Chemical synthesis

Based on thermodynamic constants, the concentration limits of the initial mercury and cadmium-containing salts and the pH range at which depositions of HgS and CdS are possible without the formation of HgO and Cd(OH)2 were calculated. The limits of the formation conditions of the Hg1–xCdxS solid solution in the thiosulfate-citrate-carbonate-thiourea system were defined by the overlap area between the constructed HgS and CdS deposition zones.

Based on thermodynamic constants, the concentration limits of the initial zinc-containing salt and the range of pH values at which the depositions of ZnS and ZnSe without Zn(OH)2 are possible were calculated. The boundary conditions of the formation of the ZnSxSe1–x solid solution in the hydroxide-hydrazine-thiourea-selenium system were defined by the overlap area between the constructed ZnS and ZnSe formation zones. The task of complex intermolecular interaction between complexed zinc ions and two chalcogenizers in the working solution was solved on the basis of mathematical calculations.

Solid solutions films of mercury sulfide-selenide (HgS1–xSex) were synthesized on glass substrates by the chemical bath deposition method. Theoretical calculations of the boundary conditions for the HgS and HgSe formation in the mercury-tartrate-thiourea-selenosulfate system were made. The boundary conditions of HgS1–xSex were defined by the overlap area between the constructed HgS and HgSe formation zones. The X-ray diffraction and elemental analysis showed that the obtained films are single-phase and consist of HgS1–xSex substitutional solid solutions in zincblende modification.

The present study focuses on a new application of a decision-making process using the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) method for the optimization of the chemical synthesis output. This investigation is important as many chemical reactions have been performed in labs without any analysis of their optimization. The factors that affect the chemical synthesis output such as catalyst, nanosensor network, and temperature have been considered in this study.