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In this work, a multifunctional binder with self‐healing, flame retardant, high conductivity, and abundant polar groups is prepared by the free radical polymerization method and applied to lithium–sulfur (Li‐S) batteries to achieve high safety and exceptional electrochemical performance. The self‐healing characteristic of binder induced by intermolecular hydrogen bonds and SS dynamic covalent bonds can repair volume expansion cracks. The polar groups and excellent conductivity endue binder with strong chemisorption on polysulfides and fast charge transportation, which can effectively inhibit the shuttle effect and accelerate polysulfides redox kinetics. More important, the considerable flame retardant performance of binder can improve the safety of the LiS batteries. As a result, the LiS cells using FHCP binder deliver an outstanding cycle stability of a high‐capacity retention rate of 85% after 100 cycles at 0.2 C, and a high reversible area specific capacity of 5.25 mAh cm–2 at a sulfur loading of 4.72 mg cm–2 and a correspondingly lean electrolyte condition (E/S ratio = 6 µL mg–1). [ABSTRACT FROM AUTHOR]

We report on the discovery of the first two examples of cationic palladium(II)‐oxo clusters (POCs) containing f‐metal ions, [PdII6O12M8{(CH3)2AsO2}16(H2O)8]4+ (M=CeIV, ThIV), and their physicochemical characterization in the solid state, in solution and in the gas phase. The molecular structure of the two novel POCs comprises an octahedral {Pd6O12}12− core that is capped by eight MIV ions, resulting in a cationic, cubic assembly {Pd6O12MIV8}20+, which is coordinated by a total of 16 terminal dimethylarsinate and eight water ligands, resulting in the mixed PdII‐CeIV/ThIV oxo‐clusters [PdII6O12M8{(CH3)2AsO2}16(H2O)8]4+ (M=Ce, Pd6Ce8; Th, Pd6Th8). We have also studied the formation of host‐guest inclusion complexes of Pd6Ce8 and Pd6Th8 with anionic 4‐sulfocalix[n]arenes (n=4, 6, 8), resulting in the first examples of discrete, enthalpically‐driven supramolecular assemblies between large metal‐oxo clusters and calixarene‐based macrocycles. The POCs were also found to be useful as pre‐catalysts for electrocatalytic CO2‐reduction and HCOOH‐oxidation. [ABSTRACT FROM AUTHOR]

This paper reports on the application of poly (3,4‐ethylenedioxythiophene)/carbon nanotubes (PEDOT/CNT) material for the construction of a hybrid supercapacitor utilizing iodide redox‐active electrolyte. To address the advantages in terms of electrochemical performance, comparison has been made to the system using conventional activated carbon (AC) electrodes. Despite limited specific surface area of the polymer‐based material, the PEDOT/CNT cell demonstrates reasonably high electrical parameters (vs. highly porous AC), especially those normalized per volume or total mass of the device. Interestingly, it also exhibits more stable self‐discharge characteristics over operation time which shall be assigned to smaller fraction of free polyiodides generated in the cell in the presence of the low‐surface‐area polymer electrode, in addition to their strong confinement in the polymer network, thus suppressing redox‐shuttling. Pursuing the mechanistic studies, we have managed to detect (using the electrocatalytic WO3‐based voltammetric probe) the presence of undesirable iodates but at lower concentrations in a case of the PEDOT/CNT‐based capacitor. [ABSTRACT FROM AUTHOR]

