Synthesis and DC Electrical Conductivity Studies of Multilayer Graphene/Zinc Oxide Nanowires Composite Foils

Flexible composite foils made up of multilayer graphene (MLG) and ZnO nanowires (ZnO-NW) are produced via vacuum filtration of acetone-based suspension. The sheet resistance and effective dc electrical conductivity of the foils, with increasing content of ZnO-NW over a fixed amount of MLG, is measured in order to investigate the effect of ZnO inclusion in MLG papers. An enhancement in the dc conductivity of the composite foils with respect to a plain MLG-foil is noticed only for very low amounts of ZnO loading. The peak conductivity of 16.8 kS/m, representing an increase of 31% with respect to the conductivity of a plain MLG-foil, is observed at the optimum concentration of 10%wt ZnO over the MLG content. This confirms the physical and electronic interaction at the interface between MLG and ZnO-NW. At higher concentration of ZnO-NW, a linear decay in the effective conductivity of the foils is observed.