GeO 2, PSS (analytically pure), and graphite powders (spectral pure) were purchased from Sinopharm Chemical Reagent Beijing Co. The study provided a strategy to synthetize RGO-GeNPs which could be served as promising anode materials for LIBs.Īll reagents in this work were of analytical grade and were used as received without further purification. Poly(sodium 4-styrenesulfonate) (PSS) was employed to obtain aqueous dispersibility of PSS-RGO-GeNPs, which was hopeful to further improve its electrochemical properties. Stable aqueous dispersions of nanocomposites were synthesized by the reduction of exfoliated graphite oxide and GeO 2 precursor. Herein, we demonstrate a simple and mild method to fabricate the RGO-GeNPs in aqueous solution. Therefore, it was important to find a new synthesized method to prepare water-dispersable Ge nanocomposites with excellent electrical properties. Moreover, the loss of stability and electrochemical properties often inevitably occurred due to irreversible agglomeration and poor dispersions of graphene-Ge nanocomposites in aqueous solution. However, the strategy did not provide a facile route for synthesis. reported the synthesis of graphene-Ge nanocomposite by chemical vapor deposition (CVD), which exhibited a good capacity retention behavior and long cycle life as anode materials.
Although the nanocomposites exhibited a high specific capacity as anode materials for lithium ion batteries (LIBs), this strategy did not acquire a material with long cycle life. For instance, Cheng and Du reported the synthesis of graphene-Ge nanocomposites from expensive GeCl 4 and graphene oxide as precursor. Recently, some works have reported about synthetizing and studying the electrochemical performance of graphene mixed with Ge nanomaterials. Recently, graphene has been used as an excellent substance to acquire variously functional nanomaterials, including graphene-silver nanoparticles, graphene-gold nanoparticles, graphene-TiO 2 nanomaterials, and graphene-palladium nanoparticles. Graphene is a single-atom-thick two-dimensional graphitic carbon material, which possesses extraordinary large surface area and chemical stability. Moreover, organic and inorganic substances such as PVP, (CH 3) 3SiCl, amino acid, and graphene have been employed to stabilize Ge nanomaterials and to develop nanomaterials with variant morphologies these strategies could partly improved the physical performance and stability of the Ge nanomaterials. Though Ge nanomaterials have excited an attractive prospect, the majority of synthetic strategies did not provide facile aqueous solution routes. Furthermore, the application of Ge nanomaterials was often hampered by the aggregation and lowered physical properties, as these facts directly determine the applications of Ge nanomaterials. Nevertheless, synthesis and application of Ge nanomaterials have suffered from serious limitations such as some stiff experimental conditions, high temperatures, toxic precursors, and complex synthesis process. In recent years, a variety of strategies have been developed to synthesize functional GeNPs physically and chemically. Ge or Ge-based nanomaterials have shown valuable physical properties for various applications in solar cells, optoelectronics, bio-imaging, energy conversion, and storage. The group IV semiconductors such as silicon (Si) and germanium (Ge) were unique materials with a wide range of technological applications. With the advent of nanoscience and nanotechnology, semiconductor nanomaterials have received much attention due to their unique physical properties and potential applications in electronics, catalysts, sensors, and optical devices. This study showed a facile strategy to synthetize graphene and Ge nanocomposites which can be a hopeful anode material with excellent electrical properties for lithium ion batteries. The resulting nanocomposites exhibited high specific capacity and good cycling stability after 80 cycles. The as-synthesized RGO-GeNPs showed excellent battery performance when used as an anode material for Li ion batteries. A possible mechanism to interpret the formation of RGO-GeNPs was proposed.
.jpg "malvern zetasizer graphene analyses")
Stable aqueous dispersibility of RGO-GeNPs was further improved by poly(sodium 4-styrenesulfonate) (PSS) to obtain amphiphilic polymer-coated RGO-GeNPs (PSS-RGO-GeNPs). The information about morphology and chemical composition of the nanomaterials were obtained by TEM, FTIR, EDS, and XRD measurements. Aqueous solution synthesis of reduced graphene oxide-germanium nanoparticles (RGO-GeNPs) was developed using graphene oxide (GO) as stabilizer, which could be conducive to obtain better excellent electrical properties.
0 kommentar(er)
