KR20220123173A - A heterostructured (SmCoO3/rGO) material and a method of manufacture thereof - Google Patents

Abstract

The present invention provides an ingenious method for preparing a SmCoO_3/rGO material with an improved heterogeneous structure using a solvothermal method. First, graphene oxide is prepared through improved hummer technology, and the prepared graphene oxide is subjected to a hydrothermal process at about 120℃ for 5 hours to prepare a uniform solution of reduced graphene oxide (rGO). In addition, samarium cobalt oxide (SmCoO_3) is synthesized by mixing samarium (III) nitrate, cobalt nitrate hexahydrate, and urea at a ratio of 1:2:8 and dissolving the same in 80 mL of a mixed solution of deionized water and ethanol. Then, 0.2 g of rGO is dispersed in SmCoO_3 to create a uniform solution of SmCoO_3/rGO. Further, the solution is calcined in an autoclave to form a SmCoO_3/rGO material with a heterogeneous structure. Accordingly, provided is a method of designing an improved electrode material for a supercapacitor.

Description

A heterostructured (SmCoO3/rGO) material and a method of manufacture thereof

The present invention relates to the field of supercapacitors. More particularly, the present invention relates to a method for manufacturing a hybrid supercapacitor device by synthesizing an improved SmCoO ₃ /rGO (samarium cobalt oxide-decorated reduced graphene oxide) electrode material.

The recent technological development of energy-based materials has made the energy storage field one of the promising fields for future research. Despite some energy-driven technology requirements, storage devices such as capacitors and batteries are losing dominance. Batteries provide good energy density whereas capacitors provide high quality power density, but nevertheless, in contrast, the power density of batteries and the energy density of capacitors are low. In this context, supercapacitors, thanks to their unique capabilities, have proven to be very important as these two advantages combine.

Supercapacitors are well-known energy-saving devices with advantages such as high power density, long lifespan, and excellent charge and discharge times required for batteries and fuel cells. Recently, composite-based supercapacitors have attracted more attention as more environmentally friendly and more capable candidates for energy saving applications. Carbonaceous materials have been investigated because of their energy-saving electrostatic mechanism, maintaining low cost for relatively very long cycles. Moreover, the elements of the transition metal oxide series are attractive compared to those of carbon-based materials and are considered effective electrode materials for supercapacitor applications, which can ensure high-efficiency storage of electrochemical energy. However, rare earth (RE) metal oxides are very important for research because of their excellent electrochemical redox properties, low cost and high environmental safety. Rare earths (RE) have various valences, among which the RE ³⁺ ion is the most common trivalent ion. Two unique chemical processes are used in the use of rare earth oxides (REOs): acid-base reactions and redox reactions. Rare earth oxides are considered the best candidates for pseudo capacitors due to their excellent redox properties. Samarium of the rare earth oxide (REO) group has various oxidation states (Sm ³⁺ , Sm ²⁺ , Sm ¹⁺ ).

Today, nanostructured metal oxides are widely used in supercapacitor and solar cell based applications. In general, binary and ternary metal oxides are considered excellent electrode materials due to their excellent properties such as high capacity from redox reactions. MnCo ₂ O ₄ , NiCo ₂ O ₄ , CoMn ₂ O ₄ and SmCoO ₃ are some types of binary metal oxides. Here, SmCoO ₃ exhibits excellent properties in these various types of binary metal oxides due to its excellent physicochemical and electrochemical properties. The most important characteristic of samarium (Sm) is its high storage capacity. As a result, cobalt provides a higher oxidation potential and samarium can store more electrons. Because rare earth (RE) metals have several unique properties that provide large surface area, small size and interfacial effect, the cooperative effect of rare earth (RE) elements with transition metal oxides has been intensively studied in the field of electrochemistry. .

An important purpose of choosing samarium (Sm) as a composite material is its high storage capacity. Sm ³⁺ ions have a large ionic radius, and the strong bonding force of Sm-O forms a stable crystal lattice, making it possible to obtain anode materials. The Sm ³⁺ cation high-quality electronic conductivity may enable better charge transport and insertion processes. Samarium (Sm) components stabilize the crystal structure, provide better morphology, and provide better battery performance with improved cycle life. In recent years, the trend towards electrode materials based on metal oxides decorated with carbon-based materials continues.

