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Defect and interface engineering have been shown as effective strategies towards sustainable hydrogen production, but detailed descriptions of the origin of performance enhancements is not established. Here, we synthesize a model heterostructure interface, CoSe2-MoSe2/PEDOT, to unravel its bifunctional capability. Low eta(10) of -0.20 V for HER and 1.53 V for OER verified the electrocatalytic performance of this catalyst. We systematically reveal intrinsic point defects and lattice dislocations in these heterostructures. Atomic scale electron microscopy studies disclose presence of V-Se and Mo-Mo bond defects. Spectroscopic techniques are employed to show the altered electronic properties that promote surface oxidation due to the presence of defects. In contrast to MoSe2 or MoSe2/PEDOT, defect rich CoSe2-MoSe2/PEDOT showed accelerated reaction kinetics with much lower Tafel slopes. Essentially, generation of anion vacancies and metallic Mo-Mo bonds provide additional sites with improved adsorption properties of the reaction intermediates. This catalyst exhibits excellent electrocatalytic stability upon cycling for both half-cell reactions.

The preparation of polyfuran-graphene (PFu/GR) and polyfuran-multi-walled carbon nanotube (PFu/MWCNT) nanocomposites was carried out via a plasma polymerization. The characterizations of the pure GR, MWCNTs and the nanocomposites coated with PFu were performed using Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and scanning electron microscopy analyses. Counter electrodes prepared using the nanocomposites were used in dye-sensitized solar cells (DSSCs), demonstrating an enhancement in cell performance. The maximum efficiency of the DSSC with the PFu/GR counter-electrode with a short-circuit photocurrent density of 32.26 mA/cm(2) was 5.06%, which is much higher than that of the short-circuit photocurrent density of 14.11 mA/cm(2) and efficiency of 2.13% in the cell using the GR counter electrode. This was attributed to the enhanced conductivity between the PFu-based counter electrode and the electrolyte.

This study presents the modification of multi-walled carbon nanotube (MWCNT) with poly(3-hexylthiophene) (P3HT) and polypyrrole (PPy) through the fast, versatile, and environmentally friendly process of radiofrequency (RF)-rotating plasma polymerization. Morphological characterization of composites was performed using scanning electron microscopy (SEM) and showed that the P3HT and PPy conducting polymers coated the MWCNT surface. The surface properties of the MWCNT composites were determined using Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and SEM analysis. MWCNT composites were used as cathodes in dye-sensitized solar cells (DSSCs). The short circuit current densities of P3HT/MWCNT- and PPy/MWCNT-based DSSCs were found to be 5.61 and 4.19 mA/cm(2), respectively. POLYM. COMPOS., 39:668-674, 2018. (c) 2016 Society of Plastics Engineers

Hybrid solar cells have been fabricated using perylene monoimide-monoanhydride dyes with nanorod zinc oxide electrodes as electron transporting layers. We have investigated the influence of the spacer alkyl chain length of perylene monoimide-monoanhydride (PMIMA) dyes on the device performance in hybrid solar cells using nanorod zinc oxide electrodes. Nanorod zinc oxide electrodes with 50150 nm of diameter were synthesized in the presence of PEG400 by using microwave heating method. We observed that the dyes with longer and brunched alkyl chains exhibit higher efficiencies in hybrid solar cells. We report the highest efficiency obtained with zinc oxide nanorods under standard conditions for perylene monoimide-monoanhydride derivative with PMIMA_1 that performs 400 mV open circuit voltage, 2.81 mA/cm(2) short-circuit current and 0.59% overall conversion efficiency. (C) 2009 Elsevier B.V. All rights reserved.