Green synthesis of reduced graphene oxide paper using Zn powder for supercapacitors

A green and simple approach was demonstrated to prepare reduced graphene oxide (rGO) paper using Zn powder in ammonia solution as the reducing system at room temperature and GO paper obtained via vacuum filtration of GO aqueous dispersion as precursor. The effect of immersing time in the system, morphology and structure on the resulting rGO paper were investigated by X-ray diffraction, scanning and transmission electron microscopy, Raman spectroscopy, X-ray photoelectron spectroscopy and capacitive behavior. Results showed that the rGO-60 paper (reduced for 60 min) displayed superior capacitive performance with high specific capacitance (130 F/g) as compared with other rGO papers under various treating times. The reduction time plays a key role in the morphology, structure, reduction degree and capacitive performance.