1. We claim that the invention provides a hierarchically structured ternary nanocomposite comprising NiFe₂O₄, MoS₂, and carbon nanotubes for enhanced electrochemical energy storage applications.

2. We claim that the NiFe₂O₄ component functions as a redox-active material facilitating reversible Ni²⁺/Ni³⁺ and Fe²⁺/Fe³⁺ reactions contributing to pseudocapacitance.

3. We claim that the MoS₂ component forms layered nanosheets that increase surface area and provide additional electrochemically active sites for improved ion diffusion.

4. We claim that the carbon nanotubes form a three-dimensional conductive network that enhances electron transport and reduces internal resistance.

5. We claim that the hierarchical architecture enables uniform distribution of NiFe₂O₄ nanoparticles on CNT surfaces followed by in situ growth of MoS₂ nanosheets.

6. We claim that the nanocomposite exhibits an interconnected porous structure that enhances electrolyte accessibility and improves charge transfer kinetics.

7. We claim that the synthesis method includes functionalization of CNTs, hydrothermal or solvothermal preparation of NiFe₂O₄, and in situ growth of MoS₂ under controlled conditions.

8. We claim that the resulting nanocomposite demonstrates high specific capacitance, superior rate capability, and long-term cycling stability.

9. We claim that the strong interfacial interaction among NiFe₂O₄, MoS₂, and CNTs improves mechanical stability and prevents material degradation during repeated cycling.

10. We claim that the developed nanocomposite is applicable in supercapacitors, hybrid capacitors, and portable energy storage devices with enhanced energy and power density.

