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Thermoelectric (TE) materials are possible solutions of the current problems in the energy sector to overcome environmental pollution, increasing energy demand and the decline of natural resources. Thermoelectric materials are a promising alternative for the conversion of waste heat to electricity. Nanocrystalline PbTe powder was synthesized by a simple chemical method at room temperature and systematically investigated at various durations as samples A1–A5. Fourier Transform infrared spectroscopy (FTIR), x-ray diffraction (XRD), microstructural analysis by scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS) confirmed the composition of the samples. TE parameters as thermo-emf of samples A1–A5 and electrical conductivity were measured. The cyclic voltammetry gives a band gap of 0.25 eV, which is in agreement with the optical band gap of the material. The A4 sample has an average crystal size of 36 nm with preferred orientation in (200) verifying the cubic morphology. The obtained TE parameters are beneficial for the non-uniform TE materials which might be due to strong current boundary scattering and extremely low thermal conductivity of the samples.

Thin film of Lead oxide (PbO) was prepared by spray pyrolysis technique on glass substrate at 250°C. The cyclic voltammetry measurement was carried out to study the oxidation reduction reactions of non-aqueous lead ions at various molar concentrations which is from 0.01M to 0.09M. Elecrochemical studies were carried out with Ag/AgCl as a reference electrode , Pt as working electrode while platinum mesh as counter electrode.Lead oxide appears to be poisonous yellow or reddish yellow solid. Structural characterization of films was analyze with X- ray diffraction (XRD) and optical band gap was determined by UV-Vis Spectroscopy.

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Lead Sulphide (PbS) thin film was deposit by chemical bath deposition (CBD) process on the glass substrate at room temperature for various time intervals. The precursors used for this deposition are lead acetate since as a supply of lead ions (Pb2+) and thiourea the same as the supply of sulfide ions (S2-) with 0.1M concentration. The pH of the mixed precursors solution was maintained at 9.5-10 by addition of drop by drop ammonia very slowly. The cause of deposition time for different hours studied. The influence of deposition time on properties of PbS film was investigated. The color of films appears black-gray after taking out of the bath. The thickness of the film is increased with increase in deposition time. The electrical resistance and resistivity were 500MΩ and 18.75 MΩ-cm and band gap measured as a function of temperature using D.C. four probe methods was 0.3742 eV. The Cyclic Voltammetry (CV), Linear Sweep Voltammetry (LSV), Chronoamperometry were studied by using potentiostat.

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