Solvent vapour annealed (SVA) technique was successfully used in controlling the morphology of polymer thin film blending with low molecular weight chromophoric (LMWC) molecules.

Nonlinear absorption (NLA) of hydrogenated nanocrystalline silicon (nc-Si:H) has been investigated through the open aperture Z-scan method for the photon energy of the incident irradiance slightly less than the bandgap of the sample. NLA responses have been observed to be highly sensitive to the wavelength and intensity of the incident irradiance as well as to the bandgap of the sample, indicating greatly tunable NLA of nc-Si:H. The band tail of nc-Si:H appears to play a crucial role in such NLA responses.

Nonlinear refraction (NLR) of hydrogenated nanocrystalline silicon (nc-Si:H) has been investigated through the close aperture Z-scan method. We demonstrate a significant NLR and a unique feature of controllable NLR characteristics between saturable and Kerr NLR with the incident photon energy. We numerically evaluate the proportion of these two mechanisms in different wavelengths by a modified NLR equation. The band tail of nc-Si:H appears to play a crucial role in such NLR responses.

The preparation of a new antiwear composites based on polyurethane (PU) elastomer blended and modified with ultra-high molecular weight polyethylene (UHMWPE) has been described. The performance of PU-based composites (PUC) with different proportions of UHMWPE micropowder was demonstrated with mechanical testing, thermal gravimetric analysis, scanning electron microscopy, and friction and wear testing. Compared with the single PU elastomeric material, the composites showed excellent mechanical properties (including tensile strength, break elongation, and flexible modulus), thermal stability, extremely good wear resistance, and low coefficient of friction, especially in water. PUC fabricated in this study is a kind of typical wear-resistant material, which is especially suitable for water-lubricated bearings widely used in metallurgy, mining, hydraulic engineering, and other harsh working conditions. C

We have carried out an investigation of multiple exciton generation (MEG) in Si quantum dots (QDs) and its application in optoelectronic devices. A simple yet effective statistical model has been proposed based on Fermi statistical theory and impact ionization mechanism. It is demonstrated that the MEG efficiency depends on both the radius of Si QDs and the energy of incident photons, with the MEG threshold energy in the range of ∼2.2–3.1 Eg depending on the dot radius. While limited improvement has been observed in power conversion efficiency of single stage solar cells, MEG in Si QDs exhibits prospective for application in ultraviolet detectors due to the high internal quantum efficiency under short incident light.