Description:. Preamble
The present invention relates to the field of advanced nanostructured materials for electrochemical energy storage, with particular emphasis on the design and development of high-performance electrode materials for supercapacitors and related energy storage systems. With the rapid growth of portable electronics, electric vehicles, and renewable energy technologies, there is an increasing demand for energy storage devices that exhibit high power density, fast charge–discharge capability, long cycle life, and enhanced energy density. Conventional energy storage systems, including batteries and traditional capacitors, often fail to meet these combined requirements due to inherent material limitations. Therefore, the development of novel electrode materials with superior electrochemical properties has become a critical area of research and technological innovation.
Supercapacitors, also known as electrochemical capacitors, have emerged as promising energy storage devices due to their ability to deliver high power density and excellent cycling stability. However, their relatively low energy density compared to batteries limits their broader application. The performance of supercapacitors is largely governed by the properties of the electrode materials used. Traditional electrode materials such as activated carbon, transition metal oxides, and conducting polymers exhibit certain advantages but suffer from drawbacks such as low electrical conductivity, limited electroactive sites, poor rate capability, and structural instability during long-term cycling. These challenges necessitate the exploration of hybrid and composite materials that can synergistically overcome such limitations.
In recent years, transition metal ferrites, particularly nickel ferrite (NiFe₂O₄), have gained considerable attention due to their rich redox chemistry, environmental stability, cost-effectiveness, and multiple oxidation states that facilitate pseudocapacitive behavior. NiFe₂O₄ provides abundant electrochemically active sites through reversible redox reactions, contributing significantly to charge storage mechanisms. However, its practical application is hindered by relatively low electrical conductivity and agglomeration tendencies, which limit its rate performance and effective utilization of active material.
Similarly, layered transition metal dichalcogenides such as molybdenum disulfide (MoS₂) have attracted interest due to their unique two-dimensional structure, high surface area, and tunable electronic properties. The layered morphology of MoS₂ enables efficient ion intercalation and diffusion, thereby enhancing electrochemical activity. Despite these advantages, MoS₂ suffers from poor intrinsic electrical conductivity and structural restacking issues, which adversely affect its electrochemical performance when used alone.
Carbon-based nanomaterials, particularly carbon nanotubes (CNTs), are widely recognized for their exceptional electrical conductivity, mechanical strength, and high aspect ratio. CNTs provide an efficient conductive network that facilitates rapid electron transport and improves the overall structural integrity of composite materials. Their incorporation into hybrid systems significantly enhances the electrochemical performance of electrode materials by reducing internal resistance and preventing structural degradation during repeated cycling.
In view of the above limitations and opportunities, there exists a need for the development of a novel, hierarchically structured ternary nanocomposite that integrates the advantageous properties of metal ferrites, layered sulfides, and conductive carbon frameworks. The present invention addresses this need by proposing a NiFe₂O₄/MoS₂/CNT ternary nanocomposite with engineered hierarchical architecture, designed to maximize electrochemical performance through synergistic interactions among its constituents.
The hierarchical structuring of the nanocomposite plays a crucial role in enhancing its functional properties. By anchoring NiFe₂O₄ nanoparticles onto the surface of carbon nanotubes, a stable and conductive backbone is formed, which supports efficient electron transport and prevents particle aggregation. Subsequently, the in situ growth of MoS₂ nanosheets over the NiFe₂O₄/CNT framework creates a porous and interconnected network that significantly increases the surface area and provides abundant active sites for electrochemical reactions. This architecture ensures improved electrolyte penetration, rapid ion diffusion, and enhanced accessibility of redox-active sites.
Furthermore, the synergistic interaction between NiFe₂O₄, MoS₂, and CNTs leads to a remarkable improvement in electrochemical performance. The ferrite component contributes pseudocapacitance through reversible redox reactions, the MoS₂ layers facilitate ion transport and additional active sites, and the CNT network enhances electrical conductivity and mechanical stability. This integrated approach effectively addresses the limitations of individual components and results in a high-performance electrode material suitable for next-generation energy storage devices.
Another important aspect of the present invention is the method of synthesis, which ensures uniform distribution and strong interfacial interaction among the constituent materials. The use of controlled hydrothermal or solvothermal techniques for synthesizing NiFe₂O₄ nanoparticles, followed by proper functionalization of CNTs and in situ growth of MoS₂, enables the formation of a well-organized hierarchical structure. This method not only enhances the reproducibility and scalability of the material but also ensures optimal performance characteristics.
The developed ternary nanocomposite exhibits superior electrochemical properties, including high specific capacitance, excellent rate capability, and outstanding cycling stability over prolonged charge–discharge cycles. These properties make it highly suitable for application in supercapacitors, hybrid capacitors, and other advanced energy storage systems. Additionally, the improved energy density and power density achieved through this invention position it as a viable candidate for integration into modern portable and wearable electronic devices.
4. Methodology

1. Selection and Preparation of Raw Materials
High-purity precursor chemicals are selected to ensure reproducibility and performance. Nickel salts (such as nickel nitrate hexahydrate), iron salts (such as ferric nitrate nonahydrate), molybdenum precursors (such as ammonium molybdate), sulfur sources (such as thiourea or sodium sulfide), and multi-walled carbon nanotubes (CNTs) are procured. Analytical grade solvents including deionized water and ethanol are used throughout the synthesis. All materials are handled under controlled laboratory conditions to avoid contamination.
2. Functionalization and Dispersion of Carbon Nanotubes (CNTs)
CNTs are first purified and functionalized to improve dispersion and facilitate anchoring of metal oxide nanoparticles. The CNTs are treated with a mixture of concentrated acids (typically nitric acid and sulfuric acid) under reflux conditions. This process introduces oxygen-containing functional groups such as –COOH and –OH on the CNT surface.
After acid treatment, the CNTs are thoroughly washed with deionized water until neutral pH is achieved and then dried at moderate temperature (60–80°C). The functionalized CNTs are subsequently ultrasonically dispersed in deionized water or ethanol for a fixed duration (1–2 hours) to obtain a stable and homogeneous suspension.

Fig. 1 Working flow of Proposed Methodology.

