Enhanced Field Emission from Reduced Graphene Oxide Polymer Composites

Results on electron field emission (FE) from reduced graphene oxide (rGO):poly(3-hexylthiophene) (P3HT) composite layers are presented. Three different FE cathodes were tested and compared: rGO layers on (a) n(+)-Si, (b) composite films with different rGO:P3HT ratios, (c) rGO layers on composite films with different rGO:P3HT ratios. Experiments show that there is a critical rGO:P3HT ratio in which the field-emission performance is remarkably improved. Notably, such performance is always superior to that of the optimum rGO/n(+)-Si cathode. On the contrary, it is inferior to that attained upon deposition of a second rGO layer on top of the rGO:P3HT composite showed the best FE performance that showed turn-on field of as low as similar to 0.9 V/mu m and field enhancement factor of similar to 1900. The contributions of the composite film morphology as well as the role of rGO sheet substrate interaction on the emission performance are evaluated and discussed.