A monoamine–dithiol mixture is used to prepare homogeneous Cu(In, Ga)Se2 (CIGSe) molecular precursor solution, which yields a highly sulfur depleted CIGSe thin-film solar cell with a power conversion efficiency of 12.2%.

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Boron nitride nanotubes (BNNTs) are promising nanofillers in polymer nanocomposites due to their high strength and high modulus as well as thermal and chemical stability. In BNNTs nanocomposites, the orientation of BNNTs and interfacial stress transfer between BNNTs and the matrix determine the nanocomposite performance. In this study, Raman spectroscopy was used to measure the orientation of BNNTs and interfacial stress transfer of BNNTs in polyacrylonitrile (PAN) fibers. The orientation of BNNTs in the nanocomposite fibers could be tuned by postdrawing fibers, and fibers with higher draw ratios show higher BNNTs orientation. In addition, fibers with higher draw ratios show a higher Raman band shift rate than that of low draw ratio fibers, which indicates enhanced interfacial shear stress between the PAN matrix and BNNTs. This study shows that highly oriented BNNTs are critical to the mechanical properties of the BNNTs reinforced polymer nanocomposites.

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Bi‐component, polyacrylonitrile (PAN)/carbon nanotube (CNT) fibers were processed, at different core‐sheath area ratios, by gel spinning. A percolated CNT network at 10 wt% CNT in the sheath enhanced electrical conductivity as compared to the neat PAN fiber, while PAN polymer in the core contributed to the good mechanical properties. Fibers with relatively thin sheath allowed overall CNT loading as low as 3.7 wt% to be made with good electrical conductivity, and PAN stabilization by Joule heating was demonstrated. Such fibers with combined good mechanical properties and electrical conductivity can also potentially be used for electrical heating of fabrics, for making smart textiles, and for electromagnetic interference shielding.

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Mechanical reinforcement of polymer nanocomposites with pristine single wall carbon nanotubes (SWNTs) beyond 1 wt % loading is challenging because SWNT−SWNT contacts generate filler aggregation and reduce polymer−filler interaction. Furthermore, SWNTs cannot be covalently functionalized without affecting their inherent properties. In this study, filler individualization and filler−matrix interactions were tuned by helically wrapping the SWNTs with poly(methyl methacrylate) (PMMA), a noncovalent method, and also by changing the PMMA molecular weight. Polyacrylonitrile nanocomposite fibers were produced by dry-jet wet spinning using 1 and 5 wt % PMMA-wrapped SWNTs. Improvement in the filler dispersion and the fiber mechanical properties upon using PMMA-wrapped SWNTs, as compared to SWNTs without PMMA-wrapping, is reported. It is demonstrated that PMMA-wrapping becomes part of the filler−matrix interphase. Increasing the molecular weight of the PMMA wrapping improves SWNT individualization but appears to reduce filler−matrix interaction. Relatively high fiber mechanical properties were obtained when SWNTs wrapped with relatively low molecular weight (15000 g/mol) PMMA were used. Potential applications of these fibers have been discussed.