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In this study, we have synthesized facile Cu‐based CuO:Er2O3 nanoelectrode material for energy storage and generation. CuO:Er2O3 nanomaterial was synthesized employing phyto‐extract of Amaranthus viridis L. (AVL) as stabilizing and reducing agents. Spherical‐shaped CuO:Er2O3 nanomaterial was initially employed to study supercapacitor behavior. The specific capacitance of 82.25 F/g was found at 0.5 A/g by galvanostatic charge–discharge, whereas the value of 319 F/g was achieved at 2 mV/s by cyclic voltammetry (CV) measurements. Furthermore, CuO:Er2O3 electrode was investigated for water splitting energy generation potential and revealed an overpotential value of 323 mV at 10 mA/cm2 for hydrogen evolution reaction (HER). However, for the oxygen evolution reaction (OER), an overpotential value of 370 mV was found. The electrochemical impedance analysis revealed the faster flow of electrons and ions, suggesting great conductivity and lower resistance of the fabricated electrode. Thus, current electrochemical results are proposing CuO:Er2O3 as an competent electrode for overall energy‐generating as well as storage applications. [ABSTRACT FROM AUTHOR]

Using single‐source precursor route, this work reports the synthesis of the novel chalcogenide heterosystem, i.e., BaS:CoS:La2S3 trichalcogenide heterosystem. With the narrowed band gap energy, BaS:CoS:La2S3 expresses excellent photonic response with 3.47 eV of tailored band gap resulting from chemical synergism. This chalcogenide is marked by superior crystallinity and possessed an average crystallite size of 18.29 nm. Morphologically, BaS:CoS:La2S3 exists in the form of the roughly spherical grains arranged in the irregular manner. The developed chalcogenide is assessed for charge storage by fabricating the electrode using a nickel form as a support. In a 0.1 m KOH background electrolyte, the BaS:CoS:La2S3 adorns electrode excelled in achieving a specific capacitance of 967.24 F g−1. In addition, this trichalcogenide expresses the specific power density of 1659 W kg−1. Fabricated electrode retains original capacitance after different cycles. Regarding electrode–electrolyte interactions, the fabricated electrode shows minimal resistance, with an equivalent series resistance (Rs) of 1.42 Ω as indicated by impedance studies. Additional circuit elements, including CPE (Yo = 2.17 × 10−04, n = 0.71) and Rct (6.97 Ω cm−2), are obtained after circuit fitting for the BaS:CoS:La2S3 trichalcogenide decorated electrode. Exhibiting stable behavior for 43 h, the synthesized material demonstrates profound durability and functionality. [ABSTRACT FROM AUTHOR]

Electrodeposition, a binder-free technique, enables the formation of uniform and well-defined structures on the electrode surface. Herein, the material has directly grown on nickel foam by deposition through cyclic voltammetry at a fixed scan rate. The surface morphology of as-synthesized electrodes is observed with SEM and the electrochemical examination has been performed in three-electrode assembly. The highest specific capacitance attained from GCD analysis for MnS is 1453 F/g, CoS has 2476 F/g and CuS exhibits 1908 F/g at 6 A/g current density. The quantitative investigation of the inherent charge storage mechanism of an individual electrode is achieved by implementing different mathematical models on experimental data sets. The electrodes displayed a more diffusive contribution which uncovered our findings that each electrode illustrates the battery-grade properties. The results suggested that the fabricated electrode consumes an excellent potential as a high energy source for hybrid energy storage devices. [ABSTRACT FROM AUTHOR]

A shift to alternate energy sources is needed at the present time to address rising environmental concerns. The current research work aims to use a chemical‐free and green route to synthesize nanocomposite for their application as an electrode in the generation as well as storage of energy. Subsequently, the green synthesis of Bi2O3‐Sb2O3 nanocomposite was carried out using the leaf extract of Amaranthus viridis. The synthesized nanocomposite revealed a well‐arranged pattern of spherical nanoparticles with a crystal size of 29.43 nm and a band gap value of 2.5 eV. The hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) potentials of Bi2O3‐Sb2O3 were studied through linear sweep voltammetry (LSV) and electrochemical impedance spectroscopy (EIS), whereas the energy storage studies were performed using cyclic voltammetry (CV) and galvanostatic charge discharge (GCD) techniques. The synthesized nanomaterial showed promising results for HER with an overpotential value of 205 mV as compared with OER, where an overpotential value of 450 mV was observed. However, excellent cyclic stability was witnessed for both reactions up to 1000 cycles. CV studies revealed an outstanding capacitance value of 348 F/g at a scan rate of 2 mV/s, whereas a specific capacitance of 269.5 F/g at a current density of 0.5 A/g was observed using GCD. The 15 h of electrode stability further endorsed the potential of synthesized material for energy‐based applications. [ABSTRACT FROM AUTHOR]

