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Solid oxide electrolysis cells (SOECs) have captured worldwide attention as a promising energy conversion device, but durability at large current densities is still an issue. Here, the authors present an encouraging stable anode design for electrolysis at high current densities, in which a nano La0.6Sr0.4CoO3−δ (LSC) catalyst network is integrated with robust microchannels of the yttria-stabilized zirconia scaffold. Such a controlled structured electrode not only allows rapid gas diffusion, but also provides sufficient active sites as well as firm anode–electrolyte interface adhesion for achieving highly stable and efficient electrolysis. These unique advantages lead to an extremely low polarization resistance of 0.010 Ω cm2 and high durability for over 100 h at a large current density of 3.4 A cm−2 at 800 °C. The outstanding performance demonstrates that the as-prepared cell structure may be generally applicable in the design of high-efficiency energy conversion systems. [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]

Tailoring electrode–electrolyte interphases could potentially enhance the interfacial reaction for protonic ceramic fuel cells (PCFCs), and an in situ generated dense active cathode functional interlayer (CFI) via a low-cost linear current sweeping (LCS) method is developed based on the perovskite-related Sm2Ba1.33Ce0.67Cu3O9 (SBCC) cathode material. Due to the simultaneous occurrence of Ba element segregation and the densifying process at the SBCC/BZCY interface during the LCS procedure, the Ba(Zr,Ce)1−x(Sm,Y,Cu)xO3−δ (BZCSYC) phase is formed and sandwiched between two SBCC phases in the 2 μm thick CFI, promoting the protolysis to the SBCC@BZCSYC CFI–cathode interface. When assessing the SBCC cathode accompanied by the CFI based on a BaZr0.1Ce0.7Y0.2O3−δ-based single-cell, exhilarating cell performance with peak power densities (PPDs) of 1669 and 905 mW cm−2, corresponding to the interfacial polarization resistance (RP) values of 0.027 and 0.115 Ω cm2 at 700 and 600 °C, respectively, is attained. The superior cell performance, including the remarkably high PPD and the notably low RP, clearly state that SBCC is a preferential cathode alternative. The LCS technique is an advanced method to optimize the electrode interface for high-performance low-temperature PCFCs. [ABSTRACT FROM AUTHOR]

Doping the La0.5Sr0.5MnO3−δ (LSM) cathode with the Co element allows the new material La0.5Sr0.5Mn0.9Co0.1O3−δ (LSMCo) to show improved performance compared with the Co-free LSM for proton-conducting solid oxide fuel cells (H-SOFCs), demonstrated by both experiments and first-principles calculations. More importantly, doping Co into LSM triggers the activity of the cathode/electrolyte interface in the composite cathode, leading to an impressively high fuel cell performance of the cell using the LSMCo composite cathode and also revealing the importance of the interfacial design for the cathode of H-SOFCs. [ABSTRACT FROM AUTHOR]

Doping a LaMnO3 cathode with the Ca element produces a La0.5Ca0.5MnO3−δ cathode, which shows high performance for proton-conducting solid oxide fuel cells, surpassing all similar cells, although the low basicity of Ca makes it an inappropriate doping element in traditional thinking. Furthermore, rather than compromising electrochemical performance for chemical stability, La0.5Ca0.5MnO3 also shows excellent chemical stability, making it promising for application in proton-conducting solid oxide fuel cells. [ABSTRACT FROM AUTHOR]

In the past decade, intensive research on proton-conducting oxide materials has provided a basis for the development of intermediate-temperature protonic ceramic electrochemical cells, which constitute a real alternative to conventional cells based on oxygen-conducting electrolytes. To achieve both high efficiency and excellent performance, not only electrolytes but also electrode materials should be carefully selected considering their functional properties. Compared to the traditional ABO3 perovskite electrode materials, Ln2NiO4+δ with a layered structure has unique advantages (high chemical stability, mechanical compatibility, improved oxygen transport, and hydration ability), and thus is now becoming a hot topic in this field, offering both scientific and practical interests. However, a comprehensive and in-depth review is still lacking in the literature to date. Accordingly, this work presents a comprehensive overview of the prospects of layered nickelates (Ln2NiO4+δ, where Ln = La, Nd, and Pr) as one of the most attractive oxygen (steam) electrode materials for protonic ceramic electrochemical cells. In particular, the crystalline features, defect structure, stability, chemical properties, and mechanical compatibility of this class of materials, contributing to their transport functionality, are discussed with the primary emphasis on revealing the relationship between the composition of the materials and their properties. The presented systematic results reveal the main strategies regarding the utilisation of Ln2NiO4+δ-based electrodes and existing gaps related to fundamental and applied research aspects. [ABSTRACT FROM AUTHOR]

