Original Article:
Synthesis and Characterization of Geminal Diazido Derivatives Based on Diethyl Malonate
Muhammad Faisal Iqbal, et al.
Electrochimica Acta, 2018, 273, 136-144.
10.1002/ejic.202100212
Supercapacitors are considered as potential energy storage devices due to their excellent energy density, power density, charge-discharge rate, and cycle life. Various materials have been investigated for supercapacitor applications, but there are many limitations due to their lowest efficiency, complex synthesis, poor electrical conductivity, negligible surface area, and relatively high cost. For example, polymers are expensive and difficult to manufacture, oxides exhibit lower electrical conductivity, carbonaceous materials exhibit non-Faradaic reactions and thus have lower energy densities, etc.
In contrast, metal sulfides have had a significant impact in supercapacitor applications in the last decade due to their simplicity, abundant presence, good electrical conductivity, and abundant redox states. Studies have demonstrated that carbonaceous materials can synergistically enhance the electrochemical properties of metal sulfides for supercapacitors. Furthermore, nanostructured materials are believed to play a key role in achieving high efficiencies for energy storage devices. In this study, the researchers successfully prepared graphene oxide (GO)-based strontium sulfide (SrS) nanorods, and explored their electrochemical properties and applications in supercapacitors.
Synthesis Process of GO-Based Strontium Sulfide Nanorods
1. GO was first prepared by the modified Hummers and Offeman method. The nickel foam (NF) was then treated by repeated immersion sonication and drying in the GO dispersion to obtain a suitable GO film thickness and adhesion on the NF substrate.
2. The pre-deposited GO thin film on the NF substrate was immersed in the Sr(NO3)2.6H2O solution, followed by titrating K2S into it to obtain strontium sulfide precipitation. The NF substrates with pre-deposited GO films were subsequently immersed in this mixture in two different autoclaves for hydrothermal reaction synthesis with NH4OH surfactant solution.
Schematic diagram of the synthesis of GO-based strontium sulfide nanorods
Electrochemical Performance of GO-Based Strontium Sulfide Nanorods
GO-based strontium sulfide nanorods as electrode materials can perform well in symmetric supercapacitor applications, and their reliability is manifested in the following aspects:
- The GO film effectively enhanced the specific surface area and conductivity of strontium sulfide nanorods, exhibiting a high specific capacitance of 1831.14 Fg-1 and a good energy density of 91.54 WhKg-1 at a current density of 3 mAcm-2.
- GO-based strontium sulfide nanorods also exhibited a good power density of 1847.47 Wkg-2 at a current density of 20 mAcm-2 and a good electrode stability of 67% at a scan rate of 20 mVs-1.
- The symmetrical electrode behavior of GO-based strontium sulfide nanorods was also found to be suitable, as it exhibited specific capacitance and energy density of 155.04 Fg-1 and 10.55 WhKg-1 at a current density of 0.5 mAcm-2, respectively.
- GO-based strontium sulfide nanorods also exhibit a good power density of 294.35 WKg-1 at a current density of 3 mAcm-2.
Chemicals Related in the Paper:
| Catalog Number | Product Name | Structure | CAS Number | Price |
|---|---|---|---|---|
| ACM1314961 | Strontium sulfide |  |
1314-96-1 | Price |
