The English version of the article have been published in the international edition of the journal: Andrey V. Pozdin, Tatyana D. Ovsyukova, Alena S. Klevakina, Vyacheslav F. Markov, Larisa N. Maskaeva. Thermodynamic evaluation of chemical compounds of PbS films doped with gallium. Butlerov Communications A. 2023. Vol.5. No.1. Id.3. DOI: 10.37952/ROI-jbc-A/23-5-1-3. The narrow-gap semiconductor with the PbS rock salt structure continues to arouse considerable scientific interest due to its unlimited potential applications as infrared photoresistors, photodiodes, lasers, strain gauges, environmental monitoring devices. However, the global desire for more efficient energy management has drawn attention to the potential thermoelectric applications of this material. A well-known technique that provides the required functional properties, in particular thermoelectric properties, is the doping of lead sulfide films with both cations and anions. Several significant developments of thermoelectric materials based on PbS by doping with group IIIA transition elements are being discussed by researchers. The rare combination of a large effective mass and a low deformation potential in gallium-doped lead sulfide contributes to a high thermoelectric efficiency. Most researchers prefer the preparation and doping of PbS with gallium by thermal alloying. However, low-temperature chemical deposition of thin PbS(Ga) films from aqueous solutions has significant advantages: simplicity, low cost, and the possibility of its introduction into industrial production. In the present work, a preliminary analysis of ionic equilibria in the reaction system «Pb(CH3COO)2 - Ga2(SO4)3 - Na3C6H5O7 - NH4OH - N2H4CS» made it possible to establish the concentration regions of the joint formation of solid phases PbS and Ga3S2. On the basis of the chosen formulation, homogeneous PbS(Ga) films with a thickness of up to ~610 nm were obtained for the first time by chemical deposition at a temperature of 353 K for 180 min. on glass substrates. The energy-dispersive analysis revealed an excess of lead ions in comparison with sulfur at a gallium content of up to 0.44 at.%, which is consistent with the n -type conductivity of the studied films.
