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2D materials consist of a single or a few layers, each layer being between only one or several atoms thin.

Nano2D Lab at London South Bank University (LSBU) is leading the way in this field, pioneering the utilisation of a Continuous Hydrothermal Flow Synthesis (CHFS) approach that uses water as a reaction medium.

What is Continuous Hydrothermal Flow Synthesis?

CHFS uses high-temperature and high-pressure water as a solvent. The reaction takes place in a bespoke continuous flow reactor, which enables the production of homogeneous and well-controlled particles.

As the solution flows through the reactor, the supercritical - high-pressure and high-temperature conditions induce rapid chemical reactions, leading to the formation of nanoparticles or other desired products.

If you want to understand CHFS further, you can see it

This CHFS process is rapid and sustainable and can generate diverse and unique opportunities to design and deliver (via a target-oriented approach) 2D materials with new or enhanced characteristics, and even unexpected new phenomena.

The CHFS approach offers a variety of instant controls (temperature, pressure, residence time, reactant concentration) that allow for a high degree of tailoring/functionalisation of the 2D materials in their design to be fit for purpose.

LSBU are excited by the huge advantages this process presents. Compared to other 2D material manufacturing processes:

• It doesn’t utilise a complex or lengthy process - in fact it is continuous and cyclable

• It is not explosive and limits the use of harmful/toxic chemicals
• It reduces the synthetic process time from hours to seconds and is readily scalable.

What have Nano2D developed?

The Nano2D Lab team has successfully developed hydrothermal fragmentation of graphene sheets to produce water-soluble 0D graphene quantum dots (GQDs) and synthesis of “artificial atoms” derived from biomass 0D materials are less than 10 nanometres and have with excellent, tunable, optical properties.

QDs are incredibly small fragments of graphene arranged in a hexagonal lattice giving them an incredibly strong structure with a very large surface area in a small space. You can learn more about why hexagons are the best-agon via this video: https://youtu.be/thOifuHs6eY

These dots exhibit unique electronic, optical, and magnetic properties that make them suitable for various applications in fields such as electronics, biomedicine, energy storage, and environmental remediation.

CQDs are great for:

• Sensing: GQDs can be used as biosensors to detect specific molecules in biological systems. This puts them at the cutting edge of med-tech. Their small size, high surface area and optical properties make them attractive for sensing applications.
• Imaging: CQDs can be used as contrast agents for bioimaging. They exhibit strong fluorescence properties, making them useful for fluorescence imaging and diagnostics.

• Energy storage: GQDs can be used as electrodes in batteries and supercapacitors. Their high surface area and excellent conductivity make them promising candidates for energy storage applications.
• Catalysis: CQDs can be used as catalysts for a variety of chemical reactions. Their unique electronic properties and high surface area make them efficient catalysts for energy conversion and environmental remediation.

The Nano2D Lab team have taken advantage of this catalyst property to convert CO2 into valuable products, combine metallic Ag (silver) with graphene to give Ag-graphene - this has superior antibacterial properties to Ag and in selected cases outperforms antibiotics - and even 3D printed CHFS-synthesised graphene nanocomposite materials to act as a catalyst in CO2 utilisation reactions.  

So, what’s the big deal?

CQDs can be synthesized by a variety of methods, including chemical exfoliation, hydrothermal synthesis, and laser ablation.

With CQDs providing so many incredible opportunities for research, innovation and development, Nabo2D Lab’s successful development of the CHFS methodology offers significant advantages over the more conventional synthetic routes including batch hydrothermal processes.

It is universally accepted as offering greener, more sustainable process chemistry and its use has been given further impetus by a life-cycle assessment concluding that CHFS offers a substantial degree of reduction in the overall life-cycle environmental impact.

Nano2D Lab’s approach to making 2D derivatives employs a clean, rapid and novel technology that will enable a step change in the cost, performance and durability of nanomaterials. This revolution will have cascading effects throughout industry, academia, and wider society by providing access to next generation high tech components, a range of research areas surrounding these applications, and solutions to societal, economic, and environmental problems.

Our huge congratulations to Dr Suella Kellici and the Nano2D Lab team for their integral work toward the technology of the future.

To find out more about the work they do and explore the opportunities available to businesses, you can connect with us here.

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