Nowadays, reduced graphene oxides (rGOs), such as carbon materials, are combined with these nanomaterials to increase their surface area and form graphene layers. Therefore, when rGO is dispersed with SmCoO ₃ , diffusion of the electrolyte through the electrode is promoted, which greatly reduces the internal resistance of the material. A well-synthesized heterostructure plays an important role in enhancing the performance of the electrode.

Therefore, in light of the above review, there is a long-standing need for a method to fabricate improved electrode materials with better electrochemical properties, thereby serving as better alternative materials in supercapacitor-based energy storage devices. .

The main object of the present invention is to provide a method for designing an improved electrode material for a supercapacitor.

Another object of the present invention is to provide a method for synthesizing a heterostructured flower-shaped SmCoO ₃ /rGO electrode material.

Another object of the present invention is to provide a basic characterization technique for calculating the physicochemical properties of electrode materials.

Another object of the present invention is to provide a method using a solvothermal method for synthesizing an electrode material.

Another object of the present invention is to provide a method for manufacturing a hybrid two-electrode SmCoO ₃ /rGO//AC (activated carbon used for AC-2 electrode device fabrication) assembly.

The present invention presents a method for synthesizing a samarium cobalt oxide-decorated reduced graphene oxide (SmCoO ₃ /rGO) material by a solvothermal method. First, graphene oxide is prepared through the improved Hummer technology. Then, a reduced graphene oxide (rGO) homogeneous solution is generated by subjecting the graphene oxide obtained therefrom to a hydrothermal process at about 120° C. for 5 hours. In addition, for the synthesis of samarium cobalt oxide, samarium (III) nitrate, cobalt nitrate hexahydrate and urea are mixed in a ratio of 1:2:8 and dissolved in 80 mL of a mixed solution of deionized water and ethanol. Furthermore, 0.2 g of the prepared rGO was dispersed in SmCoO ₃ to produce a homogeneous SmCoO ₃ /rGO solution.

Then, to fabricate a hybrid two-electrode SmCoO ₃ /rGO//AC assembly, the SmCoO ₃ /rGO material is subjected to a characterization process to perform qualitative and quantitative tests, in which SmCoO ₃ /rGO is used as the cathode and activated carbon. is used as an anode. A nickel foam coated with an active material (SmCoO ₃ /rGO) is used as the current collector. 2 mg of the active material is coated on an area of 1 cm × 1 cm of Ni foam for a positive electrode, and 5 mg of the active material is coated on an area of 1 cm × 1 cm of Ni foam for a negative electrode. Also, a few drops of potassium hydroxide (KOH) are poured onto both the Ni foam electrodes of the positive and negative electrodes coated with the active material. A Whatman filter paper immersed in potassium hydroxide electrolyte is inserted between the anode and the cathode. Finally, the hybrid two-electrode SmCoO ₃ /rGO//AC assembly is fabricated by tightly packing an array of anode, separator and cathode.

The heterostructured SmCoO ₃ /rGO electrode material of the present invention having the configuration as described above can guarantee better electrochemical performance.

BRIEF DESCRIPTION OF THE DRAWINGS The invention is illustrated in the accompanying drawings, wherein throughout, like reference characters indicate corresponding parts in the various drawings.
BRIEF DESCRIPTION OF THE DRAWINGS Embodiments of the present specification will be better understood from the following description with reference to the drawings.
1 illustrates a method 100 for preparing various samples in accordance with one embodiment of the present invention.
FIG. 2 shows a method 200 for preparing an SmCoO ₃ /rGO electrode material.
3 shows the XRD patterns of rGO, SmCoO ₃ , SmCoO ₃ /rGO materials synthesized using the solvothermal method.
4A shows a bar chart showing specific capacitance from cyclic voltammetry (CV) curves of SmCoO ₃ and SmCoO ₃ /rGO materials in accordance with an embodiment of the present invention.
4B shows a bar chart showing the specific capacitance from a constant current charge/discharge (GCD) curve of SmCoO ₃ and SmCoO ₃ /rGO materials according to an embodiment of the present invention.
5 shows a cycle graph showing capacitance retention and Columbic efficiency of a hybrid two-electrode SmCoO ₃ /rGO//AC supercapacitor assembly according to an embodiment of the present invention.
6 shows the heterostructured morphology of SmCoO ₃ and SmCoO 3 /rGO materials according to an embodiment of the present invention.
7 is a non-electrostatic calculated from a galvanostatic charge/discharge (GCD) plot of a hybrid two-electrode SmCoO ₃ /rGO//AC supercapacitor assembly according to an embodiment of the present invention; A table showing capacity, energy density and power density is shown.

