Graphene/ β‐ MnO ₂ composites—synthesis and its electroanalytical properties study in the Mg storage battery

Abstract

Graphene/β-MnO 2 composites were synthesized via ultrasonication method, followed by calcination at 400 C for 4 hours. The structural properties of synthesized graphene and graphene/β-MnO 2 composites were systematically studied using different instruments, such as XRD, FESEM, TEM, EDX, XPS and FT-IR spectroscopy. Furthermore, magnesium storage performance was scientifically studied using various electroanalytical characterizations like galvanostatic charge/discharge, electrochemical impedance spectra and cyclic voltammetry. The GNS/β-MnO 2-20% composite displays the discharge capacity of 110 mAh/g within 60 cycles at a current density of 25 mA/g, which is an excellent rate capability, and magnesium storage performance around 100 cycles. There is a significant improvement in electrochemical properties of GNS/β-MnO 2-20% composite materials as cathode for magnesium storage system due to the synergetic interaction between a pure β-MnO 2 particle and graphene sheet.

Structural and electronic properties of Cs‐adsorbed GaN monolayer and bilayer based on first principles

“…Charge transfer is an important aspect of the adsorption system. 19 Figure 3 shows the schematic diagram of charge transfer between Cs atom and GaN monolayer when Cs is absorbed at different adsorption sites. The figure of charge density difference is also given to observe Mulliken charge distribution.…”

“…PETE device is based on thermionic emission of photoexcited electrons from a semiconductor cathode at high temperature 10 . With the maturity and perfection of nanomaterials and nanotechnology, two‐dimensional (2D) semiconductor materials, represented by graphene, 11‐13 MoS 2 , 14,15 hBN, 16 and so on, gain much attention due to their novel properties and potential applications 17‐19 . These studies show that the physical properties of the atomic‐scale thickness limitation can give 2D semiconductors fascinating electric, mechanic, and thermal properties.…”

“…10 With the maturity and perfection of nanomaterials and nanotechnology, twodimensional (2D) semiconductor materials, represented by graphene, [11][12][13] MoS 2 , 14,15 hBN, 16 and so on, gain much attention due to their novel properties and potential applications. [17][18][19] These studies show that the physical properties of the atomic-scale thickness limitation can give 2D semiconductors fascinating electric, mechanic, and thermal properties. Researchers have also done a lot of theoretical investigation on the structure, electric, optical, and magnetic properties of two-dimensional GaN.…”

OH radical-initiated single-electron transfer for accelerated degradation via carbocation intermediates

“…S9 † ). 30 Therefore, the MnO 2 catalyst would facilitate the generation of ˙OH for efficient degradation.…”

Manganese–carbon (Mn–C) interaction to host Al3+-ions in a β-MnO2–MWCNT composite cathode in rechargeable aluminium ion batteries

“…[32][33][34] It is also observed that non-graphitic pure MWCNTs with EMIM-Cl (1-ethyl-3-methyl imidazolium chloride) ionic liquid electrolyte showed an electrochemical performance with a specific capacity of 64 to 58 mA h g À1 at 99% coulombic efficiency. 35 Recently, we developed a graphene/b-MnO 2 composite system for magnesium batteries, which further inspired us to explore it for AIBs. 36 Manganese dioxide (MnO 2 ) is the foremost cathode material in battery technology because of various benefits, like being abundantly available in the earth's crust, low cost, environmental friendliness, and low toxicity.…”