Paint and other coatings are often essential for components or products that need to be highly resistant to potential environmental effects, like corrosion or dust buildup. Recently, the paint industry has focused on nanotechnology — especially nanoparticles, or particles of matter that are between 1 and 100 nanometers in diameter. Researchers have begun incorporating nanoparticles and similar materials into new paints to provide additional properties, like greater protection against corrosion.

Some nanoparticles also offer unique benefits that can’t be attained with conventional paints, such as antimicrobial properties. This makes them especially appealing for businesses interested in highly effective product coatings. Here’s how nanoparticles are being used to enhance paints in industrial applications.

1. Nanosilver Powder Gives Paints Antimicrobial Properties

Bacteria and microbe control in hospitals can be a difficult task. The level of cleanliness required to prevent infection and enable day-to-day work means surfaces need to be frequently cleaned and sterilized. This ensures safety for doctors and patients while preventing the spread of disease.

Antimicrobial coatings can make the task of keeping surfaces sterile much simpler since microbes are killed or destroyed on contact.

Researchers are experimenting with the use of nanosilver powder mixed with paint to provide an antimicrobial coating solution to hospitals, health care providers and other organizations that need it.

Silver is a well-documented antimicrobial. It can inhibit crucial cellular functions in microbes and is known to kill bacteria, fungi and even certain viruses. Using pure silver as a coating isn’t typically practical, however, which is why researchers are looking to use nanomaterials and ions instead.

New Techniques for Synthesizing Silver Nanopowder

One new approach to synthesizing silver nanopowder, developed by a team of Indian researchers at the Mumbai-based Bhabha Atomic Research Centre (BARC), uses an environmentally friendly process that minimizes the need for harsh chemicals.

The method also prevents the release of silver nanoparticles into the environment by attaching them to a silica substrate with the use of gum arabic. This is an eco-friendly biopolymer derived from the sap of the acacia tree.

In addition to providing paints with antimicrobial properties, the powder could also be used in waste management or to clean water, according to the researchers.

2. Nanotechnology Prevents Corrosion

Corrosion is a significant issue in the industrial world. Globally, the estimated annual cost of fighting it - including inspecting and replacing parts and protecting against corrosion - is around $2.5 trillion. This is equivalent to 3.4% of the global GDP in 2020, according to research from the National Association of Corrosion Engineers (NACE).

Industrial paints and coatings are essential for reducing the impact of corrosion and extending the lifespan of metal parts. New nanotechnology has helped create alternatives that are highly effective at resisting corrosion.

Fighting Corrosion with Graphene Paints and Coatings

For example, recent research by South Australian chemicals company Sparc Technology has found that graphene has promising anticorrosive properties when mixed into commercially available coatings and paints. Graphene is a super-thin material made from carbon atoms arranged in a lattice-like structure.

To test the power of the coating, researchers applied the graphene coating and a control coating to steel substrates and subjected both to 1,344 hours of salt spray. According to the company, the addition of graphene provided a 62% improvement in scribe creep compared to the control coatings, suggesting significantly improved corrosion resistance.

In the company’s tests, the graphene paints and coatings were applied to smooth, cold-rolled steel. This material is typically considered a challenging substrate for anticorrosive coatings. It possesses a less suitable anchor profile than similar substrates, like abrasive blast-cleaned steel, which coatings typically adhere to more easily. The research team considered the success of the graphene coating to be significant.

Combined with other corrosion management techniques — like temperature control and improved airflow — these paints could provide a valuable asset for businesses.

3. Dust-Repellent Coatings With TiO₂-Based Nanomolecules

Businesses experimenting with commercial applications of TiO₂-based nanocoatings have found that they can be effective at controlling dust and dirt when in an area exposed to UV radiation. One new company has developed a nanoparticle delivery system that can be used to create dust-repellent coatings for solar panels, improving their efficiency and minimizing needed maintenance.

The company behind the tech, Swift Coat, primarily expects the technology to be useful in preventing the soiling of solar panels. Over time, they can become less efficient due to the accumulation of dust, dirt and other debris on the panel surface. On a long enough timescale, soiling can reduce solar panel efficiency by up to 30%.

This can create severe problems for businesses and consumers. Solar panels installed on the roof of a home may not be easily accessible by a homeowner. If they can’t clean the panels or afford a cleaning crew that can do it for them, this loss of efficiency can persist for months.

Businesses with remote solar installations face similar challenges. The labor costs of cleaning solar panels can significantly cut into the savings the company may have secured by adopting a green energy source.

Minimizing the Impact of Dirt on Solar Panels With TiO₂

Swift Coat's approach is to use a unique method of applying titanium dioxide-based nanoparticles to solar panels' surfaces once installed. These particles catalyze UV light to decompose airborne dirt and dust particles, helping to slow or even prevent soiling. In practice, the nanocoating may improve the energy production of a solar panel by 3% each year, all without increasing the cost of manufacturing.

The approach, which is called aerosol impact-driven assembly (AIDA) nanomaterial deposition, involves the acceleration of aerosolized nanoparticles “at sonic speed through a slit-shaped nozzle by a gas flow and attached to a substrate.”

In addition to providing a clear coating that helps to repel dust, this process also allows the applicator to control coating porosity and thickness. This helps reduce reflectivity that can negatively affect the solar panel’s efficiency.

The potential anticorrosive effect of titanium dioxide particles, similar to other nanomaterials like graphene, means the coating could also be used to prevent the corrosion of metal parts in a solar panel assembly.

How Nanomaterials Are Changing the Paint Industry

Nanomaterials can provide paints and coatings with unique characteristics — like antimicrobial, anticorrosive and dust-repellent properties — that can offer benefits to a wide range of industries.

The use of nanomaterials is still mostly experimental, but several early commercial applications have shown how nanotechnology may enable new kinds of industrial paint and coatings. The benefits of adding nanoparticles far outweigh the costs and can lead to longer-lasting, more-efficient end products.