Multifaceted ethylenediamine and hydrothermal assisted optimum reduced GO‐nanosulfur composite as high capacity cathode for lithium‐sulfur batteries

Abstract

A high specific capacity conducting reduced graphene oxide nanosulfur nanocomposite (RGOSNC) cathode is synthesized via deposition of nanosulfur on graphene oxide (GO) through the hydrothermal treatment in the presence of multifaceted ethylenediamine (EDA) for improving the performance of lithium‐sulfur battery (LiSB). The maximum utilization of active material (sulfur) is facilitated by the attachment of nanosulfur to GO via EDA, and further, optimum reduction of GO into conducting, porous and interconnected RGO is performed via hydrothermal treatment in the available solution having residual EDA. Therefore, GO is reduced in highly conducting RGO without the use of any external reducing agent; minimizing the chance of impurity in the synthesized RGOSNC. A three‐dimensional interconnected porous conducting architecture with nitrogen (heteroatom) doping in RGO of RGOSNC with conductivity ∼1.83 S/cm assists easy electron transportation through conducting RGO network and stabilizes intermediate polysulfide to prevent loss of active material during the electrochemical performance. The synthesized RGOSNC cathode material delivers high initial specific capacities 1448 and 1040 mAh/g at 0.1 and 0.5 C, respectively. Prepared LiSB maintains ∼741 mAh/g retention over 100 cycles at 0.5 C with excellent Coulombic efficiency (∼99%).

Ionic Liquids: Applications in Rechargeable Lithium Batteries

“…and thus help us in making the "Fossil free world". Furthermore, in order to maximize the energy and power density, several industries and R&D groups have continuous worked hard on the improvement of electrochemical performance of electrode materials as well as electrolytes for LIBs [1][2][3][4][5]. Due to high power and energy density, good cycle life and bring light weight, lithium-ion batteries are widely used and industrialized in transportation devices as well as hybrid and electric vehicles [6] as shown in Figure 1.…”

Conducting Carbon Rich Graphitic Carbon Nitride Nanosheets with Attached Nano Sulfur Copolymer as High Capacity Cathode for Long‐Lifespan Lithium‐Sulfur Battery

“…The IFFT of the FFT patterns of pristine GCN issues, and we were also unable to observe sulfur nanoparticles in HRTEM images in our prior study. [14,72] However, due to the co-polymerization of sulfur nanoparticles or confinement of amorphous sulfur in that region HRTEM picture (Figure 6l) of sulfur is successfully acquired in this study. Using the IFFT of the FFT diffraction patterns of the specified area of the HRTEM image of C(20)GCN-Scop, the d-spacing (d ~0.38 nm) is computed which is corresponding to the (222) plane of sulfur.…”

“…[53,56] In carbon-rich samples C(5)GCN, C(10)GCN, C(15)GCN, and C(20)GCN, XRD peaks are shifting towards the lower 2 Theta side (towards the characteristic peak of reduced graphene oxide) with increase of carbon content. [14,53,60] This shift in peak is due to the replacement of nitrogen (N) by carbon (C) in aromatic ring structure of GCN. Thus, XRD results confirm that the graphitic nature of carbonrich samples increases with increase in carbon content.…”

“…[5,65] The high surface area provides more active sites and resists collapse of host structure due to the volumetric expansion of sulfur (from sulfur ~2.0 g cm À 3 to Li 2 S ~1.6 g cm À 3 ) arising due to the formation of intermediate polysulfides during the charging/ discharging process. [14] Raman spectra of synthesized GCN, C(5)GCN, C(10)GCN, C(15)GCN, and C(20)GCN is performed for investigation of enhancement of carbon content, its graphitic nature, and defects/disorders are shown in Figure 2(a). In the pristine GCN, a low intense broad peak at ~1364 cm À 1 (Figure 2a) is observed instead of two distinct D and G bands, which indicates lack of sp 2 hybridization (G-band) in it, due to which GCN behaves like poor conductor.…”

Molybdenum-Doped Li/Mn-Rich Layered Transition Metal Oxide Cathode Material Li1.2Mn0.6Ni0.1Co0.1O2 with High Specific Capacity and Improved Cyclic Stability for Rechargeable Li-Batteries

“…During the last couple of decades, the rechargeable Li-ion battery (LIB) technology has emerged as a good alternative because it delivers very high volumetric/gravimetric energy density as compared to other energy storage devices. Lithium, which is the one of the lightest elements (third) of the periodic table, has the lowest reduction potential of ∼3.04 V vs SHE (standard hydrogen electrode) and provides high theoretical specific capacity (∼3860 mAh g –1 ). − LIBs are being mainly used in mobile phones, laptops, computers, electric vehicles (EVs), etc. However, in the rechargeable LIB technology, cathode materials play a significant role in determining a battery’s high energy and power density. − Moreover, for future applications, large-sized devices having high specific capacity and better durability will be required.…”