The following implementations and their various features and advantageous details are more fully described in the following description with reference to the accompanying drawings and/or non-limiting embodiments set forth in the detailed description. Descriptions of well-known components and process techniques are omitted so as not to unnecessarily obscure the embodiments herein. The examples used herein are merely intended to facilitate an understanding of how embodiments of the present invention may be practiced herein and to enable those skilled in the art to practice the embodiments herein. Accordingly, the above embodiments should not be construed as limiting the protection scope of the present specification.

The examples below provide details of a method for preparing samarium cobalt oxide-decorated reduced graphene oxide (SmCoO ₃ /rGO) using a solvothermal method, wherein the homogeneous solution is at a specific temperature and time. calcined in an autoclave. In the present invention, the electrode is fabricated in a manner that provides improved electrochemical performance through effective energy density, specific capacity and power density in supercapacitor application electrodes. The improved electrochemical performance allows the electrode to act as an excellent material for a supercapacitor, thereby improving the energy storage performance inside the supercapacitor.

The present invention provides a novel method for synthesizing a samarium cobalt oxide-decorated reduced graphene oxide (SmCoO ₃ /rGO) material. The samarium cobalt oxide-decorated reduced graphene oxide is hereinafter referred to as SmCoO ₃ /rGO. First, graphene oxide is prepared through an improved hummers technique. Then, a reduced graphene oxide (rGO) homogeneous solution is produced by subjecting the resulting graphene oxide to a hydrothermal process at about 120° C. for 5 hours. The graphene oxide is hereinafter referred to as rGO. In addition, to synthesize samarium cobalt oxide, samarium (III) nitrate, cobalt nitrate hexahydrate and urea are mixed in a ratio of 1:2:8 and dissolved in 80 mL of a mixed solution of deionized water and ethanol. As a result, a uniform samarium cobalt oxide (SmCoO ₃ ) solution is obtained. The samarium cobalt oxide is referred to as SmCoO ₃ hereinafter. Furthermore, 0.2 g of the prepared rGO is dispersed in SmCoO ₃ to produce a homogeneous SmCoO ₃ /rGO solution, which appears dark brown when SmCoO ₃ /rGO is formed.

In addition, individual samples were produced by separately maintaining the prepared rGO, SmCoO ₃ , SmCoO ₃ /rGO homogeneous solution in an autoclave at a temperature of approximately 180° C. for 12 hours. The sample is then calcined at about 400° C. for 3 hours.

SmCoO ₃ The resulting equilibrium chemical equation is:

Co(NO ₃ ) ₂ + 2Sm(NO ₃ ) ₃ + 8CO(NH ₂ ) ₂ → 2SmCoO ₃ + 8CO ₂ + 13N ₂ + 16H ₂ O

In one embodiment of the present invention, the calcined SmCoO ₃ /rGO material is used to fabricate the electrode. The calcined SmCoO ₃ /rGO material is coated on the surface of a nickel foam, which is cleaned prior to coating each sample.

In the present invention, a nickel foam having a size of (2 cm×1 cm) and a coating area of 1 cm ² and a coating sample of 2 mg (SmCoO ₃ /rGO) are used to prepare the electrode.

In another embodiment of the present invention, similar to the electrode fabrication as described above using the calcined SmCoO ₃ /rGO material, another electrode is prepared using the calcined SmCoO ₃ material.

Subsequently, the SmCoO ₃ and SmCoO ₃ /rGO electrodes are characterized to perform qualitative and quantitative examination of the electrodes. In addition, the characterized SmCoO ₃ /rGO electrode is used for the fabrication of a hybrid two-electrode SmCoO ₃ /rGO//AC assembly, where SmCoO ₃ /rGO is used as the cathode and activated carbon is used as the anode.

In the present invention, the activated carbon acts as a cathode electrode, and the electrochemical properties and specific capacitance of the SmCoO ₃ /rGO electrode have a potential window of (0V) to (0.5V) under various current densities of 1 to 6Ag ^-1 ( is tested within the potential window).