Background: Researchers are keen to reduce the over potential value through fabrication of electrocatalyst consisted of environmentally benign and inexpensive material. Supercapacitors on the other hand have gained immense attention in recent years as an energy storage device due to the high power density potential of these devices as compared to conventional batteries based storage system. Aim: The research aims to synthesize nanoscale transition metal oxides (TMO) through green route. TMO based nanomaterials have vast role in energy related applications. Materials & methods: In this study, organic compounds of A. Viridis were used as reducing and stabilizing agents in the synthesis of binary nanocomposite Sb2O3-ZrO2. The synthesized nanocomposite was characterized using xray diffraction, Fourier transform infrared spectroscopy, ultraviolet-visible spectroscopy, field emission scanning electron microscopy and energy dispersive spectroscopy. The electrode material was analyzed for supercapacitor potential using cyclic voltammetry and galvanostatic charge discharge techniques. HER and OER studies were also conducted using electrochemical impedance spectroscopy and linear sweep voltammetry. The synthesized material was also tested for stability. Results & discussion: The crystal size was 15.9 nm. Optical band gap of 2.55 eV was obtained through Tauc plot. The capacitance value of 339.8 F/g at 2 mV/s and the specific capacitance of 100.6 F/g was obtained at 1 A/g. The overpotential value of 201 mV and Tafel value of 121 mV/dec was recorded for the HER, whereas the lower Tafel value of 106 mV/dec and over potential value of 383 mV was determined for OER. Electrode showed promising stability up to various cycles in case of both applications. Conclusion: The obtained results revealed the promising performance with excellent stability of fabricated electrode for super capacitor as well as water splitting studies. [ABSTRACT FROM AUTHOR]

Conducting polymers have attained a lot of interest due to extraordinary conductivity, large pore size, and surprising stability. In this work, the conducting polymer polyaniline (PANI) and niobium sulfide (NbS) were synthesized by polymerization of aniline and hydrothermal method, respectively. The PANI@NbS nanocomposite electrode material had a specific capacity (Cs) of 1050 C g−1, which is larger than that of the reference sample (NbS = 300 C g−1). Besides, the hybrid device (PANI@NbS//PANI@AC) was designed and the electrochemical characteristics were determined. The hybrid device showed an excellent value of Cs of 1207 C g−1 with higher energy density Ed and power density Pd. The device also exhibited remarkable stability, and 85 % of the initial capacity is retained after 1000 cycles. [ABSTRACT FROM AUTHOR]

Carbon nanotubes (CNTs) have attained great interest from researchers due to their excellent electrical conductivity, vast surface area, and good chemical stability. In this work, the sulphide‐based composite Ag2S@ZnS was synthesized using the hydrothermal method and was doped with CNTs in various weight percentage ratios. The structural and morphological characteristics of the samples were evaluated by employing X‐ray diffractometry (XRD), X‐ray photo spectroscopy (XPS), scanning electron microscopy (SEM), Brunauer–Emmett–Teller (BET) analysis, and thermogravimetric analysis (TGA), while cyclic voltammetry (CV) and galvanostatic charge/discharge (GCD) were also executed for their electrochemical characterization. The performance of the Ag2S@ZnS electrode was enhanced after the doping of CNTs because of their synergistic effect. An extraordinary specific capacity (Qs) of 946.5 Cg−1 (262.91 mAh g−1) was exhibited by Ag2S@ZnS with 50% CNTs doping (Ag2S@ZnS/CNT‐50%), which is significantly greater than the reference samples. Furthermore, an asymmetric supercapacitor was designed and assessed for its electrochemical properties. The specific capacity of the asymmetric supercapacitor reached 148.62 Cg−1 (41.28 mAh g−1). The device showed improved stability and retained the 87% initial capacity after 5000 cycles. The energy and power densities were found to be 33.02 Wh kg−1 at 639.98 W kg−1, respectively, with a high value of coulombic efficiency of 92%. The device succeeded in acquiring a higher power density of 3200 W kg−1 for an energy density of 4 Wh kg−1. These astonishing results provide opportunities to design high‐performance electrode materials for extraordinary energy storage devices. [ABSTRACT FROM AUTHOR]