Developing new low-cost high-performance cobalt-free cathode materials for low temperature proton-conducting solid oxide fuel cells (H-SOFCs) has been an imperative topic. In response to this challenge, we herein develop a novel in situ Pr diffusion strategy based on a Sm0.2Ce0.8O2−δ–Pr(Pr0.5Ba1.5)Cu3O7−δ (SDC–PBCu, 3 : 7 wt%) compound, to achieve a perovskite-related proton-blocking composite cathode (PBCC) Ce1−xPrxO2−δ–Ba2CeCu3O7.4–Sm2Ba1.33Ce0.67Cu3O9–CuO (PDC–BCC–SBCC–CuO) for BaZr0.1Ce0.7Y0.2O3−δ-based H-SOFCs. The single cell achieves a remarkable performance with a maximum power density (MPD) of 1000 and 566 mW cm−2, corresponding to the interfacial polarization resistance (RP) of 0.037 and 0.188 Ω cm2 at 700 and 600 °C, respectively. The XRD results demonstrate that the PBCu phase disappears after the calcination of the mixed SDC–PBCu composite powder at 900 °C, with the formation of four new phases including fluorite structured PDC, orthorhombic layered material BCC, tetragonal perovskite-related SBCC and a small quantity of metallic oxide CuO, being favorable for a superior cathode performance. The ascendant electrochemical performance including the very high MPD and the lower RP obtained here indicate that the quaternary cobalt-free PBCC PDC–BCC–SBCC–CuO is a preferable alternative for high-performance low-temperature H-SOFCs. [ABSTRACT FROM AUTHOR]

Intermediate temperature solid-oxide fuel cells (IT-SOFCs) ), as one of the energy conversion devices, have attracted worldwide interest for their great fuel efficiency, low air pollution, much reduced cost and excellent longtime stability. In the intermediate temperature range (500–700 °C), SOFCs based on proton conducting electrolytes (PSOFCs) display unique advantages over those based on oxygen ion conducting electrolytes. A key obstacle to the practical operation of past P-SOFCs is the poor stability of the traditionally used composite cathode materials in the steam-containing atmosphere and their low contribution to proton conduction. Here we report the identification of a new Ruddlesden–Popper-type oxide Sr3Fe2O7−δ that meets the requirements for much improved long-term stability and shows a superior single-cell performance. With a Sr3Fe2O7−δ-5 wt% BaZr0.3Ce0.5Y0.2O3−δ cathode, the P-SOFC exhibits high power densities (683 and 583 mW cm−2 at 700 °C and 650 °C, respectively) when operated with humidified hydrogen as the fuel and air as the cathode gas. More importantly, no decay in discharging was observed within a 100 hour test. [ABSTRACT FROM AUTHOR]

A proton-conducting solid oxide electrolysis cell using an Y-doped BaZrO3 electrolyte film, which has been demonstrated to be chemically stable, was successfully fabricated for the first time and showed a promising electrolysis performance. [ABSTRACT FROM AUTHOR]

Multiple magnetite nano-cores@void@porous shell microspheres have been fabricated by using the algal cell wall as the hollow porous shell precursor and the intracellular substances as the reducing agents to form magnetite cores inside the microspheres via hydrothermal reactions. This method not only simplifies the fabricating steps and supersedes harmful chemical reagents, but also endows the microspheres with a uniform size (∼2.5 μm), porous shell (∼15 nm), multiple magnetite nano-cores (∼25 nm) and high void volume ratio (>70%). The product presents fast magnetic separation and redispersibility as well as pH-switched protein auto-loading (high capacity >600 mg g−1) and unloading as high performance delivery vehicles. [ABSTRACT FROM AUTHOR]