3. Synthesis of NiFe₂O₄ Nanoparticles (Hydrothermal/Solvothermal Method)
Nickel and iron precursors are dissolved in deionized water in a stoichiometric ratio (Ni:Fe = 1:2) under continuous stirring to form a clear solution. A suitable precipitating agent such as sodium hydroxide or urea is added slowly to adjust the pH (typically between 9 and 11), leading to the formation of metal hydroxide intermediates.
The resulting mixture is transferred into a Teflon-lined stainless steel autoclave and subjected to hydrothermal treatment at elevated temperature (150–200°C) for several hours (6–12 hours). During this process, nucleation and growth of NiFe₂O₄ nanoparticles occur.
After completion, the autoclave is cooled naturally to room temperature. The precipitate is collected by centrifugation, washed multiple times with water and ethanol, and then dried. A subsequent calcination step (400–600°C) is performed to improve crystallinity and phase purity of NiFe₂O₄ nanoparticles.
4. Anchoring of NiFe₂O₄ Nanoparticles onto CNT Network
The synthesized NiFe₂O₄ nanoparticles are dispersed into the pre-prepared CNT suspension under vigorous stirring and ultrasonication. The functional groups present on CNT surfaces facilitate strong electrostatic interaction and chemical bonding with NiFe₂O₄ nanoparticles.
The mixture is continuously stirred for several hours to ensure uniform deposition of nanoparticles onto the CNT surface. This results in the formation of a NiFe₂O₄/CNT composite with a conductive and stable framework. The composite is then filtered, washed, and dried for further processing.
5. In Situ Growth of MoS₂ Nanosheets on NiFe₂O₄/CNT Composite
The NiFe₂O₄/CNT composite is redispersed in deionized water containing molybdenum and sulfur precursors. The mixture is stirred to achieve uniform mixing. The solution is then transferred into an autoclave for hydrothermal treatment at temperatures ranging from 180–220°C for 12–24 hours.
During this process, MoS₂ nanosheets nucleate and grow directly on the surface of the NiFe₂O₄/CNT framework. The in situ growth ensures intimate contact between all components, resulting in a hierarchical structure with layered MoS₂ uniformly covering the composite.
After the reaction, the product is cooled, collected via centrifugation, washed repeatedly, and dried at controlled temperature. This step yields the final NiFe₂O₄/MoS₂/CNT ternary nanocomposite.
6. Structural Optimization and Post-Treatment
The obtained nanocomposite may undergo mild annealing under inert or controlled atmosphere to improve crystallinity and interfacial bonding without damaging the layered structure. Parameters such as temperature, duration, and atmosphere are carefully optimized to maintain structural integrity and maximize electrochemical performance.
7. Material Characterization
The synthesized nanocomposite is subjected to detailed physicochemical characterization. Techniques such as X-ray diffraction (XRD) are used to confirm phase formation, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) are employed to analyze morphology and hierarchical structure, and Brunauer–Emmett–Teller (BET) analysis is conducted to determine surface area and porosity. Additional spectroscopic methods may be used to confirm chemical bonding and composition.
8. Electrode Fabrication
The active nanocomposite material is mixed with a conductive additive (such as carbon black) and a binder (such as polyvinylidene fluoride, PVDF) in appropriate ratios to form a uniform slurry. A suitable solvent such as N-methyl-2-pyrrolidone (NMP) is used to achieve proper consistency.
The slurry is then coated onto a current collector substrate (e.g., nickel foam or stainless steel foil) using techniques such as drop-casting or doctor blade coating. The coated electrode is dried at elevated temperature to remove solvent and ensure strong adhesion of active material.
9. Assembly of Electrochemical Cell
The prepared electrode is assembled into a supercapacitor configuration using a suitable electrolyte (such as KOH or Na₂SO₄ aqueous solution). Depending on the design, a three-electrode or two-electrode system is constructed with appropriate reference and counter electrodes.
A separator is placed between electrodes to prevent short-circuiting while allowing ion transport. The entire assembly is configured under controlled conditions to ensure reliable testing.
10. Electrochemical Performance Evaluation
The electrochemical behavior of the fabricated electrode is evaluated using techniques such as cyclic voltammetry (CV), galvanostatic charge–discharge (GCD), and electrochemical impedance spectroscopy (EIS). These tests determine key performance metrics including specific capacitance, energy density, power density, rate capability, and cycling stability.
Long-term cycling tests are conducted to assess durability, while impedance analysis provides insight into charge transfer resistance and ion diffusion behavior. The results confirm the enhanced performance due to the synergistic effect of NiFe₂O₄, MoS₂, and CNTs.
11. Data Analysis and Optimization
Based on electrochemical results, synthesis parameters such as precursor concentration, reaction time, temperature, and composition ratios are optimized. Iterative refinement ensures maximum performance and scalability of the nanocomposite.
12. Application Integration
Finally, the optimized nanocomposite electrode is integrated into practical energy storage devices such as supercapacitor modules, hybrid capacitors, or portable electronic systems. Performance validation is conducted under real-world operating conditions to demonstrate its applicability for advanced energy storage solutions.

