effects of electric (graphene), and magnetic dielectric nature (cobalt ferrites). Further mechanical characterizations reveal that our composites samples have higher flexural strength (19.92 MPa for 1 % loading) and improved toughness (>6000 J/mm2) compare to pure cobalt ferrites (10.28 MPa, 1000 J/mm2).