The Nb-doped lanthanum strontium ferrite perovskite oxide La Sr Fe Nb O (LSFNb) is evaluated as an anode material in a solid oxide fuel cell (SOFC). The effects of Nb partial substitution in the crystal structure, the electrical conductivity, and the valence of Fe ions are studied. LSFNb exhibits good structural stability in a severe reducing atmosphere at 800 °C, suggesting that high-valent Nb can effectively promote the stability of the lattice structure. The concentration of Fe increases after Nb doping, as confirmed by X-ray photoelectron spectroscopy. The maximum power density of a thick Sc-stabilized zirconia (ScSZ) electrolyte-supported single cell reached 241.6 mW cm at 800 °C with H as fuel. The cell exhibited excellent stability for 100 h continuous operation without detectable degeneration. Scanning electron microscopy clearly revealed exsolution on the LSFNb surface after operation. Meanwhile, LSFNb particles agglomerated significantly during long-term stability testing. Impedance spectra suggested that both the LSFNb anode and the (La Sr ) MnO /ScSZ cathode underwent an activation process during long-term testing, through which the charge transfer ability increased significantly. Meanwhile, low-frequency resistance (R ) mainly attributed to the anode (80 %) significantly increased, probably due to the agglomeration of LSFNb particles. The LSFNb anode exhibits excellent anti-sulfuring poisoning ability and redox stability. These results demonstrate that LSFNb is a promising anode material for SOFCs.

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To investigate the effect of heterogeneous nucleation sites on the anti-icing performance of superhydrophobic surfaces, the superhydrophobic POSS/PDMS coatings were prepared and covered by PVA through spraying coating method. The surface morphology was characterized by SEM, and the anti-icing performance of surfaces was characterized through contact angle, freezing temperature of surface water droplet and ice adhesion. The results show that with the optimum match of the particle distance and PVA spraying times, the PVA-POSS/PDMS coating has better anti-icing performance than superhydrophobic POSS/ PDMS coating: the freezing temperature of droplet on PVA-POSS/PDMS coating surface is −22.55°C, approximately 2°C lower than POSS/PDMS coating surface. This work confirms the adverse effect of heterogeneous nucleation sites and successfully improves the anti-icing performance of superhydrophobic surface by covering the heterogeneous nucleation sites with nucleation inhibitor. The synergism of nucleation inhibitor and the micro-nano structures is proposed, which will be conducive to the design of high-performance anti-icing materials.

A polymer “bridge” was designed to connect graphene oxide and poly(ether ether ketone), making stronger and tougher composites.

The low performance and insufficient catalytic activity of perovskite anodes hinder their further application in intermediate-temperature solid-oxide fuel cells (IT-SOFCs). A novel La Sr Fe Nb Pd O (LSFNP) anode material has been developed with Fe-Pd co-exsolutions for IT-SOFCs. Fe and Pd metallic nanoparticles are confirmed to exsolve on the surface of the perovskite anode during operation under a hydrogen atmosphere. The introduced Pd exsolutions promote the charge-transfer process slightly and the H -adsorption ability of the La Sr Fe Nb O (LSFN) parent anode significantly, as metallic Pd is a conductor with excellent catalytic activity and an absorber of hydrogen that can absorb a large amount of H by forming unstable chemical bonds. A single cell with the LSFNP anode exhibits high output performance (maximum power density of 287.6 mW cm at T=800 °C by using humidified H as the fuel), excellent redox stability, and considerable coking and sulfur tolerances. After the introduction of Pd exsolutions, the increase in the electrochemical performance is more significant under low H concentrations and at low temperatures with a maximum power density ratio of the LSFNP anode cell/LSFN anode cell reaching 18 under 5 % H /argon at T=650 °C. Pd-decorated LSFNP is a high-performance, redox-stable, coking-tolerant, and sulfur-tolerant anode material for IT-SOFCs, making Pd exsolution a reliable nanodecoration strategy to improve the low kinetics of perovskite anodes.