Synthesis and Study of the Properties of Photocatalytic Compositions Based on Sro/Bi2O3 and (Bio)2CO3 Solid Solutions with Modifying Additives of Transition Metals Cu, Mn, Fe

In this work, we studied the effect of doping with d metals (Me: Mn, Fe, Cu) on the photocatalytic activity and optical properties of the hetero-structured, bismuth-containing Sr1-xMexBi4O7 / (BiO)2CO3 photo-catalyst, where x = 0.01–0.05. The stages of oxidative pyrolysis of precursor organometallic complexes with sorbitol by differential scanning calorimetry have been studied. The first stage of oxidative destruction is induced by the influence of nitrate-ion and terminates at temperatures below . The second stage of pyrolysis is associated with a further thermal degradation of sorbitol to pyrolytic carbon in the temperature range 113 - . The third stage 287–462°C is associated with the combustion of the formed pyrolytic carbon. The final stage of pyrolysis occurs in the temperature range of 462-with the formation of the target synthesis products. It has been established that Cu is the most effective dopant. In contrast to other metals, doping with copper results in the formation of a solid solution in the CuO-SrBi4O7 system. Compared to the initial SrBi4O7, as a result of doping Cu in an amount of 5 at. % the largest change in the band gap from 2.77 to 2.62 eV is achieved. The efficiency of photo-catalysis (estimated by the half-conversion of methylene blue) of the Cu0.05Sr0.95Bi4O7 / (BiO) 2CO3 composition turned out to be 2.3 times higher than the initial - undoped catalyst; and 3.1 times higher than in the non-catalytic process.

Chemical doping engineering by utilizing trilacunary Keggin polyoxometalates as a dopant for high performance perovskite solar cells

Trilacunary Keggin type BiW9-Zn was first used as a cost-effective dopant for Spiro-OMeTAD and the PCE was enhanced to 19.56%.

Graphene nanoflakes as effective dopant to Li-based greases

Lithium and complex lithium greases were modified by few-layer graphene nanoflakes. Tribological tests demonstrate improvement of the lubricating characteristics, e.g. increase of the welding load and decrease of the wear scar diameter after the modification. XPS method showed occurrence tribochemical reaction between lithium 12-hydroxystearate molecules and graphene nanoflakes surface during exploitation of the grease. It was shown that graphene nanoflakes are corrosion-inactive in lubricating compositions and compatible with modern additive packages.

Cost-effective dopant-free star-shaped oligo-aryl amines for high performance perovskite solar cells

Cost-effective imidazole-based star-shaped arylamines were used as dopant-free hole transport materials (HTMs) for high performance perovskite solar cells (17.47%).

New Polymer Systems for Use in Organic Photovoltaics

In this paper, new polymers for use in organic photovoltaics were investigated. PPBI, PNBI and copolymer MULT are considered as a potential alternative or an effective dopant for P3HT and PCBM. The choice of these materials allows us to find out new information on the prospects and properties of heterocyclic polymers — for thermal stability and resistance to the environment for organic solar cells. The levels of HOMO and LUMO of new heterocyclic polymers were measured, and the results were compared with those of P3HT: PCBM. The level of new polymer MULT photoluminescence was determined. The absorption blend for P3HT: PCBM peak absorption shift was detected by adding 5% (by mass) of the new polymer MULT, the value of 30–40[Formula: see text]nm to longer wavelengths. Data obtained by cyclic voltammetry showed deep HOMO levels of heterocyclic polymers in values of about [Formula: see text]6[Formula: see text]eV, which is promising in terms of acceptor properties.