Electrical resistivity of nanocrystalline PbS grown in a polymer matrix

Abstract

PbS particles of average diameters ranging from 9.9 to 18.0 nm have been synthesized within a polyacrylamide matrix. The percolative chains of these particles exhibit intrinsic semiconducting behavior at temperatures higher than 340 K. The estimated band gap for these particles are found to be much higher than that of bulk PbS being in the range 1.03 to 1.49 eV. The low-temperature conductivity of these composites appears to be controlled by an electron tunneling mechanism.

Relationship between crystal morphology and photoluminescence in polynanocrystalline lead sulfide thin films

“…films with an average grain size of about 200-300 nm [7]); CBD can be extended to obtain nanocrystalline PbS by varying the deposition parameters such as reaction time, temperature, pH and additives content in the deposition bath [8]. Most of the reported nanocrystalline PbS are related to PbS nanoparticles imbedded in a glass-ceramics, glass or organic matrix [9][10][11]. PbS nanocrystals have been prepared by chemical methods in the presence of a capping agent [12], electrodeposition techniques [13] and by solvothermal [14], sonochemical [15] and microwave assisted techniques [16].…”

Silica-coated ZnS quantum dots as fluorescent probes for the sensitive detection of Pb2+ ions

“…The band gap of CuS nanocrystals has been reported to be in the range between 1.25 and 2.81 eV (Mageshwari et al 2011;Nair et al 1998;Raevskaya et al 2004;Yildirim et al 2009). The band gap of PbS nanocrystals has been reported to be in the range 0.5-2.32 eV (Joshi et al 2004;Mukherjee et al 1994;Nanda et al 2002) and even as high as 5.2 eV (Thielsch et al 1998). Although the exact band gaps of CuS and PbS ultrafine grains formed on the surface of ZnS cores are unknown, we assume that the electron and hole transfer from the excited ZnS to the energy levels of PbS may be faster than to that of CuS, bringing about the quicker fluorescence quenching by Pb 2?…”

Polychromatic Source Excitable and Enhanced Green Photoluminescence of ZnO Nanoparticles Dispersed in High Molecular Weight

“…As a result, a broad excitation peak that allowed the use of even polychrocromatic excitation source was obtained. Although there are a number of reports on the growing of nanoparticles in polymer matrix, [12][13][14][15] however, in our knowledge, similar report on the dispersing of ZnO nanoparticles in HMWP was not available, in particular that relates to the enhancement of PL intensity and producing polychromatic source excitable ZnO composites. This approach is also potential for producing luminescent polymer electrolyte nanocomposites.…”