We have examined the use of Cu-Ni alloys as anodes for the direct oxidation of methane in solid-oxide fuel cells (SOFC) at 1073 K. Ceramic-metal (cermet) composites having alloy compositions of 0, 10, 20, 50 and 100% Ni were exposed to dry methane at 1073 K for 1.5 h to demonstrate that carbon formation is greatly suppressed on the Cu-Ni alloys compared to that of pure Ni. Increased reduction temperatures also reduced the carbon formation on the alloys. The performance of a fuel cell made with a Cu(80%)-Ni(20%) cermet was tested in dry methane for 500 h and showed a significant increase in power density with time. Impedance spectra of similar fuel cells suggest that small carbon deposits are formed with time and that the increase in performance is due to enhanced electronic conductivity in the anode. Finally, the implications of the use of metal alloys for SOFC applications are discussed. © 2002 The Electrochemical Society. All rights reserved.

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In this study, we report on how different impregnation procedures affect the distribution and morphology of the Cu component in Cu/CeO 2 /YSZ composite anodes and how this affects anode performance. Two different methods for Cu addition to the porous YSZ anode were investigated: impregnation using aqueous solutions of Cu(NO 3 ) 2 and impregnation using aqueous solutions of Cu(NO 3 ) 2 plus urea. The latter method produced a homogeneous distribution of Cu throughout the anode while the former resulted in a higher concentration of Cu near the exposed surface relative to that in the bulk. Studies of the thermal stability of the deposited copper layers, and the influence of the Cu distribution on cell performance when operating with humidified H 2 as the fuel are also presented. AbstractIn this study we report on how different impregnation procedures affect the distribution and morphology of the Cu component in Cu/CeO 2 /YSZ composite anodes and how this affects anode performance. Two different methods for Cu addition to the porous YSZ anode were investigated: impregnation using aqueous solutions of Cu(NO 3 ) 2 and impregnation using aqueous solutions of Cu(NO 3 ) 2 plus urea. The latter method produced a homogeneous distribution of Cu throughout the anode while the former resulted in a higher concentration of Cu near the exposed surface relative to that in the bulk. Studies of the thermal stability of the deposited copper layers, and the influence of the Cu distribution on cell performance when operating with humidified H 2 as the fuel are also presented.

A variety of substituted benzisoxazolines have been synthesized by the [3 + 2] cycloaddition of nitrones and arynes. The reaction scope is broad, the reaction conditions are mild, and the process tolerates a variety of functional groups.

To improve the LSM-YSZ cathode performance of intermediate temperature Consideration of a simplified TPB (triple phase boundary) reaction geometry indicates that the enhancement may be attributed to the high electrocatalytic activity of SSC for electrochemical reduction of oxygen in a region that can be located a small distance away from the strict triple phase boundaries. The implication of this work for developing high-performance electrodes is also discussed.

The palladium-catalyzed annulation of arynes by substituted o-halobenzamides produces N-substituted phenanthridinones in good yields. This methodology provides this important heterocyclic ring system in a single step by simultaneous C-C and C-N bond formation, under relatively mild reaction conditions, and tolerates a variety of functional groups.

Exploiting highly active and bifunctional catalysts for both hydrogen evolution reaction (HER) and hydrazine oxidation reaction (HzOR) is a prerequisite for the hydrogen acquisition. High‐entropy materials have received widespread attention in catalysis, but the high‐performance bifunctional electrodes are still lacking. Herein, a novel P‐modified amorphous high‐entropy CoFeNiCrMn compound is developed on nickel foam (NF) by one‐step electrodeposition strategy. The achieved CoFeNiCrMnP/NF delivers remarkable HER and HzOR performance, where the overpotentials as low as 51 and 268 mV are realized at 100 mA cm−2. The improved cell voltage of 91 mV is further demonstrated at 100 mA cm−2 by assessing CoFeNiCrMnP/NF in the constructed hydrazine‐assisted water electrolyser, which is almost 1.54 V lower than the HER||OER system. Experimental results confirm the important role of each element in regulating the bifuncational performance of high‐entropy catalysts. The main influencing elements seem to be Fe and Ni for HER, while the P‐modification and Cr metal may contribute a lot for HzOR. These synergistic advantages help to lower the energy barriers and improve the reaction kinetics, resulting in the excellent bifunctional activity of the CoFeNiCrMnP/NF. The work offers a feasible strategy to develop self‐supporting electrode with high‐entropy materials for overall water splitting.

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