Application of flammulina-velutipes-like CeO2/Co3O4/rGO in high-performance asymmetric supercapacitors

Electrochemical synthesis and supercapacitor performance of manganese and cerium oxide-doped polyaniline composites

In this study, polyaniline-based conductive polymers doped with manganese oxide and cerium oxide were electrochemically synthesized for the first time. Unlike previous studies, manganese oxide and cerium oxide doped polyaniline synthesis was carried out in perchloric acid. The resulting composite materials were characterized using spectroscopic and microscopic techniques. The doped polyaniline composites were employed as electrode components in supercapacitors and analyzed using cyclic voltammetry and electrochemical impedance spectroscopy. Changes in capacitive behavior over cycling were examined via galvanostatic charge-discharge measurements. The areal capacitance of the cerium oxide and manganese oxide doped polyaniline electrodes, synthesized under optimal conditions, were measured as 950 mF cm-2and 660 mF cm-2, respectively, at a charge-discharge current of 10 mA cm-2.

Review on recent advancements in the role of electrolytes and electrode materials on supercapacitor performances

Supercapacitors currently hold a prominent position in energy storage systems due to their exceptionally high power density, although they fall behind batteries and fuel cells in terms of energy density. This paper examines contemporary approaches aimed at enhancing the energy density of supercapacitors by adopting hybrid configurations, alongside considerations of their power density, rate capability, and cycle stability. Given that electrodes play a pivotal role in supercapacitor cells, this review focuses on the design of hybrid electrode structures with elevated specific capacitance, shedding light on the underlying mechanisms. Factors such as available surface area, porosity, and conductivity of the constituent materials significantly influence electrode performance, prompting the adoption of strategies such as nanostructuring. Additionally, the paper delves into the impact of novel bio-based hybrid electrolytes, drawing upon literature data to outline the fabrication of various hybrid electrode materials incorporating conducting polymers like polyaniline and polypyrrole, as well as metal oxides, carbon compounds, and hybrid electrolytes such as ionic liquids, gel polymers, aqueous, and solid polymer electrolytes. The discussion explores the contributions of different components and methodologies to overall capacitance, with a primary emphasis on the mechanisms of energy storage through non-faradic electrical double-layer capacitance and faradaic pseudo-capacitance. Furthermore, the paper addresses the electrochemical performance of hybrid components, examining their concentrations and functioning via diverse charge storage techniques.

Synthesis of nickel-doped ceria nanospheres for in situ profiling of Warfarin sodium in biological media

Venous thromboembolism is one of the major disorders, which is significantly increased the mortality and morbidity rate. Warfarin sodium (WFS) is the most extensively prescribed drug for the prevention of thromboembolic diseases however, it has a narrow therapeutic index. Recently, many methods for detecting and monitoring the level of WFS have been proposed. However, the electrochemical method has gained more interest than the other traditional method due to its ease of operation. This article describes the hydrothermal synthesis of nickel-doped cerium oxide (CeO2@Ni) nanospheres for the selective electrochemical determination of WFS. Various spectroscopic techniques have been used to analyze the chemical composition, and surface morphology of CeO2@Ni nanospheres. Further, the prepared CeO2@Ni nanospheres modified electrode demonstrated excellent electrocatalytic behavior for WFS detection, with an ultralow detection limit of 6.3 × 10-9 M, a linear range of 1.0 × 10-8 M to 1.51 × 10-4 M and 1.51 × 10-4 M to 9.51 × 10-4 M, and a higher sensitivity of 2.9986 µA µM-1 cm2. Therefore, we believe that the CeO2@Ni nanosphere electrocatalyst can serve as a potential electrode catalyst for the sensing of WFS in real-time applications.

Rare Earth-Based Nanomaterials for Supercapacitors: Preparation, Structure Engineering and Application

Supercapacitors (SCs) can effectively alleviate problems such as energy shortage and serious greenhouse effect. The properties of electrode materials directly affect the performance of SCs. Rare earth (RE) is known as "modern industrial vitamins", and their functional materials have been listed as key strategic materials. In the past few years, the number of scientific reports on RE-based nanomaterials for SCs has increased rapidly, confirming that adding RE elements or compounds to the host electrode materials with various nanostructured morphologies can greatly enhance their electrochemical performance. Although RE-based nanomaterials have made rapid progress in SCs, there are very few works providing a comprehensive survey of this field. In view of this, a comprehensive overview of RE-based nanomaterials for SCs is provided here, including the preparation methods, nanostructure engineering, compounds, and composites, along with their capacitance performances. The structure-activity relationships are discussed and highlighted. Meanwhile, the future challenges and perspectives are also pointed out. This Review can not only provide guidance for the further development of SCs but also arouse great interest in RE-based nanomaterials in other research fields such as electrocatalysis, photovoltaic cells, and lithium batteries.

Preparation and application of a flower-rod-like Bi2S3/Co3O4/rGO/nickel foam supercapacitor electrode

Herein, we have prepared a new nanocomposite Bi2S3/Co3O4/rGO/Ni foam substrate electrode through hydrothermal synthesis and an annealing process.

Fabrication of an ultra-stable composite electrode material of La2O3/Co3O4/graphene on nickel foam for high-performance supercapacitors

A three-dimensional lily-like structure was constructed by the novel combination of La2O3, Co3O4, and graphene on nickel foam (LCGN) through hydrothermal synthesis and thermal annealing.

Transition Metal Oxide Electrode Materials for Supercapacitors: A Review of Recent Developments

In the past decades, the energy consumption of nonrenewable fossil fuels has been increasing, which severely threatens human life. Thus, it is very urgent to develop renewable and reliable energy storage devices with features of environmental harmlessness and low cost. High power density, excellent cycle stability, and a fast charge/discharge process make supercapacitors a promising energy device. However, the energy density of supercapacitors is still less than that of ordinary batteries. As is known to all, the electrochemical performance of supercapacitors is largely dependent on electrode materials. In this review, we firstly introduced six typical transition metal oxides (TMOs) for supercapacitor electrodes, including RuO₂, Co₃O₄, MnO₂, ZnO, XCo₂O₄ (X = Mn, Cu, Ni), and AMoO₄ (A = Co, Mn, Ni, Zn). Secondly, the problems of these TMOs in practical application are presented and the corresponding feasible solutions are clarified. Then, we summarize the latest developments of the six TMOs for supercapacitor electrodes. Finally, we discuss the developing trend of supercapacitors and give some recommendations for the future of supercapacitors.