In addition, the potentials of activated carbon and SmCoO ₃ /rGO are fixed in the two-electrode assembly of -1 to 0 V and 0 to 0.6 V, respectively. A nickel foam with a size of 2 cm x 1 cm coated with an active material (SmCoO ₃ /rGO) on an area of 1 cm × 1 cm is used as a current collector. 2 mg of the active material is coated on a Ni foam for a positive electrode having an area of 1 cm×1 cm, and 5 mg of an active material is coated on a Ni foam for a negative electrode with an area of 1 cm×1 cm. The physical structure of the current collector plays an important role in improving the energy density of the supercapacitor. The porous structure of the nickel foam provides better mechanical strength and allows easy access of the electrolyte in any electrochemical charge storage device for charge transport. Furthermore, a few drops of potassium hydroxide (KOH) are poured onto both the active material coated positive and negative NI-foam electrodes.

A Whatman filter paper immersed in potassium hydroxide electrolyte is sandwiched between the positive electrode and the negative electrode, where the Whatman filter paper serves as a non-porous separator. The non-porous nature of the filter paper allows better diffusion of ions into the pores of the electrodes. Finally, the hybrid two-electrode SmCoO ₃ /rGO//AC assembly is fabricated by tightly packing the arrangement of the anode, separator and cathode.

In a preferred embodiment of the present invention, the SmCoO ₃ /rGO sample is used for the fabrication of the hybrid two-electrode SmCoO ₃ /rGO//AC assembly. The SmCoO ₃ /rGO electrode exhibits improved electrochemical performance, including high capacitive retention and columbic efficiency, where 74.28% of capacitive retention is 15,000 charge-discharge. persists after cycle.

In one embodiment of the present invention, the hybrid two-electrode SmCoO ₃ /rGO//AC supercapacitor assembly has an energy density of 52 Wh/Kg , a power density of 752 W/Kg and a specific capacitance at 1 A/g (current density). 166 F/g.

In the present invention, Wh/Kg is watt-hour per kilogram for a particular energy, where energy density represents the amount of energy the supercapacitor stores with respect to its mass. F/g is farad/gram of specific capacitance, and A/g is ampere/gram of power density, where the power density represents the amount of power generated by the supercapacitor in relation to its mass.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to the drawings, like reference characters consistently indicate corresponding technical features throughout the drawings and are presented in preferred embodiments.

1 illustrates a method 100 for preparing various samples in accordance with one embodiment of the present invention.

At step 102, the process of making the various samples begins. Graphene oxide is prepared via an advanced Hummer technique and is described in step 104.

Also in step 106, a homogeneous solution of reduced graphene oxide (rGO) is produced by subjecting the resultant graphene oxide to a hydrothermal process at about 120° C. for 5 hours. Furthermore, as shown in step 108, samarium (III) nitrate, cobalt nitrate hexahydrate, and urea were mixed in a ratio of 1:2:8 and dissolved in 80 mL of a mixed solution of deionized water and ethanol to dissolve samarium A homogeneous solution of cobalt oxide (SmCoO ₃ ) is prepared.

In step 110, 0.2 g of the prepared rGO is dispersed in SmCoO ₃ to form a homogeneous SmCoO ₃ /rGO solution, and dark brown appears when SmCoO ₃ /rGO is formed. Also, as shown in step 112, the prepared rGO, SmCoO ₃ and SmCoO ₃ /rGO homogeneous solutions were separately stored in an autoclave maintained at about 180° C. for 12 hours to prepare each sample. Finally, in step 114, the samples are calcined at approximately 400° C. for 3 hours.

FIG. 2 shows a method 200 for preparing an SmCoO ₃ /rGO electrode material. In step 202, a method for fabricating the SmCoO ₃ /rGO electrode material is initiated within the fabrication system. The prepared calcined SmCoO ₃ /rGO material prepared for making the SmCoO ₃ /rGO electrode is described in step 204 .

Also, in step 306 the nickel foam material is cleaned. The calcined SmCoO ₃ /rGO sample is coated on the surface of the nickel foam, as shown in step 208.

In the present invention, a nickel foam having a size of (2×1 cm) and a coating area of 1 cm ² and a coating sample of 2 mg (SmCoO ₃ /rGO) are used to produce a heterostructured SmCoO ₃ /rGO electrode.

