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The recent discovery of the photovoltaic (PV) effect in indium(i) iodide thin films has attracted considerable attention, as this material can be a feasible environment-friendly alternative to the conventional lead halide perovskites. Previously published computational and spectroscopy data suggested that In I could deliver photovoltaic performances comparable to complex lead iodides; this prediction, however, was not supported by a recent experimental study. To address this contradiction, herein we evaluated systematically the potential of In I as a semiconductor material for photovoltaic applications. The solar cells assembled with In I as a light absorber material demonstrated modest power conversion efficiency of 1%. However, the lateral two-terminal devices showed a rather outstanding photoconductivity effect, which we utilized to fabricate photodetectors demonstrating a competitive performance: photodetectivity approaching 1.4 x 10(3), specific detectivity of 5.0 x 10(11) Jones, and maximum pulse frequency of 93.6 kHz. Similar devices assembled in the vertical geometry delivered much inferior performance. GIWAXS analysis revealed that In I films are strongly textured and grow with the crystallographic b-axis oriented perpendicular to the substrate, which means that the layers composed of interconnected In and I atoms are lying parallel to the substrate. The estimated effective charge carrier lifetimes in lateral and vertical devices (2 ms and 15 ms, respectively) confirmed that their strikingly different performances are due to the structural and electronic anisotropy of In I films. The obtained results reveal the importance of the structural dimensionality of the newly designed semiconductor materials: truly 3D structures are required to match complex lead halides in terms of their optoelectronic properties. On the contrary, materials with lower dimensionality, such as 2D In I, could provide excellent performance in lateral photodetector devices, whereas thei

We describe the synthesis and photodetecting properties of new, low band-gap copolymers: P1 with 5,6-difluoro-2,1,3-benzothiadiazole and P2 with 2,1,3-benzothiadiazole, both containing diketopyrrolopyrrole acceptor units. These compounds have been used for fabrication of single layer, solution processed photodetectors. For this purpose, two blends with fullerene derivative (6,6)-phenyl-C61-butyric acid methyl ester ([60]PCBM): P1: [60]PCBM and P2:[60]PCBM, were prepared and applied as active layers in bulk-heterojunction photodiodes. For near infrared light (810 nm), these photodetectors, in spite of single layer structure, display competitive performance, showing specific detectivity up to 5.10(11) Jones, responsivity up to 0.3 A/W and rise and fall times of the transient signals below 10 mu s., Funding Agencies|Russian Foundation for Basic Research (RFBR) [16-29-06337 ofi_m]; Russian Federal Agency for Scientific Organizations [20089-2014-0036]; National Science Centre (Poland) [UMO-2013/09/B/ST5/03521]; Swedish Foundation for Strategic Research [SE13-0060]

Interactive education is a special form of teaching that provides the best conditions for intellectual growth and success of the students. The management of the interactive education includes formation of clinical situations, role games, resolution of the problems based on analysis of clinical situations. The method of cooperative groups is a part of interactive education. We have introduced the method of cooperative groups as part of the lesson “Final module control № 2” for students of ІV course at the faculty of dentistry in order to improve knowledge consolidation in “Orthodontics”. The conduction of the final module control by such method also enables to assess the student’s knowledge gained during the semester as well as develop clinical approach. The results of interactive technologies using method of cooperative groups at the Department of Pediatric Dentistry demonstrated the increase in students’ motivation to study and revise the topics of final module control, increase in the level of the material awareness, formation of communication skills, the ability to develop the questions, correct the colleagues regarding the issues of treatment or diagnosis, mastering of practical skills and as a result improvement of professional aptitude. Therefore, we can assume that implementation of different technologies of cooperative education is essential in professional training of the future dentists.