Preparation of nitrogen and sulphur Co-doped reduced graphene oxide (rGO-NS) using N and S heteroatom of thiourea

Abstract

Graphene oxide (GO) has been synthesized via modified Hummer's method with graphite powder as a starting material. The synthesized reduced graphene oxide (rGO) was prepared by GO as a precursor. Synthesis of rGO-NS was performed by hydrothermal method using a dopant thiourea as nitrogen (N) and sulphur (S) donors with the ratio of GO: thiourea = 1:10, 1:15, and 1:20 (w/w), respectively. Characterization using Fourier Transform Infra-Red (FTIR) spectroscopy shows several peaks that have an agreement with −OH, C=O, C=C, C-OH, and C-O functional groups for GO and absorption peaks of −OH, C=C, and CO functional groups for rGO with different intensity, while modified materials of variation rGO-NS emerged typical absorptions of −OH, C=C, C=N, C-N, and C-S functional groups. GO and rGO material that have been analysed using X-Ray Diffraction (XRD) shows a dominant peak at 2θ 10.77° (001) and 24.97° (002), respectively. While the distance between layers (d Spacing ) on rGO (3,56 Å) was lower than GO (8,22 Å). Compared to rGO, XRD analysis also shows that the addition of N and S on GO structure caused shifting of 2θ in 23,73°-24,06° (002) and calculated d spacing of rGO-NS is found to be 3,70 Å−3,74 Å. Morphological observation of rGO-NS using Scanning Electron Microscopy (SEM) shows that rGO-NS is a thin transparent sheets formed because the exfoliation process of GO material.