Japan.. the invention of "invisible" wearable solar cells
Researchers at Tohoku University in Japan have succeeded in making transparent solar cells. These cells are distinguished by their enormous capacity, despite their small size, and you may soon find them installed in the building of your neighborhood!
There has been much talk recently about the possibility of making real use of nuclear energy, but the reality indicates that we will need a long time to be able to do so, unlike other renewable energy sources such as wind energy.
To understand what nuclear energy is, look - certainly not literally - at the sun. This giant ball of flame is located at the center of our solar system, radiating about 173,000 terawatts of solar energy reaching planet Earth.
This amount of energy is 10,000 times more than what our planet needs, so it is no wonder that scientists are seeking to harness solar energy for the benefit of humanity. Working on a large-scale project to harness the sun's energy faces many obstacles, including those related to the solar panels themselves, because they are big, dark and - let's be honest - unsightly.
To get around these hurdles, researchers from Tohoku University found a simple solution. Engineers designed "semi-transparent solar cells," or NISC, that allow 80% of the light to pass through. Theoretically, these cells can be placed on the balcony of the house, on the phone screen, or even implanted under the human skin!
"The idea of creating transparent solar cells has received a lot of attention because of its many advantages that overcome the disadvantages of conventional solar cells," the researchers explained.
"We succeeded in making a semi-transparent solar cell cell, using indium tin oxide (ITO) - one of the most transparent oxides in nature - to build two transparent electrodes, and a single-layer tungsten sulphide to build a photosensitive layer."
An optical image of a solar cell made from a two-dimensional atomic layer
The researchers used the above materials, in addition to a thin layer of tungsten oxide sandwiched between indium tin oxide and tungsten sulfide, to make a solar cell that is considered the first of its kind, because it is far better than ordinary transparent cells.
"Our solar cell has a power conversion factor 1,000 times better than a similar device with a normal indium tin oxide electrode," explained Professor Toshiaki Kato of Tohoku University, who was involved in the study.
For this invention to be useful, it must be manufactured on a large scale to be used within existing solar panels. Fortunately, the team researched this, too.
"A huge power conversion factor can be achieved with a precision instrument, but the overall power of the instrument will be limited by its smallness," Toshiaki says.
To increase the energy produced by the cell, it is not as simple as increasing the size of the cell, as this may lead to a decrease in energy rather than an increase in it. Therefore, it was necessary to come up with a suitable engineering design for manufacturing cells on a larger scale.
The researchers found that the aspect ratio must be less than the critical ratio of approximately 36. By increasing the size of the device and taking into account the optimal sequence of parallel connections, a very high degree of transparency can be obtained, perhaps as high as 78%, with a power output capacity of up to to 420 pW.
"This is the highest amount of energy that can be obtained from a solar cell made of such materials, which heralds the possibility of obtaining semi-transparent solar cells on a manufacturing scale."
Source: iflscience - translation: ibelieveinsci