Vol 484, No 2 (2019)

The reduction of tungsten and molybdenum oxide compounds (WO₃, MoO₃, MgWO₄, MgMoO₄, and CaMoO₄) with calcium vapor at 800–860°С and a residual argon pressure of 5–10 kPa has been studied. As previously during the reduction with magnesium vapor, the spatial separation of the reaction products was observed, namely, the major portion of the calcium oxide formed in the reaction was deposited outside the reaction zone. A specific feature of the reduction of MgWO₄ and MgMoO₄ is that the magnesium is first replaced by calcium. The resulting magnesium metal acts as a reducing agent, and the magnesium oxide, along with calcium oxide, forms a crust on the surface of the reaction mass. Analysis of the experimental results shows that the reduction of oxide compounds with magnesium and calcium vapors at a residual argon pressure of more than 5 kPa proceeds via the electronically mediated reaction mechanism without direct physical contact between the reactants.

ZrO₂/Y₂O₃ nanoparticles containing 0, 3, and 10 mol % Y₂O₃ were synthesized under hydrothermal conditions. The structural and optoelectronic properties of the nanoparticles were studied using appropriate measurement techniques. From the synthesized ZrO₂–Y₂O₃ nanostructured systems, electron-conductive thin-film photoelectrodes were fabricated and used to develop perovskite solar cells (PSCs) with the device configuration glass/FTO/ZrO₂–Y₂O₃/CH₃NH₃PbI₃/Spiro-MeO-TAD/Au. Comparative study of the PSC photovoltaic characteristics under 1000 W/m² illumination (AM1.5G) has shown that the devices based on ZrO₂–Y₂O₃ photoelectrodes exhibit a higher power conversion efficiency than the PSC based on undoped ZrO₂ photoelectrodes.