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The synthesis and electrochemical insertion of lithium into the Wadsley–Roth NaNb13O33 phase is studied. Lithium intercalation to form LixNaNb13O33 reaches a value of up to x~15, between 3.0 and 1.0 V vs. Li+/Li at a slow cycling rate, a capacity of 233 mAh g−1. Within this voltage window, two sharp peaks and one broad peak are observed in the differential capacity plots of lithium intercalation suggesting multiple two‐phase regions. High Li‐ion conductivity and rate capability was demonstrated. The lithium diffusion constant is about an order of magnitude greater than TiNb2O7. The average voltage is about 1.6 V and its high‐rate capability makes NaNb13O33 potentially useful as an anode in a fast‐charge Li‐ion battery application. [ABSTRACT FROM AUTHOR]

Different weight ratios of polyaniline (PANI) to poly (acrylic acid) (PAA) were synthesized as interpenetrating polymer networks and blended with sulfonated poly (ether ether ketone) (SPEEK). In‐situ polymerization was performed by chemical oxidation of aniline in the presence of PAA. The composites showed actuation capability in the presence of fuel/air and moisture. Mechanical testing indicated that samples with higher concentration of PAA were stronger. For instance, PANI1PAA2SPEEK3 breaks at 8.4 MPa and has a failure strain of 2.5%, which is higher than PANI3PAA1SPEEK3 at 7 MPa and 2%. However, higher amount of PAA resulted in a lower electrochemical conductivity of 1.52 × 10−2 S/cm for the former and 1.8 × 10−2 S/cm for the latter. Intermolecular interaction at the optimum composition is necessary to induce forward and reverse bending of catalyst coated composite under exposure of fuel and air. In addition, the formation of compact structures and rough surfaces resulted in the maximal contractile strain of 1% for PANI3PAA1SPEEK3 based on moisture actuation. [ABSTRACT FROM AUTHOR]

The viability of converting wood chips and plastic to power via compact integrated catalytic fast/slow pyrolysis, combustor, and Stirling engine technologies was determined using modeling analysis. Aspen simulations followed by sizing analysis were performed to determine the size, weight, and net energy efficiency of upgrading wood chips and plastic to power using a compact energy system with a feedstock processing capacity of 1 kg h−1. The equipment and tooling to fabricate individual components of a compact energy system were identified. The total costs of fabricating all the individual components of compact energy systems were assessed. A discounted cash flow analysis with an internal rate of return of 20% was used to assess the minimum selling price of compact energy systems. The specific energy (Wh kg−1) of the compact catalytic fast pyrolysis system, compact slow pyrolysis system, and compact plastic conversion system were assessed at 20, 29, and 63, respectively. The assessed capital and annual costs of manufacturing 10 000 compact energy systems per year were $51 million and about $11 to $13 million, respectively. The calculated minimum selling price of a catalytic fast pyrolysis system, a compact slow pyrolysis system, and a compact plastic conversion system were $3055, $3021, and $2980, respectively. The sensitivity analysis results showed that the internal rate of return, capital investment, materials cost, annual operating costs, and capital cost have significant impacts on the minimum selling price of compact energy systems. © 2021 Society of Chemical Industry and John Wiley & Sons, Ltd [ABSTRACT FROM AUTHOR]

Herein we report a method for the synthesis of 2‐aryl thiochromenones via a sulfuration of 2'‐chlorochalcones. The chalcones could be prepared in advance or in situ obtained from 2'‐chloroacetophenones and aromatic aldehydes. The conditions were tolerant of functionalities including chloro, fluoro, methylthio, phenoxy, and trifluoromethyl groups. 2‐Heteroaryl thiochromenones could also be obtained in moderate yields. Our method appears to be a simple, general tactic to afford 2‐aryl thiochromenones from commercial starting materials. [ABSTRACT FROM AUTHOR]

Ru@RuO2 core‐shell nanorods were successfully synthesized by heat‐treating Ru nanorods with air oxidation through an accurate control of the temperature and time. The structure, composition, dimension, and adsorption property of the core‐shell nanorods were well characterized with XRD and TEM. The catalytic activity and stability were electrochemically evaluated with a rotating disk electrode, a rotating ring‐disk electrode, and chronopotentiometric methods. The Ru@RuO2 nanorods reveal excellent bifunctional catalytic activity and robust stability for both oxygen evolution reaction (OER) and hydrogen evolution reaction (HER). The overpotentials for OER and HER are 320 mV and 137 mV at the current density of 10 mA cm−2, respectively. The catalytic activity of Ru@RuO2 nanorods for OER is 6.5 times higher than that of the state‐of‐the‐art catalyst IrO2 according to the catalytic current density measured at 1.60 V (versus RHE). The catalytic activity of Ru@RuO2 nanorods for HER is comparable to 40% Pt/C by comparing the catalytic current densities at −0.2 V. [ABSTRACT FROM AUTHOR]