A sunny window is a new breakthrough in power-emitting solar concentrator technology

It's no surprise that the sunny days transform any window into a usable power source, and the idea of ​​using quantum dots for the luminescent solar concentrator has turned this idea into reality.

It is a window and also a power source

The luminescent solar concentrator (LSC) is an emerging technology that catches the sun, potentially subverting our ways of thinking about and using energy. A joint team of researchers from the U.S. Department of Energy's Los Alamos National Laboratory and the University of Bicca in Milan, Italy, published in the latest issue of Nature Nanotechnology a report titled "Using Non-Heavy Metal Colloidal Quantum Dots Efficient large-area colorless luminescent solar concentrator "for the title of the research results.

Victor Klimov, chief researcher at Los Alamos National Laboratory, said: "In this new device, part of the transmitted light through the window is absorbed by the nanoparticles (semiconducting quantum dots) scattered over the glass window, And then re-emit human invisible infrared wavelengths, the waves are directed to the solar cells on the edge of the window. "With this design, a nearly transparent window in the sunny sun becomes a generator that can be operated at Hot days provide power for air conditioning, or in the winter to power the water heater in the room.

Neither colorless nor toxic

In April 2014, this collaborative research team theoretically proved that the applied QD devices are not suitable for real-world applications because they are based on the toxic heavy metal cadmium and only absorb a small fraction of the solar energy, which Resulting in limited light harvesting efficiency and dark yellow or red marks on the concentrator.

Describing this emerging research, Francisco University of Pikaciju, professor of physics at the Department of Materials Science, pointed out: "To get this technology out of the lab as quickly as possible and to realize its full potential in sustainable buildings, it is essential to be able to capture the entire Non-toxic solar concentrator. "

So, the researchers updated the method to solve the problem of coloring. Klimov explains: "The new equipment uses a complex composition, commonly referred to as CISeS, including Cu, In, Se and S." Importantly, These particles do not contain any toxic metals.

He emphasized that CISeS's quantum dots provide a uniform solar spectrum coverage, adding windows with neutral tones without any distortion of color. In addition, they emit near-infrared light that is invisible to the human eye and is ideally suited for the most common silicon-based solar cells.

High efficiency, low cost

A key advantage of this result is that it is procedurally comparable to the industrial methods of battery casting used to assemble high-quality polymer windows. In the manufacturing process, the quantum dots need to be encapsulated in a high optical quality transparent polymer matrix. The researchers used a cross-linked poly dodecyl methacrylate, which belongs to the class of acrylic polymers whose long side chains prevent the aggregation of quantum dots and give them a "friendly" environment that allows them to be encapsulated To the polymer while maintaining the quantum dot light emitting efficient characteristics.

Francesco said: "We still have to maintain the key ability to transmit guided light, and there is no absorption loss to compensate for the high optoelectronic efficiency that is compatible with the true window size, and aesthetic considerations are also crucial to the expectations of a new technology. "

Hunt McDaniel, a former postdoctoral fellow at Los Alamos National Laboratory who currently works in the field of quantum dots (founder and president of UbiQD), added: "The rest of the job is to solve the problem of cost reduction, Materials made of quantum dots are much cheaper than previous materials.We used a new class of low-cost, low-risk quantum dots to make a mixture CISeS, overcoming some of the biggest barricades in the commercial deployment of this technology. "

Not only energy-saving, but also environmentally friendly

Sergio Brofvini, principal research fellow at the Italian research team, said: "We demonstrated the feasibility of such a quantum dot solar window technology only a year ago, and in reality it can be transferred in the short to medium term The industry not only allows us to turn the roof into a solar generator but also to the city's overall architectural style, including windows. "

"This is especially important in densely populated urban areas where the roof is too small to collect all the energy the building needs." The team estimated that replacing the skyscraper with a power supply with this technology Glass, such as the New York World Trade Center, which divides 72,000 square meters into 12,000 windows, will likely generate the equivalent of more than 350 apartments.

Brevini said: "This quantum dot light-emitting solar concentrator itself can also save energy, the filtering effect can reduce the air conditioning power needed to reduce the outdoor sun into the house caused by warming.Thus, this technology can be potential Promote the city towards zero-energy environmental goals. "