Graphene nanoparticles (GNPs) are microscopic particles formed by graphene, which is composed of one layer of carbon atoms stacked in a honeycomb lattice in two dimensions. A remarkably mechanical, electrical and thermal material, graphene has become one of the most promising nanomaterials around. Graphene at the nano-scale becomes such that the nanoparticles of graphene are distinct from bulk graphene. Those attributes make GNPs very desirable in all sorts of applications, from electronics to medicine, energy storage and environment restoration.
Graphene nanoparticles usually are defined as particles of size ranging from a few nanometers to around 100 nanometers. These nanoparticles' small size and high surface area make them highly reactive and versatile in industries and sciences. These particles are generally created through exfoliation of graphite or chemical vapor deposition methods and can be used to make them better for certain applications.
Fig.1 Structure of graphene nanoparticle. (Srivastava, Isha, et al., 2024)
There are a number of important characteristics that the graphene nanoparticles have that are very beneficial in many industries. These include:
High Surface Area: The top feature of graphene nanoparticles is the huge surface area. GNPs are also very large in surface-to-volume ratio, which means they're better at binding to other materials because they're nanoscale. This is especially relevant in fields such as energy storage, catalysis, and drug delivery, where surface interactions matter for performance.
Mechanical Strength: Graphene has outstanding mechanical properties and when stripped to the nanoscale, these characteristics are retained, only now more elastic. GNPs are tensile stronger than steel and are light weight, so ideal for composites, coatings, and building structures.
Electrical and Thermal Conductivity: Nanoparticles of graphene keep the electrical and thermal conductivity of bulk graphene high. They facilitate electron transfer with a high speed, and they're often used in electronic components, sensors and conductive films. These attributes also lend GNPs a perfect place for energy storage devices like batteries and supercapacitors.
Chemical Reactivity and Functionalization: Because of their surface area and functional groups present, graphene nanoparticles are extremely reactive. That makes it easy to tinker with their surface chemistry, to functionalize them with other molecules or atoms. This versatility of modifying their surface makes the application possibilities infinite, from specialized drug delivery to environmental sensing.
Optical Properties: Graphene nanoparticles have a distinct optical character too. They react with light differently to bulk graphene at the nano scale, and so are useful for photodetectors, light detectors and other optical instruments.
The synthesis of graphene nanoparticles is a critical step in determining their properties and applications. Several methods have been developed to produce GNPs, each with its advantages and challenges. The most commonly used synthesis techniques include:
Exfoliation of Graphite: Exfoliation is one of the most straightforward methods for producing graphene nanoparticles. This technique involves mechanically or chemically separating graphene layers from bulk graphite. Chemical exfoliation methods often use strong acids or solvents to separate the layers, while mechanical exfoliation techniques utilize ultrasound or shear forces. However, controlling the size and dispersion of the resulting graphene nanoparticles can be challenging.
Chemical Vapor Deposition (CVD): CVD is a widely used method for synthesizing high-quality graphene and graphene nanoparticles. In this process, a carbon-containing gas (such as methane) is decomposed at high temperatures in the presence of a catalyst. The carbon atoms are then deposited onto a substrate, forming a graphene layer. By controlling the temperature, pressure, and flow rate of gases, the size of the graphene nanoparticles can be precisely controlled. CVD-produced GNPs often have fewer defects and higher quality than those produced by exfoliation.
Reduction of Graphene Oxide: Graphene oxide (GO) is a precursor to graphene and can be reduced chemically or thermally to produce graphene nanoparticles. Reduction processes involve the removal of oxygen-containing functional groups (such as hydroxyl, epoxide, and carboxyl groups) from the GO sheets. This method allows for the easy production of GNPs with varying levels of reduction, but it may also introduce defects in the structure.
Solvothermal and Hydrothermal Methods: These methods involve the use of high-pressure, high-temperature conditions to facilitate the conversion of carbon-based precursors (such as sugars or carbonates) into graphene nanoparticles. These methods can be tuned to produce GNPs with specific properties, but they typically require specialized equipment and are less scalable than other techniques.
