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A conductive spinel CuFe2O4 is used to protect the metallic interconnect of solid oxide fuel cells (SOFCs) from oxidation and prevent the cathode from chromium poisoning. It is coated by the sol-gel method on a typical metallic interconnect material of Fe-16Cr alloy and evaluated by oxidation at 800degC for 200 h in air (the cathode atmosphere) under an applied current of 0.5 A cm[?]2. The results show that the coating is promising in providing oxidation resistance, and the oxide scale formed on both the positive and negative sides of the substrate are similar, which consists of a thin inner layer of Cr2O3, a middle layer of Cu-doped MnCr2O4 and a top layer of Fe2O3 with an overall thickness around 2 um and grows less than 0.5 um during the 200 h oxidation. The extrapolated area specific resistance (ASR) of the oxide scale at 800degC is approximately one seventh that formed on the uncoated Fe-16Cr alloy, suggesting that the outward migration of cations from the alloy substrate to the oxide scale is driven by the gradient of chemical potential rather than that of electrical potential in this particular situation due to the relatively high scale conductivity.

A solid oxide cell (SOC) integrating solid oxide fuel cell (SOFC) and solid oxide electrolysis cell (SOEC) usually utilizes two different materials as the anode and cathode prepared by the costly multi-elements co-doping process. In this work, LaCo0.6Ni0.4O3−δ(LCN) is employed as the contact material and the electrode for the symmetrical SOC and exhibits good catalytic activities towards the four typical reactions, i.e., oxygen reduction reaction (ORR), hydrogen oxidation reaction (HOR), oxygen evolution reaction (OER), and CO2reduction reaction (CO2RR). The LCN-GDC electrode has the low activation energies of 1.18 and 0.55 eV as the cathode and anode of SOFC, respectively. High peak power densities (PPDs) of 1.896 and 0.562 W cm−2are obtained at 800 °C for the Ni-YSZ (8 mol.% Y2O3stabilized ZrO2) anode-supported and YSZ (200 μm)-supported symmetrical SOFCs, respectively. An electrolysis current density (ECD) of 2.316 A cm−2is obtained at 800 °C and 2.0 V and a robust operation for over 120 h with a degradation rate of about 0.5 mV h−1is achieved with LCN as the current collector in air side at 750 °C for the symmetrical SOECs. Such a multi-functional material shows attractive competitiveness and successfully achieves fivefold applications in SOCs. The protocol described herein affords a new vision towards material development basing on the consideration of enhancing the chemical compatibility and lowering the cost of the whole SOC but not just one electrode.

New approach to activating carbon active sites to facilitate the electroconversion of CO2through N-vacancy engineering is proposed and confirmed by the density functional theory calculations and experimental results. N-vacancy engineered graphitic C3N4(g-C3N4) is identified as an efficient electrocatalyst to boost CH4formation owing to the three-coordinating to two-coordinating transition of the carbon atoms that surround N vacancies. The defected g-C3N4(DCN) exhibits a 44% faradaic efficiency with a CH4partial current density of 14.8 mA/cm2at −1.27 VRHEin 0.5 M KHCO3electrolyte, exceeding all the reported carbon-based materials and even being comparative to Cu-based electrocatalysts. Creation of more unsaturated carbon atoms enables the harmonic energy overlap near band gap edge between DCN and *CO, accounting for an improved strength of *CO on DCN, a lower energy barrier and an enhanced CO2RR to form CH4. This strategy holds the promise for tuning atomic configuration to enhance activity of catalyst.

A conductive spinel CuFe2O4is used to protect the metallic interconnect of solid oxide fuel cells (SOFCs) from oxidation and prevent the cathode from chromium poisoning. It is coated by the sol-gel method on a typical metallic interconnect material of Fe-16Cr alloy and evaluated by oxidation at 800°C for 200 h in air (the cathode atmosphere) under an applied current of 0.5 A cm−2. The results show that the coating is promising in providing oxidation resistance, and the oxide scale formed on both the positive and negative sides of the substrate are similar, which consists of a thin inner layer of Cr2O3, a middle layer of Cu-doped MnCr2O4and a top layer of Fe2O3with an overall thickness around 2 μm and grows less than 0.5 μm during the 200 h oxidation. The extrapolated area specific resistance (ASR) of the oxide scale at 800°C is approximately one seventh that formed on the uncoated Fe-16Cr alloy, suggesting that the outward migration of cations from the alloy substrate to the oxide scale is driven by the gradient of chemical potential rather than that of electrical potential in this particular situation due to the relatively high scale conductivity.