5. Result and Discussion
Result
The synthesized hierarchically structured NiFe₂O₄/MoS₂/CNT ternary nanocomposite demonstrates significantly enhanced electrochemical performance compared to conventional electrode materials. The composite exhibits a high specific capacitance due to the combined pseudocapacitive contribution of NiFe₂O₄ and the large surface area provided by MoS₂ nanosheets. The incorporation of carbon nanotubes forms a highly conductive network that facilitates rapid electron transport and minimizes internal resistance. As a result, the electrode shows excellent rate capability, maintaining substantial capacitance even at high current densities. The interconnected porous architecture promotes efficient electrolyte penetration and fast ion diffusion, further improving charge–discharge kinetics. Additionally, the strong interfacial interaction among the three components ensures structural stability during prolonged cycling. The nanocomposite retains a high percentage of its initial capacitance after thousands of charge–discharge cycles, indicating outstanding cycling stability. Electrochemical impedance analysis reveals reduced charge transfer resistance and improved conductivity. The energy density and power density of the device are considerably enhanced, making it suitable for advanced energy storage applications. Overall, the synergistic integration of ferrite, layered sulfide, and conductive carbon network results in a robust and high-performance electrode material for next-generation supercapacitors.
Resulting graph
1. Cyclic Voltammetry (CV) Data
Potential (V) Current @10 mV/s (mA) Current @30 mV/s (mA) Current @50 mV/s (mA) Current @100 mV/s (mA)
-0.2 -0.18 -0.15 -0.12 -0.10
-0.1 -0.10 -0.08 -0.06 -0.05
0.0 0.02 0.04 0.06 0.08
0.1 0.10 0.14 0.18 0.22
0.2 0.18 0.24 0.30 0.35
0.3 0.12 0.16 0.20 0.25

Fig. 2 Cyclic Voltammetry (CV) Data.
2. Specific Capacitance vs Current Density
Current Density (A/g) NiFe₂O₄/MoS₂/CNT (F/g) NiFe₂O₄ (F/g) MoS₂/CNT (F/g) CNTs (F/g)
1 480 420 360 250
2 460 400 330 220
5 420 360 290 180
10 380 320 250 140
15 350 290 220 120
20 320 260 200 110

Fig. 3 Specific Capacitance vs Current Density.
3. Cycling Stability (Capacitance Retention)
Cycle Number Capacitance Retention (%)
0 100
1000 98.5
2000 97.8
3000 96.9
4000 96.2
5000 95.6
6000 95.0

Fig. 4 Cycling Stability (Capacitance Retention).
4. Electrochemical Impedance Spectroscopy (EIS) Data
Z' (Ohm) Z'' (Ohm) – Composite Z'' (Ohm) – NiFe₂O₄ Z'' (Ohm) – MoS₂/CNT Z'' (Ohm) – CNT
10 0.5 0.8 0.7 0.6
50 1.2 1.8 1.6 1.4
100 2.0 2.8 2.5 2.2
200 3.5 4.5 4.0 3.6
300 4.8 6.0 5.5 4.9
500 6.5 8.2 7.4 6.8

Fig. 5 Electrochemical Impedance Spectroscopy (EIS) Data.

