Optimized Synthesis of Nanostructured Trimetallic Mn–V–Fe Selenides with Battery-Type Behavior for High-Performance Hybrid Supercapacitors

Abstract

The design and synthesis of innovative materials with a specific architecture are necessary to advance the supercapacitor industry. Recently, transition metal selenides have been identified as an auspicious type of material for energy storage devices due to their enormous electronic conductivity and high theoretical capacitance. Consequently, mono- and diselenides have been extensively investigated. Trimetallic selenides, however, are infrequently reported, and their charge storage mechanism is still not fully understood. Herein, earth-abundant trimetallic Mn–V–Fe selenide (MVF-Se) is successfully fabricated via a two-step hydrothermal approach. The chemical composition, structure, and morphology of the as-synthesized material have been thoroughly characterized. The electrochemical tests revealed that the MVF-Se electrode possesses a high areal capacitance of 16,212.88 mF cm–2 at 1 mA cm–2 in the three-electrode configuration. In addition, the assembled asymmetric supercapacitor device by coupling MVF-Se and activated carbon as the positive and negative electrodes, respectively, demonstrates a desirable 0.56 mWh cm–2 energy density at a 1.0 mW cm–2 power density. After 17,000 charge/discharge cycles, the device exhibits robust cyclic stability with a 95% capacitance retention.

NiFe-LDH/MoS2/MXene Nanocomposites as an Electrode Material for Battery-Type Supercapacitors

“…In addition, the contribution percentage for different scan rates is presented in Figure f. It can be observed that the diffusion-controlled contribution gradually decreases as the scan rate is increased, indicating the sluggish ion diffusion …”

Compositionally variant bimetallic Cu–Mn oxysulfide electrodes with meritorious supercapacitive performance and high energy density

“…3(c)), which are ascribed to the metal-oxygen bond (M-O), and adsorbed oxygen containing species (such as H 2 O, O 2 , and CO 2 ), respectively. 2,61 However, the two wellresolved spin peaks in the high resolution XPS spectrum of S 2p (Fig. 3(d)) revealed the presence of oxidized sulfur species adsorbed on the surface in the form of sulfates and hydrogen sulfates through the peak located at 168.8 eV.…”

“…However, they still have lower energy density than rechargeable batteries. [1][2][3] The energy density of supercapacitors can be enhanced via two pathways: expanding the cell working voltage by using asymmetric supercapacitor devices and/or the proper choice of electrode materials. In this regard, nanostructured materials containing mixed metals and anions have been shown to outperform the conventional counterpart materials in terms of electrochemical performance and durability.…”

Environmentally Benign Natural Hydrogel Electrolyte Enables a Wide Operating Potential Window for Energy Storage Devices

“…To keep up with the electronics revolution prevailing in the modern world, the ever increasing demand for energy, and exhaustion of fossil fuels, alternative and green energy storage platforms are essential. , In this regard, electrochemical supercapacitors with exceptional power density, lengthy lifespan, and environmental friendliness, are considered one of the most promising energy storage devices. , However, their practical application is hindered by their lower energy density than batteries. Both electrode and electrolyte materials are crucial for developing high-performance supercapacitors, according to the specific energy equation ( E = 1/2 CV 2 ), where E , C , and V are the specific energy density, the calculated capacitance, and the operating potential window, respectively. , In this context, considerable efforts have been devoted to developing electrode materials with superior specific capacitance.…”