In the present invention, the prepared SmCoO ₃ /rGO and SmCoO ₃ materials exhibit a heterogeneous structure. The SmCoO ₃ material exhibits a spherical structure in the case of samarium, and a red hair-covered flower-like structure in the case of cobalt oxide _. show the same shape. The binary metal oxide of the heterostructure is widely used as a supercapacitor electrode and provides excellent electrochemical performance. The binary metal oxide of the heterostructure has a lot of redox activity, and its stability and conductivity are further improved during hybridization. increases This shortens the diffusion path and improves the surface area of the product. Other sizes provide better redox activity by ion transport.

In addition, the specific capacitance, energy density and power density of SmCoO ₃ /rGO and SmCoO ₃ electrodes were evaluated using various formats, and the synthesized rGO, SmCoO ₃ /rGO and SmCoO ₃ samples were characterized to study their various properties. processed From this analysis, the SmCoO ₃ /rGO sample exhibits improved specific capacitance, energy density and power density, and is therefore considered for the fabrication of the hybrid two-electrode SmCoO ₃ /rGO//AC assembly.

In the present invention, the specific capacitance of the SmCoO ₃ /rGO and SmCoO ₃ samples is calculated through Equation 1-2 below.

[Equation 1]

Specific capacitance from CV:

[Equation 2]

Specific capacitance from GCD:

In Equations 1 and 2 as described above, integral Idv is the integral CV curve area, Δt is the discharge time (sec), dv is the applied potential window (V), v is the scan rate (mV / s), m is the active mass (in milligrams) of the prepared SmCoO ₃ /rGO and SmCoO ₃ samples.

Various scan rates are used in the potential range of 0-0.6 V for CV (Cyclic Voltammetry) electro-chemical technique, current density of 1-6 Ag ^-1 , and potential range of 0-0.5 V for galvonastatic charge discharge (GCD). do. The CV technique measures the current generated in the sample, the technique is performed by cycling the potential of the working electrode, and the resulting current is measured. The resulting measured current density shows the superior discharge time and highest capacity in the SmCoO ₃ /rGO material compared to the SmCoO ₃ material. Moreover, the specific capacitances calculated from GCD at 1 A/g current density show 20.69 mAh/g for SmCoO ₃ material and 30.83 mAh/g for SmCoO ₃ /rGO material.

According to various characterization studies of SmCoO ₃ /rGO and SmCoO ₃ materials, SmCoO ₃ /rGO material showed better performance, thereby for the fabrication of the hybrid two-electrode SmCoO ₃ /rGO//AC supercapacitor assembly. are considered A SmCoO ₃ /rGO material is used as the cathode, and activated carbon is used as the anode.

In addition, the activated carbon and SmCoO ₃ /rGO potentials were fixed to the two electrode assembly at -1 to 0 V and 0 to 0.6 V, respectively. A nickel foam with a size of 2 x 1 cm coated with an active material (SmCoO ₃ /rGO) on an area of 1 cm × 1 cm is used as a current collector. 2 mg of the active material is coated on an area of 1 cm × 1 cm of Ni foam for a positive electrode, and 5 mg of the active material is coated on an area of 1 cm × 1 cm of Ni foam for a negative electrode. Furthermore, a few drops of potassium hydroxide (KOH) are poured onto both the positive and negative NI foam electrodes coated with the active material. A Whatman filter paper immersed in potassium hydroxide electrolyte is inserted between the anode and the cathode. Finally, a hybrid two-electrode SmCoO ₃ /rGO//AC assembly is fabricated by tightly packing the arrangement of the anode, separator and cathode.

In an embodiment of the present invention, the specific energy of the hybrid two-electrode SmCoO ₃ /rGO//AC assembly is calculated using Equation 3 below.

[Equation 3]

는 전압(V) 단위의 전위 창이다. 상기 하이브리드 2-전극 SmCoO₃/rGO//AC 슈퍼 커패시터 어셈블리는 1A/g 전류 밀도에서, 52 Wh/Kg 에너지 밀도, 752 W/Kg 전력 밀도 및 166 F/g 비정전용량을 제공한다. In Equation 3 as described above, E is specific energy (energy density) in units of Wh/kg, C is ASC specific capacitance in units of F/g,

is the potential window in voltage (V). The hybrid two-electrode SmCoO ₃ /rGO//AC supercapacitor assembly provides 52 Wh/Kg energy density, 752 W/Kg power density and 166 F/g specific capacitance at 1 A/g current density.

