Producing “Symbiotic” Reduced Graphene Oxide/Mn₃O₄ Nanocomposites Directly from Converting Graphite for High-Performance Supercapacitor Electrodes

Abstract

Almost all existing methods for preparing reduced graphene oxide/Mn 3 O 4 (RGO/Mn 3 O 4 ) composites are based on the synthetized graphene or graphene oxides (GO), which make them complicated and high-cost processes. Here, we reported a new method, which is able to convert graphite directly to RGO/Mn 3 O 4 composites. Thus, it is simpler, more economical, and productive. The structure of RGO/Mn 3 O 4 inheriting intermediate product GO/MnO 2 composites that are formed by the present method is a novel three-dimensional “multilayer steamed bread” nanostructure, which constitutes mutually beneficial “symbiosis”. The nano-Mn 3 O 4 supports the space between RGO layers and further to the combination of RGO to self-assemble into large-sized (>40 μm) nanocomposites. Meanwhile, the formed Mn 3 O 4 particles were small (60 × 10 nm 2 ) in diameter and distributed homogeneously without the use of any template and surfactant. Because the structure and nanosize of composite cause the excellent electrochemical properties, RGO/Mn 3 O 4 electrodes deliver an enhanced specific capacitance of 438.7 F/g at 0.3 A/g and outstanding cyclic stability (77.5% of its initial capacitance is retained after 1000 cycles).

Preparation of Graphene Oxide/La2Ti2O7 Composites with Enhanced Electrochemical Performances for Supercapacitors

“…In addition, the electrochemical properties of the GO/LTO composite were compared with some recent works concerning graphene (shown in Table ). ,,,− The content ratio of the GO/LTO composite was significantly lower than the previous electrode active materials. However, the GO/LTO composite delivered an excellent specific capacitance among these different composites.…”

One-Pot In Situ Synthesis of Mn3O4/N-rGO Nanohybrids for the Fabrication of High Cell Voltage Aqueous Symmetric Supercapacitors: An Analysis of Redox Activity of Mn3O4toward Stabilizing the High Potential Window in Salt-in-Water and Water-in-Salt Electrolytes

“…As regard to the synthesis of Mn 3 O 4 /rGO-based nanohybrids, previous reports have largely employed multistep synthetic processes, or nonaqueous solvents, ,, and/or a hydrothermal approach, , followed by calcination at a higher temperature, which would be uneconomical and environmentally unfriendly in terms of commercial production. Lately, the synthesis of Mn 3 O 4 -anchored N-doped reduced graphene oxide (Mn 3 O 4 /N-rGO) nanocomposites has been reported.…”

Nanostructured Graphene Oxide-Based Hybrids as Anodes for Lithium-Ion Batteries

“…Mn 3 O 4 /rGO composites have been synthesized using combined techniques such as co-precipitation and subsequent flame procedure [256][257][258], hydrothermal method [259,260], in situ reduction by hydrazine vapour [261], sonication with subsequent heat treatment [262], gel formation and electrochemical reduction process [263], one-step reduction in aqueous phase [264,265], successive ionic layer adsorption and reaction (SILAR) method [222], flame plasma [256], and sonochemistry-assisted method [266,267]. Gund [268].…”