A single-precursor solution approach is developed for depositing stoichiometric BiSI thin films featuring pure paraelectric orthorhombic (Pnam) phase. The compact and homogenous films are composed of flake-shaped grains oriented anti-planar to the substrate and display a sharp optical transition corresponding to a bandgap of 1.57 eV. Optical and Raman signatures of the thin films are rationalized using the quasiparticle G0W0@PBE0 and Density Functional Perturbation Theory calculations. Electrochemical impedance spectroscopy revealed n-type doping with valence and conduction band edges located at 4.6 and 6.2 eV below vacuum level, respectively. Planar BiSI solar cells are fabricated with the architecture: glass/FTO/SnO2/BiSI/F8/Au, where F8 is poly(9,9-din -octylfluorenyl-2,7-diyl), showing record conversion efficiency of 1.32% under AM 1.5 illumination.

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There is an extended concern related to renewable energies in South America. Particularly the Uruguayan government is encouraging initiatives in solar, biofuels and eolic wind energy issues. On the other hand, and in a similar manner than in other countries, Uruguay celebrates the "Science and Technology Week", an activity annually organized, focused on sharing knowledge between scientists and technologists and society. In 2012, this week was devoted to energy and sustainability. In this framework we carried out an interactive activity in five primary school classes with the aim of bringing materials science and solar energy to children between 10 and 12 years old. In the beginning of the activity we asked students to complete a brief survey containing a few questions about materials and energy. This survey allowed us to further the children's knowledge about these topics. Then, we introduced materials science history relating it with mankind development. From the active participation of children in the activity, we derived to materials applied in solar cells, performing demonstrations with real solar cells and showing their importance for improving our country energetic efficiency while preserving the environment. At the end of each activity students showed great enthusiasm about including alternative energies in their daily life. Furthermore, they realized the importance of materials science, and were capable of understanding the relation between materials and the development of solar cells. We consider the spread of this activity as an excellent way of creating consciousness from an early age, which will help in the achievement of a more sustainable country.