TSU radiophysicist will increase the efficiency of solar cells

26 March 2018

Dmitry Gorn, PhD, a senior researcher at the Faculty of Radiophysics, is working to improve the efficiency of converting solar energy into electrical energy. He is creating a photoconverter based on CdHgTe (cadmium-mercury-tellurium), which will increase the efficiency and reduce the cost of solar cells.

- The main component of solar cells is the photoconverter. The classic solar cell transforms the radiation of a predominantly visible range into electric current. The quality of the element is evaluated by the coefficient of efficiency: it shows how much of the energy of the sun’s radiation that has fallen on the element, has been transformed into electric energy. The achieved efficiency values (on the order of 45%) are far from the theoretical limits (about 60%). This makes it necessary to increase the area of the batteries and expedient to use them in regions with intense solar radiation, - notes Dmitry Gorn.

Currently, mainly silicon is used to create photoconverters. However, it basically converts radiation of a visible range (0.3-0.7 μm). The efficiency of photoconversion sharply decreases when the wavelength of the radiation reaches 1.0 μm, and it turns to almost zero at lengths greater than 1.2 μm.

Dmitry Gorn proposed expanding the spectral range of the device to the infrared region, using barrier structures - a new type of structures based on the CdHgTe material. This material is sensitive in the infrared range and can rearrange the spectral region by changing the composition of the semiconductor junction. In addition, the use of barrier structures will make the production of solar cells cheaper.

- Using this material will bring the characteristics of solar cells closer to the theoretical ones, significantly improving the efficiency of the photoconverter and reducing the cost of solar cells. The area of their effective application will also expand: for example, it will spread to regions where converting solar energy into electrical energy was not expedient because of the low intensity of solar radiation, emphasizes Dmitry Gorn.