Laser Ablation: In this method, a laser is used to vaporize a carbon target, which then condenses to form graphene nanoparticles. This process can be used to create highly pure graphene with few defects, but it is often limited in scalability and can be expensive.
Graphene nanoparticles possess a range of advantages that make them suitable for diverse applications:
Enhanced Performance: Due to their high surface area, conductivity, and mechanical strength, GNPs can significantly improve the performance of composite materials, energy storage devices, and sensors. For instance, adding GNPs to lithium-ion batteries can increase their energy density and cycle life.
Versatility: GNPs can be functionalized to suit specific needs, making them adaptable to a variety of fields. This versatility allows for their use in industries as diverse as medicine, electronics, and environmental remediation.
Biocompatibility: Graphene nanoparticles are relatively biocompatible compared to other nanomaterials, making them suitable for medical applications such as drug delivery, bioimaging, and cancer therapy. Additionally, their large surface area allows for efficient attachment of biomolecules, enabling targeted therapies.
Sustainability: Graphene is derived from carbon, one of the most abundant elements on Earth. The synthesis of graphene nanoparticles from renewable sources, such as biomass, further enhances the sustainability of the material. This makes GNPs an attractive option for eco-friendly technologies.
Cost-Effectiveness: As the methods for producing graphene nanoparticles become more refined and scalable, the cost of production is expected to decrease. This would make GNPs accessible for commercial applications, driving innovation in industries like electronics, energy, and environmental protection.
The unique properties of graphene nanoparticles have led to their incorporation into a wide variety of applications:
Energy Storage and Conversion: GNPs are extensively used in the development of advanced energy storage devices, such as supercapacitors and lithium-ion batteries. Their high surface area and electrical conductivity make them ideal for improving the performance and capacity of these devices. Furthermore, GNPs are also being explored for use in solar cells and fuel cells, where they can enhance energy conversion efficiency.
Electronics and Sensors: Graphene nanoparticles are used in the development of flexible electronics, conductive inks, and sensors. Their electrical conductivity and mechanical strength make them suitable for wearable devices, touchscreens, and other electronic components. Additionally, their high surface area allows them to function as sensitive sensors for detecting gases, chemicals, or biological markers.
Biomedical Applications: In medicine, graphene nanoparticles are being researched for use in drug delivery systems, cancer therapy, and diagnostic imaging. Due to their biocompatibility and ability to be functionalized with specific molecules, GNPs can be used to deliver drugs or genes directly to targeted cells, minimizing side effects and improving treatment outcomes.
Environmental Remediation: GNPs can be employed for environmental cleanup, particularly in water purification. Their high surface area allows them to adsorb pollutants such as heavy metals, oils, and dyes from water, making them useful for water treatment and pollution control.
Composite Materials: In construction and manufacturing, GNPs are added to polymers, ceramics, and metals to enhance their strength, thermal conductivity, and electrical properties. These advanced composite materials are used in aerospace, automotive, and construction industries to produce lighter, stronger, and more efficient components.
Fig.2 Comprehensive application of graphene nanoparticles. (Syama, S., and P. V. Mohanan., 2019)
BOC Sciences offers a wide range of graphene nanoparticle products as well as customized products in different types to meet a variety of research and application needs. Below is the list of products we can provide, if you have more needs, please contact us to customize the synthesis of your graphene nanoparticles.
| Product Type | Price |
| Functional Graphene Nanoparticles | Inquiry |
| Graphene Oxide Nanoparticles | Inquiry |
| Magnetic Graphene Nanoparticles | Inquiry |
| 3D Graphene Oxide Nanoparticles | Inquiry |
Graphene oxide nanoparticles are nanostructures derived from oxidized graphene, possessing unique electronic, thermal, and mechanical properties suitable for biomedical and sensing applications.
Graphene nanoparticles are made by exfoliating graphite through chemical, thermal, or mechanical methods, yielding nanoscale sheets with distinct properties.
Graphene oxide nanoparticles are synthesized via Hummers' method, oxidizing graphite in acidic solutions and exfoliating it into oxidized nanosheets.
Graphene oxide nanoparticles are used in drug delivery, biosensors, water purification, and energy storage due to their high surface area and functional groups.
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