BIO-SYNTHESIS OF EUROPIUM DOPED CERIUM OXIDE/GRAPHENE OXIDE NANOCOMPOSITES USING KIWI PEEL EXTRACT

Abstract

ABSTRACT “BIO-SYNTHESIS OF EUROPIUM DOPED CERIUM OXIDE/GRAPHENE OXIDE NANOCOMPOSITES USING KIWI PEEL EXTRACT” The present invention relates to a green synthesis method for producing Europium-doped Cerium Oxide/Graphene Oxide (Eu-CeO₂/GO) nanocomposites using kiwi peel extract as a natural reducing and stabilizing agent. The process involves preparing an aqueous solution of graphene oxide (GO) and adding cerium and europium nitrate salts under constant stirring. Kiwi peel extract, is then introduced into the solution to facilitate the reduction of metal ions and the nucleation of Eu-doped CeO₂ nanoparticles on the GO surface. After synthesis, the nanocomposite is separated, washed, and dried. The resulting Eu-doped CeO₂/GO nanocomposites exhibit enhanced luminescence, catalytic properties, and biocompatibility, making them suitable for diverse applications, including catalysis, bioimaging, energy storage, sensors, and optoelectronics. This sustainable approach reduces environmental impact by utilizing agricultural waste, minimizes the use of toxic chemicals, and promotes eco-friendly nanoparticle synthesis.