In the present invention, the power density of the SmCoO ₃ /rGO sample is calculated using Equation 4 below.

[Equation 4]

는 방전 시간(초)이다. 상기 하이브리드 2-전극 SmCoO₃/rGO//AC 슈퍼 커패시터 어셈블리는 752 W/kg의 전력 밀도를 제공한다. In Equation 4 above, P is the power density (W/kg) and

is the discharge time in seconds. The hybrid two-electrode SmCoO ₃ /rGO//AC supercapacitor assembly provides a power density of 752 W/kg.

Moreover, the hybrid two-electrode SmCoO ₃ /rGO//AC supercapacitor assembly exhibits improved electrochemical performance including high capacitive retention and Columbic efficiency, where 74.28% capacitive retention is 15,000 charges. - Remains even after a discharge cycle.

Figure 3 shows the XRD pattern of the synthesized rGO, SmCoO ₃ , SmCoO ₃ /rGO material obtained using the solvothermal method according to an embodiment of the present invention. The XRD pattern is related to the standard JCPDS card number 75-0282. The XRD patterns are 24.27 (002), 42.62 (100) of rGO, and 23.72 (100), 33.77 (110), 41.67 (111), 48.42 (200), 60.42 (211) given to the lattice plane of SmCoO ₃ . , 71.02(220), show two characteristic peaks at 2q, indicating the cubic structure of the Pm3m(221) space group in the case of SmCoO ₃ /rGO. The small peak in (002) represents rGO of SmCoO ₃ /rGO.

4A shows a bar chart representing specific capacitance from cyclic voltammetry (CV) curves for SmCoO ₃ /rGO and SmCoO ₃ materials according to an embodiment of the present invention.

4B shows a bar chart representing specific capacitance from galvanostatic charge/discharge (GCD) curves for SmCoO ₃ /rGO and SmCoO 3 materials according to an embodiment of the present invention.

In both FIGS. 4a and 4b , the SmCoO ₃ /rGO material exhibits higher specific capacitance values compared to the SmCoO ₃ material.

5 is a cyclic graph showing capacitance retention and Columbic efficiency of a hybrid two-electrode SmCoO ₃ /rGO//AC supercapacitor assembly according to an embodiment of the present invention. After completing 15,000 charge-discharge cycles, 74.28% capacity is maintained and 98.26% Colombic efficiency is maintained from the GCD profile.

6 shows the heterostructure morphology of SmCoO ₃ /rGO and SmCoO ₃ materials according to an embodiment of the present invention. 6a shows a SmCoO 3 material exhibiting a spherical structure in samarium and a flower-like structure covered with red hairs in cobalt oxide, and FIG. 6b shows a SmCoO ₃ material exhibiting a sheet-like morphology with mixed ball, rod and flower-like structures _. /rGO represents the material. The heterostructure materials described above provide excellent electrochemical performance. The heterostructure aids electrolyte penetration and increases the electrode/electrolyte contact area to improve the electrochemical performance of whole-cell asymmetric solid-state devices. Moreover, the presence of heterostructures in the SmCoO ₃ /rGO material is confirmed by transmission electron microscopy (TEM) image analysis (not shown in the figure). The heterostructure arrangement using rGO-decorated SmCoO ₃ promotes molecular absorption, creates more surface sites at the electrode-electrolyte interface for battery-type Faraday reactions, improves ion transport, and is more useful in supercapacitor applications. It provides great efficiency. Moreover, while these types of sharp-ended nanoflowers are very sensitive to ions during electrochemical reactions, all sharp needles, such as stems, actively contribute to redox reactions and favor migration with high activity and robustness.

7 shows the calculated energy density and power density in a galvanostatic charge/discharge GCD plot in a 1.5 (V) potential window of a hybrid two-electrode SmCoO ₃ /rGO//AC supercapacitor assembly according to an embodiment of the present invention. show the table

The potential window is plotted against discharge time in seconds. Specific capacitance, energy density and power density are calculated for current values of 1, 2, 3, 4, 5 and 10 amps.

Advantageously, the above synthesis method, elemental composition and derived unique structure help to secure improved specific capacitance and electrochemical reaction of heterostructured SmCoO ₃ /rGO material.