Hybrid supercapacitors are energy storage technology offering higher power and energy density as compared to capacitors and batteries. Cobalt-doped manganese oxide (Co@MnO2) was synthesized using an easy and affordable sol–gel process and measured the electrochemical properties. A value of the specific capacity of 1141.42 Cg−1 was obtained which was larger in comparison to the reference sample (MnO2 = 673.79 Cg−1). The value of the specific capacitance was achieved 1902 Fg−1. To design a hybrid supercapacitor device, Co@MnO2 was used as the positive electrode and the activated carbon was employed as the negative electrode in two-electrode assembly. According to calculations, the measured value of the specific capacitance of Co@MnO2 was 713.25 Fg−1. The charge storage mechanism is supported with the help of Randles–Ševčík and Dunn's models. The estimated value of energy and power densities were 3200 Wh kg−1 and 24 Wkg−1, respectively. The stability of this device was checked by putting it to 1000 charging and discharging cycles, and it retained 86% of its initial capacity. Our result provides a platform for enhancing the functionality of energy storage systems. [ABSTRACT FROM AUTHOR]

Energy storage devices have attained a lot of interest because of the large demand for energy in the present era. Carbon nanotubes have attained huge interest in energy applications because of their extraordinary conductivity, sensitivity, and storage capability. In this work, the zinc niobium sulfide (ZnNbS) is synthesized using the hydrothermal method. A remarkable value of the specific capacity (Cs) of 1054.21 Cg−1 is obtained, which is comparatively better than the reference sample. Besides, the CNTs-doped ZnNbS and activated carbon (ZnNbS/CNT//AC) are utilised to design the hybrid supercapacitor. The hybrid device showed a high value of Cs of 196.1 Cg−1 at 2 Ag−1. Further, the hybrid supercapacitor exhibited an improved value of energy density (39.4 WhKg−1) and power density (2400 WKg−1), which is much improved compared to the previously reported values. To check the stability of the device, it is measured up to 5000 charging/discharging cycles. The device showed 95% of capacity retention. Our findings provide a new platform for designing high-performance supercapattery-type energy storage devices. The doping of CNT in sulfide-based materials opens new possibilities to design high performance energy storage devices. [ABSTRACT FROM AUTHOR]

Supercapacitors have proven themselves as a subject of interest over the years for energy storage. As a result, it is not surprising that significant effort has been put into supercapacitor research. However, a device with all desirable properties still needs to be developed, requiring special attention. A simple synthesis of porous magnesium niobium silver phosphate (Mg3Nb1−xAgx(PO4)3) nanocomposites is presented using a novel mixed solvent solution and a hydrothermal method. The MgNbAgPO4 anode with an interconnected porous structure not only offers a large number of active sites for divalent ion trapping but also improves charge transfer kinetics. As a result, the Mg3Nb1−xAgx(PO4)3 anode has a high specific capacity of 958 C g−1 using a binder‐free electrode and better rate capability. The full‐cell design is also built with Mg3Nb1−xAgx(PO4)3 and activated carbon (AC). The hierarchical pore structure and appropriate functional groups Mg3Nb1−xAgx(PO4)3 anode deliver a maximum energy density of 57 Wh kg−1, a high power density of 1200 kW kg−1, and anti‐self‐discharge solid behavior. The analysis of the charge storage mechanism suggests that Mg3Nb1−xAgx(PO4)3//AC supercapattery involves adsorption/desorption and Faradic reactions to store charge. This study opens the path for high‐performance Mg3Nb1−xAgx(PO4)3 electrode and gives a better knowledge of charge storage. [ABSTRACT FROM AUTHOR]