Specification

Description:BIO-SYNTHESIS OF EUROPIUM DOPED CERIUM OXIDE/GRAPHENE OXIDE NANOCOMPOSITES USING KIWI PEEL EXTRACT
FIELD OF THE INVENTION
This invention relates to the field of nanomaterials, specifically to the biosynthesis of metal oxide nanocomposites. More particularly, it relates to the synthesis of europium-doped cerium oxide/graphene oxide nanocomposites using an environmentally friendly and cost-effective method employing kiwi peel extract. The invention also encompasses the application of these nanocomposites in various fields, including but not limited to catalysis, biomedicine, and energy storage.
BACKGROUND OF THE INVENTION
Cerium Oxide (CeO₂) nanoparticles and Graphene Oxide (GO) are gaining significant attention due to their unique properties, making them valuable for various applications such as catalysis, sensors, bioimaging, energy storage, and optoelectronics. CeO₂ nanoparticles are well-known for their excellent catalytic activity, redox properties, and UV absorption capabilities. Meanwhile, GO, with its high surface area, electrical conductivity, and mechanical strength, offers an ideal platform for creating advanced nanocomposites. The combination of these two materials into a nanocomposite further enhances their performance. Additionally, doping CeO₂ with rare earth elements like Europium (Eu³⁺) introduces structural defects that improve optical, magnetic, and catalytic properties, making it even more useful for advanced technological applications.
Despite their potential, the synthesis of CeO₂/GO and Eu-doped nanocomposites often involves complex procedures, harsh chemicals, and high energy consumption. Conventional methods such as hydrothermal synthesis, microwave-assisted processes, and chemical reduction require precise conditions and multiple steps, making them time-consuming and labor-intensive. These processes also rely on toxic reducing agents, such as sodium borohydride and hydrazine, posing safety risks and generating hazardous waste. Furthermore, the high temperatures and pressures involved increase energy consumption, making these synthesis methods economically unsustainable in the long run. In biomedical applications, nanomaterials synthesized through these traditional routes can exhibit cytotoxicity, limiting their safety for human use.
The Need for Green, Sustainable Synthesis
There is a growing need for sustainable and eco-friendly synthesis protocols that reduce environmental impact while maintaining high material quality. Green chemistry principles offer a way to achieve this by minimizing toxic substances, lowering energy consumption, and reducing chemical waste. Using natural materials like plant extracts as precursors can replace synthetic chemicals, promoting sustainable practices. In this context, agricultural waste, such as kiwi fruit peel, provides an excellent alternative. Rich in bioactive compounds like polyphenols, flavonoids, terpenoids, and amino acids, kiwi peel extract acts as a natural reducing and stabilizing agent. This not only eliminates the need for toxic chemicals but also promotes the recycling of waste from the food industry.
OBJECT OF THE INVENTION
The principal object of the invention is to develop a green synthesis method for producing Europium-doped Cerium Oxide/Graphene Oxide (Eu-CeO₂/GO) nanocomposites.
Another object of the present invention is to develop a green synthesis method for producing Europium-doped Cerium Oxide/Graphene Oxide (Eu-CeO₂/GO) nanocomposites which eliminates the need for toxic chemicals but also promotes the recycling of waste from the food industry.
SUMMARY OF THE INVENTION
The invention proposes a green synthesis route for Europium-doped Cerium Oxide/Graphene Oxide (Eu-CeO₂/GO) nanocomposites using kiwi fruit peel extract.
In an aspect of the present invention, a green biosynthesis method for producing Europium-doped Cerium Oxide/Graphene Oxide (Eu-CeO₂/GO) nanocomposites is disclosed wherein, the method comprises steps of Preparing an aqueous solution of graphene oxide (GO);Adding cerium nitrate and europium nitrate to the GO solution under constant stirring; Introducing a predetermined quantity of kiwi peel extract into the mixture; Stirring the mixture at a controlled temperature and pH for a specific period to facilitate the reduction of metal ions and the nucleation of Eu-doped CeO₂ nanoparticles on the GO surface; Separating, washing, and drying the resulting Eu-doped CeO₂/GO nanocomposite.
BRIEF DESCRIPTION OF DRAWING
Figure 1: Illustrates Schematic Diagram of a green synthesis method
DETAILED DESCRIPTION OF THE INVENTION
While the present invention is described herein by way of example using embodiments and illustrative drawings, those skilled in the art will recognize that the invention is not limited to the embodiments of drawing or drawings described and are not intended to represent the scale of the various components. Further, some components that may form a part of the invention may not be illustrated in certain figures, for ease of illustration, and such omissions do not limit the embodiments outlined in any way. It should be understood that the drawings and the detailed description thereto are not intended to limit the invention to the particular form disclosed, but on the contrary, the invention is to cover all modifications, equivalents, and alternatives falling within the scope of the present invention as defined by the appended claim.
In this disclosure, whenever a composition or an element or a group of elements is preceded with the transitional phrase "comprising", it is understood that we also contemplate the same composition, element, or group of elements with transitional phrases "consisting of", "consisting", "selected from the group of consisting of, "including", or "is" preceding the recitation of the composition, element or group of elements and vice versa.
The invention proposes a green synthesis route for Europium-doped Cerium Oxide/Graphene Oxide (Eu-CeO₂/GO) nanocomposites using kiwi fruit peel extract.
In an aspect of the present invention, a green biosynthesis method for producing Europium-doped Cerium Oxide/Graphene Oxide (Eu-CeO₂/GO) nanocomposites is disclosed wherein, the method comprises steps of Preparing an aqueous solution of graphene oxide (GO);Adding cerium nitrate and europium nitrate to the GO solution under constant stirring;Introducing a predetermined quantity of kiwi peel extract into the mixture;Stirring the mixture at a controlled temperature and pH for a specific period to facilitate the reduction of metal ions and the nucleation of Eu-doped CeO₂ nanoparticles on the GO surface;Separating, washing, and drying the resulting Eu-doped CeO₂/GO nanocomposite.
In an embodiment of the aspect disclosed, the green synthesis method, wherein the kiwi peel extract is obtained from agricultural waste.
In another embodiment of the aspect disclosed, the green synthesis method, wherein the concentration of europium nitrate is varied to control the doping level of the nanocomposite.
In yet another embodiment of the aspect disclosed, the green synthesis method, wherein the heating step is performed at a temperature between 60-100°C.
