A group of researchers from St Petersburg University and the Free University of Berlin have developed a photoactive nanocoating that wipes out microorganisms on the surfaces of solar panels.  This will make it possible to extend the service life and increase the efficiency of these devices, which provide an alternative source of energy.  This research project is but one of the results of a 50-year partnership between the two universities. 

In honor of this milestone anniversary, the two universities have inaugurated the first-ever scholarship programme for postdoctoral fellows. 

Today, the total area of all solar panels in the world amounts to more than 4,000 square kilometers.  Experts believe that by 2050 they will have become the primary source of electrical energy.  Nonetheless, scientists have yet to solve a host of problems in the field of solar energy, one of them being the formation of  biofilms that come from microorganisms and the traces of their vital activities, and also from dust, dirt and pollen, on the surfaces of solar panels.  Such biofouling leads to a loss of energy and difficulties in the operation of solar cells.

The international group of researchers from St Petersburg University and the Free University of  Berlin studied the composition of the micro-foulers on the surfaces of solar panels and created a unique photoactive nanocoating based on nanoparticles of titanium oxide. 

“Our coatings are composed of nanoparticles of titanium oxide, which absorb short waves of sunlight.  As a result, active oxidant radicals are formed, and they burn off the microorganisms.  At the same time, the nanoparticles themselves remain on the surface of the solar cells and continue to contend with the biofilms if and when they reappear.  So, it is sufficient to cover the surfaces of the solar panels one time.”  Detlef  Bahnemann, leader of the Russian group of researchers and head of the St Petersburg University Laboratory of  Photoactive Nanocomposite Materials, which is supported by a mega-grant from the Russian government.

Photoactive nanocoatings not only effectively destroy biofilms, but they also enhance the performance of solar cells by 1-2 percent.  However, the primary benefit of this coating, when compared with alternative methods, is its environmental friendliness – under the influence of the titanium oxide nanoparticles, decomposition products, such as carbon-dioxide gas and water, are formed, and they break down the microorganisms. 

The project “Biomineralogical Fouling of Solar Cell Surfaces Leading to a Loss of Solar Conversion Efficiency: Research and Prevention” is being carried out as part of a joint programme of St Petersburg University and the Free University of Berlin that co-finances scientific research.  The two universities, which this year are celebrating fifty years of partnership, actively share their experience in the areas of education and research.

More detailed information about participation in the programme may be found on the site.

One of the most recent joint projects was the first-ever scholarship programme for postdoctoral fellows.  The recipients will not only be given financial support; they will also carry out research under the guidance of scientists from St Petersburg and Berlin and will be able to use the infrastructure of both universities for two years and to work on large-scale international projects.  Aspirants from all subject areas who have either a master’s degree or PhD (or the equivalent) are eligible to apply.