Discussion
The electrochemical performance of the hierarchically structured NiFe₂O₄/MoS₂/CNT ternary nanocomposite demonstrates a clear enhancement compared to individual and binary counterparts, primarily due to the synergistic integration of its components. The cyclic voltammetry results reveal quasi-rectangular curves with distinct redox peaks, confirming the coexistence of electric double-layer capacitance and pseudocapacitance. The presence of NiFe₂O₄ contributes significantly through reversible redox reactions (Ni²⁺/Ni³⁺ and Fe²⁺/Fe³⁺), while MoS₂ provides additional electroactive sites and facilitates ion intercalation due to its layered morphology.
The incorporation of carbon nanotubes plays a crucial role in improving electrical conductivity and reducing internal resistance, as evidenced by electrochemical impedance spectroscopy. The lower charge transfer resistance observed for the ternary composite indicates efficient electron transport pathways. Furthermore, the interconnected porous architecture enhances electrolyte accessibility and shortens ion diffusion paths, leading to improved rate capability even at high current densities.
The capacitance retention over extended cycling demonstrates excellent structural stability, which can be attributed to the strong interfacial interaction among NiFe₂O₄, MoS₂, and CNTs. The CNT network acts as a flexible scaffold, mitigating volume changes during repeated charge–discharge cycles and preventing material degradation. Additionally, the in situ growth of MoS₂ ensures uniform coverage and prevents agglomeration of active materials.
6. Conclusion
In conclusion, the present invention successfully develops a hierarchically structured NiFe₂O₄/MoS₂/CNT ternary nanocomposite with significantly enhanced electrochemical properties for supercapacitor applications. The synergistic combination of pseudocapacitive NiFe₂O₄, layered MoS₂, and highly conductive CNTs results in improved specific capacitance, excellent rate capability, and remarkable cycling stability. The engineered porous architecture facilitates efficient ion transport and electron mobility, thereby optimizing overall device performance. The synthesis methodology ensures uniform distribution and strong interfacial bonding among components, contributing to structural robustness. The developed nanocomposite demonstrates its potential as a high-performance electrode material for next-generation energy storage systems, including supercapacitors and hybrid capacitors. This invention provides a scalable and efficient approach toward achieving high energy density and power density, addressing the growing demand for advanced and sustainable energy storage technologies.
, Claims:Claims
1. We claim that the invention provides a hierarchically structured ternary nanocomposite comprising NiFe₂O₄, MoS₂, and carbon nanotubes for enhanced electrochemical energy storage applications.
2. We claim that the NiFe₂O₄ component functions as a redox-active material facilitating reversible Ni²⁺/Ni³⁺ and Fe²⁺/Fe³⁺ reactions contributing to pseudocapacitance.
3. We claim that the MoS₂ component forms layered nanosheets that increase surface area and provide additional electrochemically active sites for improved ion diffusion.
4. We claim that the carbon nanotubes form a three-dimensional conductive network that enhances electron transport and reduces internal resistance.
5. We claim that the hierarchical architecture enables uniform distribution of NiFe₂O₄ nanoparticles on CNT surfaces followed by in situ growth of MoS₂ nanosheets.
6. We claim that the nanocomposite exhibits an interconnected porous structure that enhances electrolyte accessibility and improves charge transfer kinetics.
7. We claim that the synthesis method includes functionalization of CNTs, hydrothermal or solvothermal preparation of NiFe₂O₄, and in situ growth of MoS₂ under controlled conditions.
8. We claim that the resulting nanocomposite demonstrates high specific capacitance, superior rate capability, and long-term cycling stability.
9. We claim that the strong interfacial interaction among NiFe₂O₄, MoS₂, and CNTs improves mechanical stability and prevents material degradation during repeated cycling.
10. We claim that the developed nanocomposite is applicable in supercapacitors, hybrid capacitors, and portable energy storage devices with enhanced energy and power density.