Recent Trends in Bimetallic Oxides and Their Composites as Electrode Materials for Supercapacitor Applications

Abstract

There is a growing interest in supercapacitors as energy storage systems due to their high specific power, fast charge/discharge rates, and long cycling stability. Researchers have focused recently on developing nanomaterials to enhance the capacitive performance of supercapacitors. The inclusion of electroactive components, such as transition metal oxides (TMOs), carbonbased materials, and conducting polymers (CPs), is believed to play an important role in improving the electrochemical behavior of the electrode materials. Nevertheless, supercapacitors containing TMOs, carbon-based materials, and CPs commonly suffer from inferior ion-transport kinetics and poor electronic conductivity, which can affect the rate capability and cycling stability of the electrodes. Therefore, the development of TMO/CP and TMO/carbon-based electrode materials has gained widespread attention because they synergistically combine the advantages of both materials, enabling revolutionary applications in the electrochemical field. In general, TMOs have given good performance as electrodes for supercapacitors by further increasing the performance of the electrode when two metal cations are introduced into a single crystal structure. This Review describes and highlights recent progress in the development of bimetallic oxides regarding their design approach, configurations, and electrochemical properties for supercapacitor applications, at the same time providing new opportunities for future energy storage technologies.

MOF-derived hierarchical core–shell hollow Co3S4@NiCo2O4 nanosheet arrays for asymmetric supercapacitors

“…24 In addition, bimetallic oxides have more lattice sites in the crystal structure, so that the material has better stability. 25 Herein, hierarchical core-shell hollow Co 3 S 4 @NiCo 2 O 4 nanosheet arrays are constructed, and used as binder-free electrodes for SCs. The construction process of the electrode consists of three steps (Scheme 1).…”

“…Moreover, the hierarchical coreshell structure provided large accessible surface areas, and NiCo 2 O 4 also had high specific capacitance and stability, and thus all these factors contributed to boosting the electrochemical performance. 24,25 As expected, the Co 3 S 4 @NiCo 2 O 4 / rGO/NF exhibited a largely improved specific capacitance (6.34 F cm −2 /1681 F g −1 at 2 mA cm −2 ), rate performance (57.9% at 50 mA cm −2 ) and cycling durability (70.9%, after 5000 cycles), compared with Co 3 S 4 /rGO/NF (1.55 F cm −2 at 2 mA cm −2 , 36.3% at 50 mA cm −2 , and 43.8%, after 5000 cycles). Meanwhile, the constructed Co 3 S 4 @NiCo 2 O 4 /rGO/NF//AC ASC exhibited a high energy density of 35.7 W h kg −1 at a power density of 799.3 W kg −1 .…”

Polymer Composites with Quantum Dots as Potential Electrode Materials for Supercapacitors Application: A Review

“…Besides that, major drawbacks of batteries are the lack of safety, low flexibility and heavy mass. All these issues can be overcome easily by flexible small compact SCs and also safety major can be taken care by implementing solid-state or semi-solid or gel-polymer electrolyte in SCs [1]. In general, SCs are divided into several categories such as EDLC SCs, pseudo-SCs, faradaic-SCs or hybrid SCs.…”

Development of Binder Free Interconnected 3D Flower of NiZn2O4 as an Advanced Electrode Materials for Supercapacitor Applications

“…With the increasing demand for portable devices, whose function is supported by energystorage electrodes, much attention in research has focused on energy storage in the development of sustainable alternatives that allows for reducing fossil fuel consumption [1][2][3]. For this purpose, efforts have also been focused on developing various innovations for new energy-storage materials and devices, such as batteries and supercapacitors, for numerous important reasons [2][3][4][5][6][7]. Supercapacitors (SCs) have advantages compared to batteries, such as low internal resistance, long life, power density, light weight, and portability.…”