This may also be due to the increase in the density of defect states, which results in the extension of tailing of bands. The value of refraction index and extinction coefficient increases with increasing photon energy for all samples of a-(PbSe)100−x Cd x . From temperature dependence of dc conductivity measurements, it may be concluded that conduction is taking place through the thermally activated process over the entire range of investigation. The pre-exponential factor shows an overall decreasing trend with increasing Cd content. The decrease in σ0 may be due to the change in the Fermi level on the addition of Cd in

the lead chalcogenide system. Finally, the suitability of these nanoparticles of lead

chalcogenides for various applications especially in solar cells can be understood on the basis VX-809 chemical structure of these properties. Acknowledgments This paper was funded by the Deanship of Scientific Research (DSR), King Abdulaziz University, Jeddah, under grant number (80-130-D1432). The authors, therefore, acknowledge with thanks DSR technical and financial support. References 1. Mahapatra PK, Roy CB: Photoelectrochemical cells with mixed polycrystalline n-type CdS-PbS and CdS-CdSe electrodes. Electrochem Acta 1984, 29:1435.CrossRef 2. Kenawy MA, Zayed HA, Ibrahim AM: Structural, electrical and optical properties of ternary CdS x Se 1−x thin films. Indian J

Pure & Appl Phys 1991, 29:624. 3. Deshmukh LP, More BM, Holikatti SG: Preparation and properties of (CdS) x -(PbS) 1−x thin-film composites. Bull Mater Sci 1994, 17:455.CrossRef Rapamycin manufacturer 4. Al-Ghamdi AA, Al-Heniti S, Khan SA: Structural, optical and electrical characterization of Ag doped lead chalcogenide Olopatadine (PbSe) thin films. J Luminescence 2013, 135:295.CrossRef 5. Nair PK, Garcia VM, Hernandez AB, Nair MTS: Photoaccelerated chemical deposition of PbS thin films: novel applications in decorative coatings and imaging techniques. J Phys D: Appl Phys 1991, 24:1466.CrossRef 6. Schluter M, Martinez G, Cohen ML: Pressure and temperature dependence of electronic energy levels in PbSe and PbTe. Phys Rev B 1975, 12:650.CrossRef 7. Yuan S, Krenn H, Springholz G, Bauer G: Dispersion of absorption and refractive index of PbTe and Pb 1−x Eu x Te ( x < 0.05) below and above the fundamental gap. Phys Rev B 1993, 47:7213.CrossRef 8. Nimtz G, Schlicht B: Narrow-gap lead salts. In Narrow-Gap Semiconductors. New York: Springer-Verlag; 1983:98. 9. Chesnokova DB, Moshnikov VA, Gamarts AE, Maraeva EV, Aleksandrova OA, Kuznetsov VV: Structural characteristics and photoluminescence of Pb 1−x Cd x Se ( х = 0–0.20) layers. J Non-Crystt Solids 2010, 356:2010.CrossRef 10. Bencherif Y, Boukra A, Zaoui A, Ferhat M: Lattice dynamics study of lead chalcogenides. Infrared Phys Tech 2011, 54:39.CrossRef 11.