The micrometer-sized H-Nb2O5 could achieve fast lithium-ion storage by engineering its planar defects.

No abstract

BaHf0.1Ce0.7Yb0.2O3−δ proton-conducting electrolyte exhibits high conductivity, excellent ionic transference number, remarkable chemical stability, and great compatibility with NiO, as confirmed by experimental and computational results.

Proton-conducting reversible solid oxide cells (P-ReSOCs) are receiving increasing attention because they have potential to efficiently operate at intermediate temperatures to reduce cost and prolong operational life. Here we report our findings in the rational design of a new series of donor- and acceptor-codoped proton conductors through careful manipulation of defect chemistry. Specifically, BaNb­(Ta)0.05Ce0.7Yb0.25O3‑δ exhibits high ionic conductivity (0.012 S cm–1) while maintaining exceptional stability when exposed to Ar with 30% H2O at 500 °C for 500 h. In contrast, the resistance of BaZr0.1Ce0.7Y0.1Yb0.1O3‑δ increases continuously with time under the same condition due to reaction with H2O, as rationalized using density functional theory (DFT)-based computations. In addition, single cells based on BaNb0.05Ce0.7Yb0.25O3‑δ achieve a high peak power density of 1.12 W cm–2 in the fuel cell mode and a high current density of 2.24 A cm–2 at 1.3 V in the electrolysis mode at 600 °C. Overall, this work provides new insights for the development of highly conductive and stable proton conductors for P-ReSOCs.

Solid oxide fuel cells (SOFCs) are a promising solution to a sustainable energy future. However, cell performance and stability remain a challenge. Durable, nanostructured electrodes fabricated via a simple, cost-effective method are an effective way to address these problems. In this work, both the nanostructured PrBa0.5Sr0.5Co1.5Fe0.5O5+δ (PBSCF) cathode and Ni–Ce0.8Sm0.2O1.9 (SDC) anode are fabricated on a porous yttria-stabilized zirconia (YSZ) backbone via solution infiltration. Symmetrical cells with a configuration of PBSCF|YSZ|PBSCF show a low interfacial polarization resistance of 0.03 Ω cm2 with minimal degradation at 700 °C for 600 h. Ni-SDC|YSZ|PBSCF single cells exhibit a peak power density of 0.62 W cm–2 at 650 °C operated on H2 with good thermal cycling stability for 110 h. Single cells also show excellent coking tolerance with stable operation on CH4 for over 120 h. This work offers a promising pathway toward the development of high-performance and durable SOFCs to be powered by natural gas.