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Green DES (ChCl/urea fluid) as a novel surface treatment reagent has been proposed for improving the thermoelectric (TE) performance of PEDOT:PSS films and demonstrated satisfying effects as expected. Simultaneous increases were found in the electrical conductivity and Seebeck coefficient, which achieved further improvement by raising the treating temperature. This additional enhancement was probably attributed to that higher temperature led to decreased viscosity thus a better interaction between the DES mixture and the film surface. The maximum electrical conductivity and Seebeck coefficient were found at 120 °C, reaching 85.6 S cm −1 and 30.1 μV K −1 . Further TE improvement was obtained when DMSO was introduced to make a mixture with DES at different ratios to act as the treatment reagent, giving rise to an optimized power factor of 25.26 μW m −1 K −2 with the corresponding electrical conductivity and Seebeck coefficient being 424.2 S cm −1 and 24.4 μV K −1 , respectively. [ABSTRACT FROM AUTHOR]

ABSTRACT As conventional organic solvents present inherent toxicity, deep eutectic solvents (DES) have been considered as excellent candidates due to their green characteristics. In this work, thermoelectric properties enhancement of PEDOT:PSS films is achieved by introducing DES as an additive and post-treatment reagent. Direct addition and post-treatment approaches lead to a maximum Seebeck coefficient of 29.1 μV K−1 and electrical conductivity of 620.6 S cm−1, respectively. In addition, an optimal power factor is obtained by DES post-treatment, reaching up to 24.08 μW m−1 K−2, which is approximately four orders of magnitude higher than the pure PEDOT:PSS. Assuming a thermal conductivity of 0.17 W m−1 K−1, the maximum ZT value is estimated to be 0.042 at 300 K. Further, atomic force microscopy and X-ray photoelectron spectroscopy are performed and suggest that the remarkably enhanced electrical conductivity originates from the removal of the excess insulating PSS and the phase separation between the PEDOT and PSS chains. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015, 53, 885-892 [ABSTRACT FROM AUTHOR]

MoS2 has attracted attention as a promising hydrogen evolution reaction (HER) catalyst and a supercapacitor electrode material. However, its catalytic activity and capacitive performance are still hindered by its aggregation and poor intrinsic conductivity. Here, hollow rGO sphere-supported ultrathin MoS2 nanosheet arrays (h-rGO@MoS2) are constructed via a dual-template approach and employed as bifunctional HER catalyst and supercapacitor electrode material. Because of the expanded interlayer spacing in MoS2 nanosheets and more exposed electroactive S-Mo-S edges, the constructed h-rGO@MoS2 architectures exhibit enhanced HER performance. Furthermore, benefiting from the synergistic effect of the improved conductivity and boosted specific surface areas (144.9 m2 g−1, ca. 4.6-times that of pristine MoS2), the h-rGO@MoS2 architecture shows a high specific capacitance (238 F g−1 at a current density of 0.5 A g−1), excellent rate capacitance, and remarkable cycle stability. Our synthesis method may be extended to construct other vertically aligned hollow architectures, which may serve both as efficient HER catalysts and supercapacitor electrodes. [ABSTRACT FROM AUTHOR]

MoS2 has attracted attention as a promising hydrogen evolution reaction (HER) catalyst and a supercapacitor electrode material. However, its catalytic activity and capacitive performance are still hindered by its aggregation and poor intrinsic conductivity. Here, hollow rGO sphere-supported ultrathin MoS2 nanosheet arrays (h-rGO@MoS2) are constructed via a dual-template approach and employed as bifunctional HER catalyst and supercapacitor electrode material. Because of the expanded interlayer spacing in MoS2 nanosheets and more exposed electroactive S-Mo-S edges, the constructed h-rGO@MoS2 architectures exhibit enhanced HER performance. Furthermore, benefiting from the synergistic effect of the improved conductivity and boosted specific surface areas (144.9 m2 g−1, ca. 4.6-times that of pristine MoS2), the h-rGO@MoS2 architecture shows a high specific capacitance (238 F g−1 at a current density of 0.5 A g−1), excellent rate capacitance, and remarkable cycle stability. Our synthesis method may be extended to construct other vertically aligned hollow architectures, which may serve both as efficient HER catalysts and supercapacitor electrodes. [ABSTRACT FROM AUTHOR]