Japanese scientists have developed a new organic photovoltaic film that is waterproof and flexible. These solar cells can be embedded in clothing and these cells will function properly after being soaked in rain or washed in a washing machine.
One of the potential uses of organic photovoltaics is to make wearable electrical devices (devices that can be attached to clothing without the need for batteries). However, it was a difficult step for the researchers to make it waterproof without using additional dimensions, the addition of which would have reduced the flexibility of the film.
According to the latest research published in the journal Nature Communications, a group of scientists have combined the two features to make such devices waterproof without reducing their flexibility.
Photovoltaic films usually consist of multiple dimensions. It has an active component that extracts energy of a specific wavelength from sunlight and uses this energy to separate electrons and ‘electron holes’ at the cathode and anode. Electrons and holes can be recombined with the help of a circuit that produces electricity.
In this study, the researchers deposited the anode layer directly on the active surfaces, which improved the relationship between these dimensions. The scientists used a thermal annealing process in which the film was placed in hot air at 85 degrees Celsius for 24 hours.
The results obtained from the test conducted by the team of scientists are very encouraging. First, scientists immersed the film completely in water for four hours and found that the film was performing 89 percent of its original performance despite being submerged in water. Later, the scientists stretched the film 300 times under water and found that despite the stress, the film’s efficiency remained at 96 percent.
In the final test, they spun the film in a washing machine and the film passed this stage without any difficulty.
This achievement was achieved jointly by scientists from the Raikan Center for Emergent Matter Science, University of Tokyo and Huazhong University in China.
