These solar batteries are quite large, are not very effective under diffused light and also cost quite a lot, although prices dropped significantly recently. Scientists all over the world who are actively searching for alternative solar-cell materials noticed the rather promising perovskites not so long ago.
Professor Anvar A. Zakhidov, Deputy Director of the UT Dallas Nano-Tech Institute, a leading expert on alternative energy, and head of initiative research project on “High-Capacity Polymer Tandem Photovoltaics on the Basis of Hybrid Perovskites” at the National University of Science and Technology MISIS (NUST MISIS), Moscow, Russia discusses the amazing properties of these materials and various possibilities they open up for humankind.
Question: Mr. Zakhidov, could you say a few words about perovskites and their discovery?
Anvar Zakhidov: Classic perovskite crystals with the same type of crystal structure as calcium titanate (CaTiO3), known as the perovskite ABX3 structure, were first discovered in 1839 in the Ural region. The mineral was named after Count Leo Perovsky, a Russian collector of minerals.
Scientists later discovered other types of perovskites, including barium titanate, lithium niobate and lanthanides. All perovskites have a similar structure with the ABX3 pattern. This complicated structure features crystal atoms that are intricately bound by ion bonds, but each of the three elements can be replaced.
If we take a new hybrid perovskite on which we are currently working, then one of its elements should be organic molecular ion, and this element should consist of carbon and hydrogen. For example, A denotes the so-called methylamine (CH3NH3), B denotes lead (Pb) and X denotes iodine (I). It is not easy to make a three-element combination because their sizes should be of a certain value, fitting the so called tolerance factor.
Question: How many types of…