Hybrid supercapacitor or supercapattery devices have gained significant attention for their impressive power (Pd) and energy densities (Ed), as well as their exceptional cyclic stability compared to traditional storage devices. In this study, manganese niobium sulfide (MnNbS) is synthesized using a hydrothermal method. To enhance the electrochemical performance of MnNbS, polyaniline (PANI) is blended at varying mass ratios. Initially, the electrochemical properties of MnNbS/PANI are evaluated using a three‐electrode configuration, consisting of working, counter, and reference electrodes. At a current density of 2 A g−1, MnNbS/PANI exhibits an improved specific capacity ((Cs)$\left(\right. C_{s} \left.\right)$) of 1366 C g−1. Subsequently, to develop a supercapattery energy storage device, a two‐electrode system is constructed. This setup offers enhanced performance and flexibility, making it an ideal choice for high‐performance supercapacitors. Activated carbon (AC) and MnNbS/PANI are employed as the negative and positive electrodes, respectively, in the two‐electrode system. Notably, the device demonstrates outstanding energy density (Ed) of 26.2 Wh kg−1, power density (Pd) of 2072 W kg−1, and specific capacity of 118 C g−1. Furthermore, durability tests involving 1000 charge–discharge cycles reveal a capacity retention of 79%. This study suggests that MnNbS/PANI (at a weight ratio of 80/20%) holds promise as an electrode material for supercapattery applications. [ABSTRACT FROM AUTHOR]

The constant changes in the load power lead permanently to a power mismatch between the power generation and the power consumption. So, the system frequency due to the power imbalance deviates from the nominal value. Consequently, a control loop should be implemented to stabilize the system frequency whenever a load change occurs. This paper presents a new super‐twisting sliding mode control methodology for obtaining an optimal frequency performance in a multi‐pool system. The paper presents a three‐pool system for frequency deviation problems using an optimal gain Super Twisting Sliding Mode Controller (STSMC), which regulates the frequency change and the line power change to zero in a minimal time. The extent of the excellence of the study proposed is evaluated by comparing it with three Benchmark classical controllers, which are the Tilt‐Integral‐Derivative (TID), Proportional‐Integral‐Derivative (PID), and Fractional‐Order PID (FOPID). The parameters of the four controllers are determined by a proposed physical meta‐heuristic optimization technique called Transient Search Optimizer (TSO), inspired by the dynamic behaviour in the electrical circuits comprising storage elements such as capacitors and inductors during the switching actions. The system simulation is performed, and the STSMC proved overwhelming superiority over other controllers, as it deals better with the transient interval of the system response. Renewable Energy sources (RESs) like photovoltaic and wind energy systems are established, and the STSMC is tested with industrial and residential load models. Finally, energy storage devices such as batteries and superconducting magnetic energy storage are implemented to suppress the rapid fluctuations in the system response, and it succeeded in doing that as the system oscillations are greatly damped with the energy storage devices. [ABSTRACT FROM AUTHOR]

PV systems are frequently used in a stand-alone configuration. In a solar PV-based energy-producing system, power fluctuation is a natural occurrence. Alternative sources of energy, including such hybrid grid-tied or energy storage systems, could be discovered when solar PV systems run off-grid to satisfy regional power demands for reliable power supply. This research uses an unusual PV system that can function in both grid-connected and stand-alone states to propose an efficient approach for the power generation challenge in the residential segment. A block of storage battery with sufficient dimensions is included in the system to make sure the constant power supply of such a residential building with an average electricity demand of 10 kWh. An atypical 3.2 kWp PV system and a 19.2 kWh storage battery brick was determined to be capable of meeting the house's whole daily energy requirements, as well as the defined electrical shutdown times, to simulate the system, which took into account the day load profile, network cutoff times, and monthly radiation from the sun. The collected simulation results showed that during 9 months of each year, the generated PV energy surpasses the load needs, resulting in a maximum battery state-of-charge (SOC) in the range of 74-85%. The generated PV energy is an approximately proportional requirement as during 3 months of minimum solar irradiance (Dec-Feb), whereas the sequence's SOC differs between 40 and 49 % , demonstrating the validity of the proposed photovoltaic system. In January and July, the PV service's daily energy produced ranges between 2.6 and 5.4 kWh/kWp, corresponding to a conversion efficiency of 90% and 66.25%, correspondingly. [ABSTRACT FROM AUTHOR]

