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A new nanomaterial or nano-filler in the form of multiwalled carbon nanotube-zinc oxide (MWCNT-ZnO) was synthesized for the purpose of modifying poly(butylene adipate-co-terephthalate) (PBAT) and its derivative (modified PBAT or MPBAT) through a melt-blending method (MPBAT was obtained by introducing maleic anhydride groups into PBAT). The effect of the new nano-filler on the properties of resultant nanocomposites was determined from the characterization of mechanical properties, morphology, crystallinity, thermal stability, barrier properties, hydrophilicity, conductivity, antibacterial property, and biodegradability. The results showed that MPBAT nanocomposites had stronger mechanical properties, better barrier properties, and higher electrical conductivity than PBAT nanocomposites. Scanning electron microscopy illustrated that MWCNT-ZnO had better compatibility with MPBAT than with PBAT. At 0.2% MWCNT-ZnO, the MPBAT/MWCNT-ZnO nanocomposite film exhibited the greatest mechanical properties (17.74% increase in tensile strength, 22.17% in yield strength, and 14.29% in elongation at break). When the MWCNT-ZnO content was 0.4%, the nanocomposite film demonstrated the best water vapor barrier ability (an increase of 30.4%). The MPBAT/MWCNT-ZnO film with 0.6% MWCNT-ZnO turned out to have the best oxygen barrier performance (an increase of 130% relative to pure PBAT). It was shown from the results of antibacterial evaluation that the new nanomaterial could impart PBAT and MPBAT with antibacterial activity. The biodegradability tests indicated that an MWCNT-ZnO content of 0.2% could slightly reduce the biodegradability, and when the content was higher than 0.2%, the weight loss rate would increase.

An organic ionic plastic crystal (OIPC) 2-hydroxyethyltrimethylammonium iodide (choline iodide) as an important component in solid electrolyte is synthesized and applied in dye-sensitized solar cells. It allows relatively rapid diffusion of the redox couple through the plastic crystal phase that is critical to the cell performance. The novel material, utilizing strong quaternary ammonium cation 2-hydroxyethyltrimethylammonium (HETA+) as a cation donor, is treated as matrix in electrolyte. At optimal condictions, the cell gives a short-circuit photocurrent density (Jsc), open-circuit voltage (Voc) and fill factor (FF) of 6 mA cm−2, 0.69 V and 63%, respectively. The corresponding overall conversion efficiency (η) is 2.5%. The results suggest that the OIPC is a promising solid electrolyte material for dye-sensitized solar cells applications.

The dispersion process and structure of impregnated CuO/ZrO2 systems were studied by x-ray diffraction (XRD) and extended x-ray absorption fine structure (EXAFS). The results showed that, after being calcined at 773 K, monolayer dispersed cupric nitrate decomposed into monolayer dispersed cupric oxide on zirconia's surface. The dispersion threshold of CuO was related to its precursor, cupric nitrate. The surface-dispersed Cu nearest coordination structure changed into about five equally long Cu–O bonds. Copyright © 2003 John Wiley & Sons, Ltd.