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As a cathode material for proton-conducting SOFCs (H–SOFCs), a novel MnCo 1.9 Sb 0.1 O 4 (MCSO) spinel material was suggested. The MCSO material was effectively produced, and it demonstrated excellent phase stability at elevated temperatures and chemical stability against CO 2 and H 2 O. Doping Sb into the MnCo 2 O 4 (MCO) allowed for enhanced proton diffusion and surface exchange, as evidenced by electrical conductivity relaxation tests. In addition, an oxygen-vacancy-rich surface was developed for the MCSO material, resulting in the possibility of a high cathode oxygen reduction reaction activity. The MCSO material was examined in the H–SOFC application, and the fuel cell with an MCSO cathode attained a high power density of 1380 mW cm−2 at 700 °C. At 700 °C, the cell employing the Sb-free MCO cathode, which had a comparable cell microstructure to the MCSO cell, only obtained a peak power density of 836 mW cm−2. The higher cell performance resulted from the Sb-modified MCO cathode's increased catalytic activity. In addition, the MCSO cell displayed excellent operational stability under fuel cell operating conditions, indicating that MCSO is a novel and effective spinel cathode for H–SOFCs. • A new MnCo 1.9 Sb 0.1 O 4 (MCSO) spinel was proposed for H–SOFCs. • Doping Sb into MnCo 2 O 4 (MCO) enhanced proton diffusion and surface exchange. • MCSO improved the cathode activity compared with Sb-free MCO. • A high performance was obtained for the fuel cell using MCSO cathode. [ABSTRACT FROM AUTHOR]

Zn0.58Co2.42O4 (ZCO), which is a novel spinel oxide, has been proposed as a cathode material for proton-conducting solid oxide fuel cells (H-SOFCs) to explore the possibility of using spinel oxide cathodes for H-SOFCs. The high oxygen-ion and proton migration kinetics of ZCO, which first-principles calculations and experiments have demonstrated, allow the ZCO cell to show high cell performance without impairing the stability of the material. Further optimizing the cathode/electrolyte interface, by utilizing the relatively low melting point of ZCO, allows a record-high performance to be obtained for the ZCO cell compared with other SOFCs using a spinel oxide cathode. [ABSTRACT FROM AUTHOR]

Copper foams deposited under various conditions are characterized in an airtight three‐electrode H‐cell system. Compared with the smooth copper electrode, the current density obtained on the porous copper electrodes is significantly improved. Using porous copper obtained from 0.2 M CuSO4 and 1.5 M H2SO4 electrolyte with 3 Acm−2 for 30s, the CO2 reduction current density is 27 mAcm−2 at a potential of −0.97 V vs RHE in 0.5 M KHCO3 electrolyte (with CO2 supplied at the flow rate of 15 sccm), tripling that of the smooth copper electrode (8 mAcm−2). The average pore size of the porous copper can be reduced by adding Hexadecyltrimethylammonium bromide (CTAB) in a small amount. Besides, the preferred orientation of crystal faces changed, which may influence the selectivity of the carbon dioxide reduction product. In the flow‐cell test, at constant current 10 mAcm−2, the CO production rate of porous copper with CTAB additive reached 11.91μmolh−1cm−2 and maintained a value more than 8.95 μmolh−1cm−2 during one‐hour electrolysis, which is much higher than smooth copper, 1.38 μmolh−1cm−2. [ABSTRACT FROM AUTHOR]

Electrochemical CO 2 reduction reaction (CO 2 RR) technology can reduce CO 2 emission with converting excess electrical energy to high-value-added chemicals, which however needs further improvement on the electrolyser cell performance. In this work, extensive factors were explored in continuous CO 2 electrolysers. Gold, one of the benchmark materials for CO 2 RR to produce CO, was used as the catalyst. Electrolyser configurations and membrane types have significant influences on cell performance. Compact MEA-constructed gas-phase electrolyser showed better catalytic performance and lower energy consumption. The gas diffusion electrode with a 7:1 mass ratio of total-catalyst-to-polytetrafluoroethylene (PTFE) ionomer exhibited the best performance. At a low total cell voltage of 2.2 V, the partial current density of CO production achieved 196.8 mA cm -2 , with 90.6% current efficiency and 60.4% energy efficiency for CO producing respectively. Higher CO selectivity can be achieved using anion exchange membranes, while higher selectivity for hydrogen and formate products can be achieved with cation exchange membranes. This research has pointed out a way on how to improve the CO 2 RR catalytic performance in flow cells, leaving aside the characteristics of the catalyst itself.