Due to intermittent characteristics of wind power generation, battery energy storage system (BESS) has been exploited for decreasing the adverse impact of wind power output on the grid. This paper focuses on the BESS operation strategy called reference compensation for dispatchable wind. By adaptively compensating a reference signal that is typically set to be an average forecasted wind power for certain duration, the BESS maintains its SOC within a proper range, avoiding the non-compliant BESS when it is required to be charged or discharged because it is already fully charged or discharged, respectively, due to the unavoidable forecast errors. The proposed method has been applied to the real world wind farm data which is scaled down for the simulation in order to demonstrate its effectiveness of the proposed method. Simulation results demonstrate that the proposed method can decrease the operation suspension due to non-functioning BESS and keep the BESS on, and help thus enable the wind dispatchability. [ABSTRACT FROM AUTHOR]

An isolated micro-grid has different requirements from the traditional power grids. Several energy sources may be linked for the purpose of sharing load demand without being linked to the grid. The isolated micro-grid is made up of at least one energy generator, an energy storage system, and a load portion. Because there are several energy sources and a range of models, the power flow must be managed to ensure the safety of all hardware. Monitoring the flow of power from multiple energy sources necessitates adherence to many parameters and other requirements. As a result, the goal of this work is to identify a worthwhile solution for providing the appropriate portions with the necessary power while also obtaining the necessary energy from other sources. The approach is based on the fuzzy logic controller, which is an intelligent technology. This regulator is used in an efficient process that tries to control all of the equipment in the isolated micro-grid under investigation. The MATLAB/Simulink platform is employed for simulating this proposed system, and then, the depicted results were discussed and compared. Showing the traditional relay control, the standard PI regulator, and a neural control combination process, the achieved results prove that it is possible to reduce the battery recharge time to half; if the proposed fuzzy controller is used. Then, the established controller specifications have been used for evaluating the energy performances of the hybrid energy system under a real case situation in a specific location in the world. Consequently, the obtained results prove that this proposal power management system will be largely beneficial for such energy storage applications and an energy yield can be assured during all climatic conditions and specifications. [ABSTRACT FROM AUTHOR]

Magnetic core-shell Zn ferrite and carbon dots (C-dots) composite have been synthesized in this work using a simple coprecipitation and hydrothermal process, respectively. X-ray diffraction (XRD) patterns demonstrate an inverse spinel structure of Zn ferrites; the lattice parameter has decreased from 8.19 Å to 8.10 Å with C-dots. Scanning electron microscopy (SEM) images reveal rods-like structures for C-dots, and in the composite case, it is uniformly dispersed using low contrast consecutive C-dot layers to produce a core-shell structure. Zn ferrites are non-uniform in size, whereas C-dots and their composites are in uniform shape according to SEM images. The energy dispersive X-ray (EDX) study indicates that the substitution has been successful. For Zn ferrites, and composite, the Fourier transform infrared (FTIR) spectra shows that the absorption band of the tetrahedral site at 990 cm−1, and 870 cm−1, respectively. Different bonds in the infrared spectrum match specific function groups and bonding in various chemicals. The vibrating sample magnetometry (VSM) results indicates that the composite displays ferrimagnetic behavior. The specific capacity for composite has been found to be 2351 and 1790 F/g using cyclic voltammetry (CV) and galvanostatic charge-discharge (GCD) measurements, respectively. Higher electrochemical performance of the prepared composites may be helpful for energy storage systems. • Optimized device's performance, long-term stability, cost-effective fabrication remain a hurdle in realizing perfect supercapacitor (SC). • Careful substitution of carbon based materials such as carbon dots to metal oxides can be investigated to tune SC performance. • X-ray diffraction (XRD) revealing an inverse spinel structure for Zn ferrites. • SEM images depicting rod-like structures for C-dots forming a core-shell structure. • Enhanced electrochemical performance of the composite with specific capacity (2351 F/g via CV and 1790 F/g via GCD measurements). [ABSTRACT FROM AUTHOR]

