An arc-discharge method using a buffer gas containing carbon dioxide has been developed for the efficient and large-scale synthesis of few-layered graphene.The resulting samples of few-layered graphene,well-dispersed in organic solvents such as N,N-dimethylformamide(DMF)and 1,2-dichlorobenzene(o-DCB),were examined by transmission electron microscopy(TEM),X-ray diffraction(XRD),Raman spectroscopy,atomic force microscopy(AFM),and thermal gravimetric analysis(TGA).The electrical conductivity and transparency of flexible films prepared using a direct solution process have also been studied.
Flexible organic field-effect transistors(OFETs)using solution-processable functionalized graphene for all the electrodes(source,drain,and gate)have been fabricated for the first time.These OFETs show performance comparable to corresponding devices using Au electrodes as the source/drain electrodes on SiO2/Si substrates with Si as the gate electrode.Also,these devices demonstrate excellent flexibility without performance degradation over severe bending cycles.Furthermore,inverter circuits have been designed and fabricated using these all-graphene-electrode OFETs.Our results demonstrate that the long-sought dream for all-carbon and flexible electronics is now much closer to reality.
Yongsheng ChenYanfei XuKai ZhaoXiangjian WanJiachun DengWeibo Yan
A novel hybrid material prepared from graphene and poly(3,4-ethyldioxythiophene)(PEDOT)shows excellent transparency,electrical conductivity,and good flexibility,together with high thermal stability and is easily processed in both water and organic solvents.Conductivities of the order of 0.2 S/cm and light transmittance of greater than 80%in the 4001800 nm wavelength range were observed for fi lms with thickness of tens of nm.Practical applications in a variety of optoelectronic devices are thus expected for this transparent and flexible conducting graphene-based hybrid material。