Solar Paint, A Scientific Breakthrough
House paint has the capability to be more than just coatings on bricks — in the future, it could also be used as a collecting agent to absorb the energy from the sun and transform it into electricity. This may not be vastly far off, as it’s already an active field of research due to solar paints’ commercial viability, ease of scalability, and cost-effectiveness. Solar paint could become widely available by as soon as 2022!
What is it?
Solar paint essentially attracts molecules of water and cleaves them to create hydrogen to generate electricity. It works like a conventional photovoltaic cell, taking energy from the sun and creating electricity, but is made up of thin-film solar panels in a liquid form. The paint comprises tiny luminescent molecules suspended within a flexible and sprayable liquid, which absorbs light and moisture.
The way the paint can do this is because of the titanium dioxide inside, a crystalline pigment that has an exceptional ability to absorb sunlight and is one of the most promising materials within photovoltaics. It is used in most paints already and is sometimes called “the perfect white”.
This titanium dioxide is paired with synthetic molybdenum disulfide, a latter compound with extraordinary electronic and photoelectronic properties that allows for sustainable solar-to-hydrogen conversion under visible light irradiation. The molybdenum disulfide takes the energy from the titanium dioxide, pulls molecules of water from the air from dew, rainfall, the atmosphere, etc, and splits them into hydrogen and oxygen particles. The oxygen and hydrogen is released into the air, and this hydrogen is used to produce clean energy for powering cells.
Colloidal Quantum Dot Solar Paint
Quantum dot solar cells have been a breakthrough within solar energy because of their significant ability to boost the efficiency of rate absorption to electricity produced. However, these generally take a few days to prepare. Now with a one coat quantum dot solar paint, this can be achieved in under an hour. Although the current efficiency of quantum dot paint is no where up to par with its counterpart in solar cell form (around 8%), this is still a very exciting finding and could end up being 11% more efficient than traditional panels. This would be a simple, cheap, and effective way of producing solar paint!
Quantum dot solar paint is a yellow or brown paste that utilizes semiconductor nanocrystals that emit light when struck with a UV beam. Because of their nano size, when a thin layer of dots is taken, the majority of incident visible sunlight can be captured. Their ability to emit colours is taken advantage of by being used as a replacement for conventional dyes to achieve ideal optical and electronic properties. You can actually alter the light absorption spectrum of the quantum dots by changing their size!
Colloidal quantum dots have been proven so far to be the most effective form of quantum dots for solar paint, which glow in vibrant and distinct colours and are dispersible in solvents. These quantum dots can therefore be mixed with cadmium sulfide, cadmium selenide, or titanium dioxide particles, and a paint is produced.
Barriers
The main barrier with solar paint as of right now is its efficiency, which is generally between 3% and 11%. That means if a 7% efficient solar paint was taken, only 7% of the available energy could be used. This will have to be overcome and at a minimum surpass 10% efficiency if solar paint is going to become commercially viable.
Furthermore, right now, solar paint doesn’t have too long of a shelf life, which is what scientists are trying to achieve with different compositions. Stability is currently at its best when the paint is stored in the dark. There’s also the issue of titanium dioxide sources decreasing over time, especially if solar paint goes widespread. Alternatives and other formulations will need to be found to maintain this as a long-term product.
Lastly, utilizing hydrogen regarding capture and storage is also somewhat of a difficult situation. Unless meticulously engineered, this can be a challenge. The hydrogen needs to be compressed and stored properly and cannot mix with the oxygen, otherwise there could be a harmful explosion.
The Future of Solar Paint
Solar paint could have some pretty wild implications because it is so much easier and cheaper to install than regular solar panels. The process of installation can be done in minimal amounts of time, and a lot of it can even be done by a homeowner with a spray gun (no previous construction knowledge needed!). Additionally, due to its lightness, it can pretty much be applied to any surface of varying shapes and sizes, like plastics, fabrics, fences, sheds, mailboxes, and the list goes on and on! Transparent solar films can even be explored for more efficient automobiles, as they can be placed on windows of vehicles and used to help charge the car’s battery.
Solar paint would be suitable in a range of climates, as any place with water vapor in the air can produce fuel, even if scarce— which is especially ideal for areas that don’t get enough sunlight to justify the need for solar panels. It could be very useful in developing countries, and could technically mean solar farms could be built in deserts!
Of course, there’s also the exceptional environmental impacts this would have, as solar paint would permit a self sustained home running on natural resources instead of fossil fuels. Furthermore, self sustained homes are less likely to face power outages because you’re using your own power source!
Lastly, solar paint is a more aesthetic decision than solar panels. Because solar panels are bulkier and clearly stand out, some people don’t want them on their houses. Solar paint offers a simple, attractive, and non-obtrusive technology.
Conclusion
Solar paint is still fairly new, but the solar industry is progressive and soon enough solar paint could be transforming the ways in which we receive our energy! Let’s do a quick overview of what we’ve learned in this article.
- Solar paint works by using titanium dioxide and synthetic molybdenum disulfide to pull water molecules from the air, split them into their oxygen and hydrogen components, and use the hydrogen to produce clean energy
- Quantum dot solar paint uses colloidal quantum dots (semiconductor nanocrystals) to colour the paint instead of dyes, while also boosting efficiency
- The main four hurdles of solar paint are efficiency, shelf life, titanium dioxide dwindling over time, and the challenges of working with hydrogen
- Solar paint could have mind-blowing applications, from being used to paint electronic devices to windows to cars to roofs
- Solar paint would be cheap and easy to install, and could be used on a variety of different surfaces to generate electricity!
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