Why Do Solar Cells Lose Energy: Ihor Zharchenko Earns His PhD

Ihor Zharchenko, a physicist at the FTMC Laboratory of Electronic Processes, has been awarded a PhD. On 8 May, he defended his dissertation entitled “Direct Impact of Hot Carriers on Photovoltaics” (academic supervisor: Prof. Dr Jonas Gradauskas).

Solar energy is becoming more important every year, and improving solar cell efficiency is essential for cheaper and cleaner energy. Ihor’s work helps to better understand why solar cells lose part of their energy and how these losses could be reduced in the near future. The results may also inspire creation of fast and convenient to use infrared and visible laser light detectors.

More specifically, the Ukrainian scientist’s dissertation studies how hot carriers behave inside solar cells and other semiconductor devices. These hot carriers are electrons and holes that have extra energy, gained by after absorbing light.

“I investigated how they influence the electric current and efficiency of solar cells, and how this effect can also be used for developing novel concept light sensors.

I showed that hot carriers appear in solar cells under various conditions of light excitation and can directly affect the generated photocurrent. The research demonstrated that hot carriers may cause additional energy losses in ordinary solar cells.

I also developed a method to estimate hot carrier temperature from electrical measurements and proposed a new type of laser light sensor based on hot carrier effects,” explains Ihor.

We congratulate our colleague and wish him every success in contributing to the further development of solar cells!

You can read the full dissertation by following this link.

Source: FTMC