The synthesis process begins with the preparation of an aqueous solution of graphene oxide (GO). GO, an oxidized derivative of graphene, contains numerous oxygen functional groups such as hydroxyl, carboxyl, and epoxy groups, making it highly dispersible in water. These functional groups not only improve the solubility of GO but also act as anchor points for the deposition of nanoparticles, which is crucial for the formation of a stable nanocomposite. Achieving a uniform dispersion of GO through stirring ensures that the GO sheets remain well-separated, providing an extensive surface area for the subsequent growth of nanoparticles. The process begins by preparing an aqueous solution containing cerium and europium salts, typically using precursors like cerium nitrate hexahydrate and europium chloride or nitrate. Graphene oxide (GO) is also dispersed in the solution to prevent nanoparticle aggregation and enhance the electrical, mechanical, and redox properties of the final nanocomposite. GO offers a large surface area with functional groups that facilitate the attachment of nanoparticles, making it an ideal substrate for nanocomposite fabrication.
Once the GO solution is ready, cerium nitrate and europium nitrate-used as metal precursors-are added under continuous stirring to ensure uniform mixing. Cerium nitrate provides the cerium ions (Ce⁴⁺) needed to form cerium oxide (CeO₂) nanoparticles, while europium nitrate introduces europium ions (Eu³⁺) into the matrix. The Europium doping creates structural defects within the cerium oxide lattice, which enhances the material's luminescence and catalytic activity. Constant stirring ensures the even distribution of metal ions throughout the solution, which is essential for producing a homogeneous nanocomposite.
A specific amount of kiwi peel extract is then introduced into the mixture. Kiwi peel contains bioactive compounds such as polyphenols, flavonoids, and organic acids, which function as natural reducing and stabilizing agents. The controlled addition of the extract ensures that these compounds are available in the right concentration to reduce the Ce⁴⁺ and Eu³⁺ ions into their respective oxide forms. Stirring the mixture at a controlled temperature and pH helps maintain favorable conditions for the reduction reactions to proceed efficiently. During this process, the metal ions are reduced, and nucleation occurs-meaning that small clusters of Eu-doped CeO₂ nanoparticles begin to form on the GO surface. The kiwi peel extract acts as a bioreducing agent. The bioactive molecules within the extract reduce cerium (Ce⁴⁺) and europium (Eu³⁺) ions, initiating nucleation and facilitating the growth of CeO₂ nanoparticles doped with Europium. During this reduction and nucleation process, the nanoparticles deposit uniformly onto the GO surface, forming the desired Eu-doped CeO₂/GO nanocomposite. The kiwi peel extract also acts as a stabilizing agent, preventing the nanoparticles from aggregating and enhancing their biocompatibility, which is essential for applications in biomedical fields.
The bioactive compounds from the kiwi peel not only reduce the metal ions but also promote the nucleation and growth of CeO₂ nanoparticles doped with europium ions. The controlled conditions of temperature, pH, and stirring ensure that the nanoparticles grow uniformly and adhere to the GO sheets. The GO surface prevents the aggregation of nanoparticles by providing a stable platform for their deposition. This step is critical, as it directly influences the size, shape, and morphology of the final nanocomposite, which are important factors for its optical, electrical, and catalytic properties.
Once the reduction and nanoparticle formation are complete, the resulting Eu-doped CeO₂/GO nanocomposite is separated from the solution. Techniques such as centrifugation or filtration can be used to isolate the nanocomposite. The separated nanocomposite is then washed multiple times with water or ethanol to remove any unreacted precursors or residual extract. This ensures that the final product is free from impurities, which could affect its performance in applications. After washing, the nanocomposite is dried at a specific temperature to remove any remaining moisture.
The concentration of the metal precursors, the amount of kiwi peel extract, the reaction temperature, pH, and stirring time are critical parameters that can be optimized to control the final properties of the nanocomposite. For instance, adjusting the reaction temperature can influence the size and crystallinity of the nanoparticles, while pH adjustments can affect the reduction rate and stability of the particles. Similarly, optimizing the reaction time ensures that the nanoparticles grow to the desired size without agglomerating. These parameters are fine-tuned to achieve the ideal size, morphology, and functionality of the Eu-doped CeO₂/GO nanocomposite, making it suitable for applications such as catalysis, bioimaging, energy storage, and sensors.
This biosynthesis method is simple, energy-efficient, and environmentally friendly compared to traditional techniques. It eliminates the need for toxic chemical reducing agents like hydrazine or sodium borohydride, ensuring the process is safer for researchers and the environment. The use of kiwi peel extract not only reduces the environmental impact by repurposing agricultural waste but also lowers production costs by utilizing inexpensive and renewable resources. This sustainable synthesis route offers a scalable solution for producing high-performance Eu-doped CeO₂/GO nanocomposites, making them suitable for a wide range of applications, including catalysis, sensors, bioimaging, energy storage, and optoelectronics.
The synthesis is carried out through a sol-gel process, where the mixture undergoes gelation, drying, and calcination at moderate temperatures. This environmentally friendly process eliminates the need for toxic reducing agents and organic solvents, ensuring a safer and more sustainable production method. Additionally, it requires lower energy input compared to traditional methods, making it economically viable and scalable for industrial applications.
This invention offers a novel and eco-friendly approach to synthesizing Europium-doped Cerium Oxide/Graphene Oxide (Eu-CeO₂/GO) nanocomposites by utilizing kiwi fruit peel extract as a natural reducing and stabilizing agent. The method replaces conventional toxic chemical processes with a green biosynthesis technique, contributing to sustainable manufacturing. The synthesis leverages the bioactive compounds present in kiwi peel extract, such as polyphenols, flavonoids, and organic acids, which play crucial roles in reducing metal ions and stabilizing nanoparticles. , Claims:We claim;
1. A green synthesis method for producing Europium-doped Cerium Oxide/Graphene Oxide (Eu-CeO₂/GO) nanocomposites, comprising;
a) Preparing an aqueous solution of graphene oxide (GO);
b) Adding cerium nitrate and europium nitrate to the GO solution under constant stirring;
c) Introducing a predetermined quantity of kiwi peel extract into the mixture;
d) Stirring the mixture at a controlled temperature and pH for a specific period to facilitate the reduction of metal ions and the nucleation of Eu-doped CeO₂ nanoparticles on the GO surface;
e) Separating, washing, and drying the resulting Eu-doped CeO₂/GO nanocomposite.
2. The green synthesis method as claimed in claim 1, wherein the kiwi peel extract is obtained from agricultural waste.
3. The green synthesis method as claimed in claim 1 wherein; the concentration of europium nitrate is varied to control the doping level of the nanocomposite.
4. The green synthesis method as claimed in claim 1 wherein; the heating step is performed at a temperature between 60-100°C.

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