Nanoarchitectonics with electrochemical additive manufacturing process for printing the reduced graphene oxide

Abstract

The synthesis process of reduced graphene oxide (rGO) sheets generally requires the printing of graphene oxide (GO) as a first step and later its reduction through a chemical or thermal route to get the required rGO in the second step. The present work demonstrates the printing of rGO using 0.1% w/v dispersion of GO in water in a single-step process. The method uses the nascent electrochemical additive manufacturing, which allows for non-template-based deposition of microscopically patterned systems. The samples are deposited at 1, 3, and 5 V at 0.1 mm s⁻¹ printing speed. Deposited rGO is characterized using XRD, Raman, and FTIR for various qualitative and quantitative aspects. The surface morphology and topographical studies are performed using SEM and AFM techniques. The RMS roughness calculated using the AFM results, ranging from 5.7 nm to 15.3 nm for 1 to 5 V, indicates the trend of increasing roughness with the deposition potential. The XAS spectroscopy data show that the sample printed at 5 V has the highest purity rGO. The capacitive behaviour of the as-deposited rGO has also been discussed and contrasted with the rGO deposited using other prevalent methods. The specific capacitance of the micro capacitor was found up to 10.84 F g⁻¹ with coulombic efficiencies for 500 cycles at 0.2 A g⁻¹.