3D nitrogen-doped graphene created by the secondary intercalation of ethanol with enhanced specific capacity

Abstract

Here, we report an improved synthesis strategy for 3D nitrogen-doped graphene to increase the specific capacity of supercapacitors. Ethanol replaces the strong oxidant hydrogen peroxide in the improved Hummers method, and the loose porous structure is conducive to charge transfer. N-doped porous 3D graphene was synthesized from RGO-C prepared by ethanol secondary intercalation modification of functional groups. Ammonia was selected as the dopant; the microstructure and electrochemical performance of samples synthesized at different temperatures were examined. The results demonstrate that the 3D nitrogen-doped graphene (N-RGO-5) had a layered tuple shape with a sheet thickness of 0.612 nm.The specific surface area of the 3D N-RGO-5, which was prepared at 190°C, was 258.371 m2 g−1, which was higher than that (5.877 m2 g−1) of the original graphite. The 3D N-RGO-5 exhibited a specific capacitance of 236 F g−1 and an energy density of 32.78 Wh kg−1 at a current density of 1 A g−1, which is 27% higher than the specific capacitance of RGO. The 3D N-RGO-5 demonstrated an excellent capacity retention rate of 93.6% after 5000 cycles at a current density of 1 A g−1. This study demonstrates that the unique 3D structure and N-doping of N-RGO considerably improved the overall energy storage performance of graphene-based nanomaterials.

Graphene/Heterojunction Composite Prepared by Carbon Thermal Reduction as a Sulfur Host for Lithium-Sulfur Batteries

“…A total of 12 g of potassium permanganate was added to it and the temperature was increased to 50 °C (40 min), 60 °C (7 h), 90 °C (30 min), and finally, 30 mL of H 2 O 2 was added to it to obtain a bright yellow graphene oxide solution. After being cooled, the graphene oxide was left to separate, centrifuged to a pH of 7, and finally freeze-dried, as previously reported by our subject group [ 32 , 33 ].…”

A Review of High-Energy Density Lithium-Air Battery Technology: Investigating the Effect of Oxides and Nanocatalysts

“…Increased defects increase the storage capacity of lithium ions. For example, milling operations on carbon nanotubes increase the density of defects, reduce the length of carbon nanotubes, and can affect the performance of the electrode [14,[220][221][222][223][224], and high irreversible capacity due to SEI layer formation and other side effects suffers severely [15,225,226]. erefore, chemical etching and milling methods are suggested to eliminate these defects.…”

Reduced zwitterionic graphene oxide sheets decorated with nickel nanoparticles as magnetically and efficient catalyst for A3‐coupling reactions under optimized green experimental conditions

“…[39] Among them, graphene oxide (GO) sheets are widely used in various applications because they offer unique physicalchemical properties due to the presence of hydroxyl, carboxyl, and epoxy functional groups onto their surface, thus making its processing and functionalization more suitable. [40][41][42][43][44][45][46] Therefore, recently functionalized GObased materials were used as substrates for the adsorption of metal ions from aqueous solutions and supported catalysis. [47][48][49][50][51] For example, Chaabane et al [49] modified GO sheets with N,N-bis(2-pyridylmethyl)ethylenediamine (BPED) and then by 1,3-propanesultone (PS) to yield a zwitterionic GO adsorbent that was highly efficient for removing Co(II) and Ni(II) ions from aqueous solutions.…”