[Display omitted] • Band gap tuned BaS 2 :Cu 8 S 5 :LaS trichalcogenide system. • Significant functionality as energy material. • BaS 2 :Cu 8 S 5 :LaS embellished nickel foam electrode. • Charge storage of 1299F/g specific capacitance. • Specific power density of 11166 W kg−1. • Excellent durability and stability. Current work, for the first time, reports the synthesis of the novel BaS 2 :Cu 8 S 5 :LaS ternary chalcogenide for utilization in the energy storage devices owing to its superior capacitive performance. BaS 2 :Cu 8 S 5 :LaS was marked by remarkable optical behavior with the narrowed band gap energy i.e. 2.55 eV. Crystallographic analysis is indicative of the 16.77 nm average crystallite size. The presence of the metal sulphide bonds was confirmed by the vibrational stretches between 420 – 890 cm−1. Rod shaped particles with the suspended spheres was the predominant morphology. With the augmented redox behavior and charging-discharging behavior, fabricated electrode attained the auspicious specific capacitance of 1299F/g. Furthermore, the specific power density obtained for this electrode was 11166 W kg−1. The enhanced electrochemical performance was also exhibited by the elevated electrical conductivity showing the equivalent series resistance (R s) = 0.48 Ω. [ABSTRACT FROM AUTHOR]

Herein, we report nanocomposite of titanium dioxide (TiO 2) nanorods decorated reduced graphene oxide (TiO 2 /RGO) nanocomposite prepared using the simple, one-pot hydrothermal route for electrode material in supercapacitor applications. A systematic comparison study was carried out for the TiO 2 nanorods coated on graphite foil in presence of alkaline media 3 M KOH, NaCl, and Na 2 SO 4 using the three-electrode method. The TiO 2 /RGO composite shows an excellent specific capacitance (C sp) of 330 Fg-1 at the discharge current density 0.5 Ag-1 in presence of 3 M KOH electrolyte solution. The obtained highest specific capacitance values in order by various electrolytes are observed as KOH > NaCl > Na 2 SO 4. The long-term cycle stability of charge and discharge cycle at current density 0.5 Ag-1 over 1000 cycles and only 8% decay in the specific capacitance of TiO 2 /RGO nanocomposite was observed in 3 M KOH electrolyte. The improved electrochemical performance TiO 2 /RGOcomposite in presence of KOH electrolyte is shown to be the most suitable electrode for the supercapacitors. [Display omitted] • Novel binary TiO 2 /RGO composite was prepared through a facile hydrothermal method. • The materials structural, morphological and elemental composition confirmed using XRD, TEM and EDAX techniques. • The electrochemical properties TiO 2 /RGO electrodes were studied in 3 M KOH electrolyte solution. • Pure TiO 2 NRs and TiO 2 /RGO electrodes exhibit higher C sp about 142 and 330 Fg-1 at 0.5 Ag-1 current density. • The capacitance was retained at 92.0% after 1000 charge-discharge cycles at 0.5 A g−1. [ABSTRACT FROM AUTHOR]

[Display omitted] • New silver based 2D MOF was synthesized by sonochemical method. • Structure and reactivity of the material was confirmed by Single-crystal X-ray diffraction and DFT computational studies. • Electrochemical performance was evaluated by CV, GCD and EIS studies via three and two electrodes assembly. • The hybrid device showed cyclic stability of 97.5 % after 5000 cycles. A new silver(I) 2D MOF (Ag-MOF) was synthesized from 3,4-pyridinedicarboxylic acid (PDCA) by sonication method and characterized by single crystal X-ray diffraction, elemental analysis and FTIR spectroscopy. The material was further utilized for DFT computation and electrochemical performance. Theoretical and practical results for Ag-MOF geometrical parameters were found to be in reasonable agreement. Small HOMO-LUMO energy distance of 0.47 eV confirmed that electron transfer was much feasible. Distribution of electron isodensities was elaborated by DFT and FMOs computation. Double redox peaks in CV voltammograms reflected the change in oxidation state. Multiple plateaus in GCD curves showed the pseudo-capacitive behavior. Ag-MOF exhibited 101 Cg−1 specific capacity (Q s), 123 Wh.kg−1 energy density and 12,960 W kg−1 power density at current density of 5 Ag−1. There was a small difference in R ct and R i which revealed that Ag-MOF had great ability to store energy. Presence of semi-circular arc in the EIS spectrum directly dictates the supercapacitor behavior. The electrode showed 97.5 % cyclic stability after 5000 cycles. [ABSTRACT FROM AUTHOR]