Poly(4‐vinylpyridine)‐modified copper(I) oxide photocathodes, bare or decorated with palladium nanoparticles, can be used for the visible‐light‐driven selective reduction of CO2, mostly to methanol and carbon monoxide (in the absence of Pd cocatalyst) or formic acid and carbon monoxide (in the presence of Pd cocatalyst). The photocathode materials, which are composed of hierarchically deposited (onto transparent fluorine‐doped conducting glass electrode) Cu2O (inner layer) and poly(4‐vinylpyridine) (P4VP) polyelectrolyte film (outer‐layer), with or without dispersed Pd nanoparticles, have been fabricated and examined using electrochemical methodology, atomic force microscopy, and various spectroscopic techniques, including the Raman approach. While the physicochemical characteristics of Cu2O, including the oxide identity and its semiconducting properties, are not largely affected by the interfacial modification with P4VP, the photostability of the hybrid photocathode is significantly improved. The P4VP‐modified Cu2O exhibits reasonable durability during photoelectrochemical reduction of CO2 upon illumination with sunlight in semi‐neutral medium (Na2SO4). While Cu2O can be identified using Raman spectroscopy as the sole bulk component of the semiconducting film, the XPS data imply that the Cu2O surface is likely to be partially reduced during prolonged operation. Introduction of palladium cocatalyst seems to improve distribution (collection and transport) of photoelectrons at the photoelectrochemical interface and affects the CO2‐electroreduction mechanism. [ABSTRACT FROM AUTHOR]

The 48‐FeIII‐containing 96‐tungsto‐16‐phosphate, [FeIII48(OH)76(H2O)16(HP2W12O48)8]36− (Fe48), has been synthesized and structurally characterized. This polyanion comprises eight equivalent {FeIII6P2W12} units that are linked in an end‐on fashion forming a macrocyclic assembly that contains more iron centers than any other polyoxometalate (POM) known to date. The novel Fe48 was synthesized by a simple one‐pot reaction of an {Fe22} coordination complex with the hexalacunary {P2W12} POM precursor in water. The title polyanion was characterized by single‐crystal XRD, FTIR, TGA, magnetic and electrochemical studies. [ABSTRACT FROM AUTHOR]

The ability of Pt nanostructures to induce the splitting of the II bond in iodine (triiodide) molecules is explored here to enhance electron transfer in the iodine/iodide redox couple. Following the dispersal of Pt nanoparticles at 2 % (weight) level, charge transport was accelerated in triiodide/iodide-containing 1,3-dialkylimidazolium room-temperature ionic liquid. If both Pt nanoparticles and multi-walled carbon nanotubes were introduced into the ionic-liquid-based system, a solid-type (nonfluid) electrolyte was obtained. By using solid-state voltammetric (both sandwich-type and microelectrode-based) methodology, the apparent diffusion coefficients for charge transport increased to approximately 1×10−6 cm2 s−1 upon the incorporation of the carbon-nanotube-supported iodine-modified Pt nanostructures. A dye-sensitized solar cell comprising TiO2 covered with a heteroleptic RuII-type sensitizer (dye) and the semisolid triiodide/iodide ionic liquid electrolyte admixed with carbon-nanotube-supported Pt nanostructures yielded somewhat higher power conversion efficiencies (up to 7.9 % under standard reporting conditions) than those of the analogous Pt-free system. [ABSTRACT FROM AUTHOR]

Tungsten trioxide (WO3) is one of a few stable semiconductor materials liable to produce solar fuel by photoelectrochemical water splitting. To enhance its visible light conversion efficiency, we incorporated plasmonic gold nanoparticles (Au NPs) derivatized with polyoxometalate (H3PMo12O40) species into WO3. The combined plasmonic and catalytic effect of Au NPs anchored to the WO3 surface resulted in a large increase of water photooxidation currents. Shielding the Au NPs with polyoxometalates appears to be an effective means to avoid formation of recombination centers at the photoanode surface. [ABSTRACT FROM AUTHOR]

A multifunctional mediating system for bioelectrocatalytic oxidation of glucose is described. It comprises a conducting polymer, poly(3,4-ethylenodioxythiophene), carbon nanotubes modified with 4-(pyrrole-1-yl) benzoic acid that provide carboxyl groups that aid immobilization of glucose oxidase in a conductive three-dimensional network, tetrathiafulvalene that mediates electron exchange with the enzyme. This composite produces a system that is capable of effective oxidation of glucose to gluconic acid at pH 7. The current is concentration dependent to at least 60 mM and maintains 77 % of initial response for 35 days. Data supporting the utility of this system for electrochemical sensing and biofuel cell technology are presented. [ABSTRACT FROM AUTHOR]