Additional advantages are the rGO-decorated SmCoO ₃ material that promotes molecular absorption, creates more surface sites at the electrode-electrolyte interface for battery-type Faraday reactions, improves ion transport, and provides greater efficiency in supercapacitor applications. in the heterogeneous structure of

More preferably, the improved electrochemical performance of the hybrid two-electrode SmCoO ₃ /rGO//AC supercapacitor assembly is a high specific capacitance of 166 F/g at 1 A/g, 52 Wh/g from the CV and GCD curves. It represents an energy density of kg and a power density of 752 W/Kg. Moreover, the hybrid two-electrode SmCoO ₃ /rGO//AC supercapacitor assembly possesses a characteristic of 74.28% capacity at 15,000 charge-discharge cycles.

The description of the specific embodiments set forth herein is sufficient to enable others to adapt and/or improve the specific embodiments for various applications without departing from the general concept by applying their present knowledge. With respect to the examples, general features are disclosed, and therefore, such modifications and improvements are intended to fall within the scope and meaning of equivalents of the disclosed embodiments, and to be understood within the scope and meaning of the disclosed embodiments. It is to be understood that the phraseology or terminology used herein is for the purpose of description and not limitation. Accordingly, although the embodiments herein have been described as preferred embodiments, those skilled in the art to which the present invention pertains can practice the embodiments herein with modifications within the scope and spirit of the described embodiments. It should be understood that there is

Claims (9)

Graphene oxide is prepared through the improved Hummer technology,
Prepare a reduced graphene oxide (rGO) homogeneous solution,
A homogeneous solution of samarium cobalt oxide (SmCoO ₃ ) is synthesized by mixing samarium (III) nitrate, cobalt nitrate hexahydrate and urea,
By dispersing the graphene oxide (rGO) in the samarium cobalt oxide (SmCoO ₃ ) to produce a SmCoO ₃ /rGO homogeneous solution,
forming a SmCoO ₃ /rGO material by maintaining the uniform SmCoO ₃ /rGO solution in an autoclave;
calcining the SmCoO ₃ /rGO material held in the autoclave to form a heterostructured samarium cobalt oxide-decorated reduced graphene oxide (SmCoO ₃ /rGO);
to evaluate the electrochemical properties by characterizing the heterostructured SmCoO ₃ /rGO material, and
A method for fabricating an improved heterostructured SmCoO ₃ /rGO material, wherein the heterostructured SmCoO ₃ /rGO material exhibits improved electrochemical properties.
The improved heterogeneous compound according to claim 1, wherein samarium (III) nitrate, cobalt nitrate hexahydrate and urea are mixed in a ratio of 1:2:8 and dissolved in 80 mL of a mixed solution of deionized water and ethanol. Methods for making structured SmCoO ₃ /rGO materials.
The improved heterogeneous SmCoO ₃ /rGO of claim 1 , wherein a homogeneous solution of reduced graphene oxide (rGO) is prepared by subjecting the graphene oxide to a hydrothermal process at approximately 120° C. for 5 hours. How to make the material.
The method of claim 1, wherein 0.2 g of reduced graphene oxide (rGO) is dispersed in samarium cobalt oxide (SmCoO ₃ ) to prepare a homogeneous solution of the samarium cobalt oxide-decorated reduced graphene oxide (SmCoO ₃ /rGO). A method for preparing an improved heterostructured SmCoO ₃ /rGO material, comprising:
The method of claim 1 , wherein the homogeneous _{SmCoO 3} /rGO solution is maintained in an autoclave at approximately 180° C. for 12 hours.
6. The improved heterostructured SmCoO ₃ according to claim 5, wherein the heterostructured SmCoO ₃ /rGO material is formed by calcining the SmCoO ₃ /rGO material in the autoclave at approximately 400° C. for 3 hours. How to make /rGO material.
The method of claim 1 , wherein the characterization of the heterostructured _{SmCoO 3} /rGO material reveals better electrochemical properties.
The method of claim 1 , wherein the heterostructured SmCoO ₃ /rGO material is used for the fabrication of a hybrid two-electrode SmCoO ₃ /rGO//AC assembly _. .
The electrochemical properties of the hybrid two-electrode SmCoO ₃ /rGO//AC assembly according to claim 8, wherein the high energy density of 52 Wh/Kg at 1 A/g current density, the high power density of 752 W/Kg and A method for preparing an improved heterostructured SmCoO ₃ /rGO material, characterized in that it has a high specific capacitance of 166 F/g, and a capacity of 74.28% for 5000 cycles.

Images