A poly(3,4-ethylenedioxypyrrole)-gold nanoparticle (Au)-tungsten oxide (PEDOP-Au@WO3 ) electrochromic supercapacitor electrode capable of optically modulating solar energy while simultaneously storing/releasing energy (in the form of charge) was fabricated for the first time. WO3 fibers, 50 to 200 nm long and 20 to 60 nm wide, were synthesized by a hydrothermal route and were electrophoretically deposited on a conducting substrate. Au nanoparticles and PEDOP were coated over WO3 to yield the PEDOP-Au@WO3 hybrid electrode. The inclusion of Au in the hybrid was confirmed by X-ray diffraction, Raman spectroscopy, and energy-dispersive X-ray analyses. The nanoscale electronic conductivity, coloration efficiency, and transmission contrast of the hybrid were found to be significantly greater than those of pristine WO3 and PEDOP. The hybrid showed a high specific discharge capacitance of 130 F g(-1) during coloration, which was four and ten times greater than the capacitance achieved in WO3 or PEDOP, respectively. We also demonstrate the ability of the PEDOP-Au@WO3 hybrid, relative to pristine PEDOP, to perform as a superior counter electrode in a solar cell, which is attributed to a higher work function. The capacitance and redox switching capability of the hybrid decreases insignificantly with cycling, thus establishing the viability of this multifunction hybrid for next-generation sustainable devices such as electrochromic psuedocapacitors because it can concurrently conserve and store energy.

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A photoactive electrode of cadmium sulfide (CdS) quantum dots and fullerene (C60) nanowhiskers (NW), free of a wide-gap semiconducting oxide support, has been fabricated for the first time, by growing CdS quantum dots using the successive ionic layer adsorption and reaction (SILAR) method over a layer of C60 nanowhiskers. Enhanced excited electron injection efficiency from the CdS quantum dots to C60 nanowhiskers was ascertained on the basis of maximum fluorescence quenching and shortest emission decay lifetimes in the CdS/C60 (NW) electrode compared to conventional CdS/C60 and CdS electrodes. Conducting atomic force microscope (C-AFM) revealed the larger nanoscale electronic conductivity for the CdS/C60 (NW) electrode relative to CdS/C60 or neat CdS electrodes. Kelvin probe force microscopy (KPFM) furnished an insight into how the downshift of the quasi Fermi level toward more positive potentials in the C60 nanowhiskers as compared to neat C60, is capable of providing an additional driving force for rapid electron transport within the photoanode. Photoelectrochemical cells based on the CdS/C60 (NW) and CdS/C60 electrodes were formed by employing a thin film of carboxylate functionalized multiwalled carbon nanotubes (MWCNTs)/poly­(dimethyldiallylammonium chloride) (PDDA) as the counter electrode. Rapid electron transport and high effective surface area of the C60 nanowhiskers manifested in higher photocurrents, photovoltage, and incident photon to current conversion efficiency (IPCE) for the cell based on the CdS/C60 (NW) electrode. The advantage of using MWCNT/PDDA electrode as the counter electrode was realized in terms of an overall enhancement in short circuit current (J SC), open-circuit voltage (V OC), and IPCE attained for the CdS/C60 (NW)-MWCNT/PDDA cell as opposed to cells based on platinum (Pt) as the counter electrode. Our method of combining CdS quantum dots with C60 nanowhiskers to yield an electrode that is superior to C60-based traditional electrodes on all counts is easily applicable to other visible light absorbing quantum dots and thus opens up exciting possibilities for a plethora of yet unexplored donor–acceptor architectures for high performance photoelectrochemical solar cells.

Composites of poly (3,4-ethylenedioxypyrrole) or PEDOP and poly (3,4-ethylenedioxythiophene) or PEDOT enwrapped Sb 2 S 3 nanorods have been synthesized for the first time for use as supercapacitor electrodes.Hydrothermally synthesized Sb 2 S 3 nanorods, several microns in length and 50À150 nm wide, offer high surface area and serve as a scaffold for coating conducting polymers, and are a viable alternative to carbon nanostructures. Fibrillar morphologies are achieved for the PEDOP-Sb 2 S 3 and PEDOT-Sb 2 S 3 films in contrast to the regular granular topologies attained for the neat polymers. The remarkably high nanoscale (B5 S cm À1) conductivity of the Sb 2 S 3 nanorods enables facile electron transport in the composites.We constructed asymmetric supercapacitors using the neat polymer or composite and graphite as electrodes. ) and excellent cycling stability (88 and 85% capacitance retention at the end of 1000 cycles) are delivered by the PEDOP-Sb 2 S 3 and PEDOT-Sb 2 S 3 cells relative to the neat polymer cells. A demonstration of a light emitting diode illumination using a light-weight, flexible, supercapacitor fabricated with PEDOP-Sb 2 S 3 and carbon-fiber cloth shows the applicability of Sb 2 S 3 enwrapped conducting polymers as sustainable electrodes for ultra-thin supercapacitors.

A new series of Pyrazolo [3,4-d]pyrimidine containing amide derivatives (8 a-l) were designed, synthesized, and evaluated for their in vitro α-amylase inhibitory activity. The IC 50 values of the target compounds ranged from 1.60 � 0.48 to 2.04 � 1.20 μM as compared to the standard acarbose 1.73 � 0.05 μM. All the Pyrazolo[3,4-d]pyrimidine amide derivatives displayed good inhibitory activities, while seven analogs (8 d, 8 f, 8 g, 8 h, 8 i, 8 j and 8 k) exhibited more or less equipotent activity with IC 50 values 1.77 � 2.84, 1.65 � 0.45, 1.66 � 2.24, 1.73 � 0.37, 1.60 � 0.48, 1.75 � 0.36 and 1.64 � 0.03 μM respectively. Further, the most potent α-amylase inhibitors 8 d and 8 k were also screened for their in vivo antidiabetic activity against alloxan induced diabetic rat model at the dose of 25 and 50 mg/kg. Oral administration of these tested compounds significantly reduced the fasting blood glucose levels in dose dependent manner. The hypoglycemic effects of these compounds were more evident at 3 h and 5 h after administration of tested compounds which was similar to the effect displayed by the positive control. In addition, the binding energies calculated from the docking studies with the α-amylase enzyme (PDB ID: 1HNY) and biological activities indicate that the compounds containing nitro moiety on the phenyl group contributed significantly towards the antidiabetic activity.[a] Dr.