Solid oxide fuel cells (SOFCs) are a rapidly emerging energy technology for a low carbon world, providing high efficiency, potential to use carbonaceous fuels, and compatibility with carbon capture and storage. However, current state-of-the-art materials have low tolerance to sulfur, a common contaminant of many fuels, and are vulnerable to deactivation due to carbon deposition when using carbon-containing compounds. In this review, we first study the theoretical basis behind carbon and sulfur poisoning, before examining the strategies toward carbon and sulfur tolerance used so far in the SOFC literature. We then study the more extensive relevant heterogeneous catalysis literature for strategies and materials which could be incorporated into carbon and sulfur tolerant fuel cells.

Nano-particle hydroxyapatite (HA) rods, were rapidly synthesised using a three pump continuous hydrothermal process (using a water feed at up to 400 degrees C and at 24 MPa): the product was obtained as a highly crystalline and phase pure material, without the need for an ageing step or subsequent heat treatment.

With their high temperatures and brittle ceramic components, solid oxide fuel cells (SOFCs) might not seem the obvious fit for a power source for transportation applications. However, over recent years advances in materials and cell design have begun to mitigate these issues, leading to the advantages of SOFCs such as fuel flexibility and high efficiency being exploited in vehicles. Here we review the advances in SOFC technology which have led to this, look at the vehicles that SOFCs have already been used in, and discuss the areas which need improvement for full commercial breakthrough, and the ways in which catalysis science can assist with these. In particular we identify lifetime and degradation, fuel flexibility, efficiency and power density for improvement, and areas of catalysis science ranging from surface science and computational materials design to improvements in reforming catalysts and reformer design as key to this. MainDecarbonising transport is one of the largest challenges in the global response to climate change. Globally, transport is responsible for 23% of emissions and currently relies on hydrocarbons for 92% of its energy 1 . Decarbonisation is particularly difficult for transportation, because one of the key requirements for the energy source is portability, and hydrocarbons are one of the most energy dense substances available. In addition, the public health burden from pollutants such as particulates, nitrogen oxides and sulfur oxides emitted by vehicles is large, so cleaner energy sources are required.Efforts in transportation have focussed on batteries and polymer electrolyte fuel cells (PEFCs) running on hydrogen, alongside efficiency improvements and fuel switching. Although over the last decade batteries have been the dominant technology because they have advantages over fuel cells in manufacturing, cost, responsiveness in a vehicle and availability of supporting infrastructure, in the longer-term fuel cells may have advantages in some areas. The clearest advantage of fuel cells is high energy density, where it's not known whether battery technology will ever advance far enough to power long-distance transportation such as ships or intercontinental flights. In the area of passenger vehicles, with high battery vehicle penetration, much of the local grid infrastructure such as substations may not be able to cope and may have to be replaced -it is not clear at the moment whether this will be more expensive and disruptive than the rollout of the hydrogen-fuelling network which would be needed to support fuel cell vehicles. In applications such as buses where fast charging/refuelling is needed, fuel cells also possess an innate advantage. Finally, the wider advantage of switching to a hydrogen-fuelled transportation system is that electrolysers can be used to smooth the intermittent supply from renewable energy, while at the same time producing hydrogen fuel for vehicles.One technology which was until relatively recently deemed unsuitable for transportation, but nevertheless has unique ad...

A series of crystalline homometallic and heterometallic cobalt and nickel hydroxides and oxides were prepared using a continuous hydrothermal flow synthesis system. In all syntheses, the relevant metal salt solutions were pumped under high pressure to meet pH or other chemical modifiers (H 2 O 2 or PVP) before the mixture was brought into contact with a feed of superheated (or supercritical) water, whereupon precipitation and particle growth occurred. The resulting nanoparticle (typically less than 100 nm in diameter) suspensions were collected from the outlet of the back-pressure regulator of the hydrothermal system. The collected suspensions were centrifuged, and the washed solids were freeze-dried prior to analyses. The nanopowders were characterized by a number of analytical methods including X-ray powder diffraction, Brunauer-Emmett-Teller (BET) surface area measurements, and simultaneous thermogravimetric analysis/differential scanning calorimetry.

A novel High-Throughput Continuous Hydrothermal (HiTCH) flow synthesis reactor was used to make directly and rapidly a 66-sample nanoparticle library (entire phase diagram) of nanocrystalline Ce(x)Zr(y)Y(z)O(2-delta) in less than 12 h. High resolution PXRD data were obtained for the entire heat-treated library (at 1000 degrees C/1 h) in less than a day using the new robotic beamline I11, located at Diamond Light Source (DLS). This allowed Rietveld-quality powder X-ray diffraction (PXRD) data collection of the entire 66-sample library in <1 day. Consequently, the authors rapidly mapped out phase behavior and sintering behaviors for the entire library. Out of the entire 66-sample heat-treated library, the PXRD data suggests that 43 possess the fluorite structure, of which 30 (out of 36) are ternary compositions. The speed, quantity and quality of data obtained by our new approach, offers an exciting new development which will allow structure-property relationships to be accessed for nanoceramics in much shorter time periods.

A flexible metal-organic framework selectively sorbs para- (pX) over meta-xylene (mX) by synergic restructuring around pX coupled with generation of unused void space upon mX loading. The nature of the structural change suggests more generally that flexible structures which are initially mismatched in terms of fit and capacity to the preferred guest are strong candidates for effective molecular separations.

A dense composite of silver and Ce0.8Sm0.2O2−δ (Ag-CSO) was manufactured from ceramic nanoparticles coated by electroless deposition of silver. At 700 °C, a 1-mm-thick membrane of the composite delivered an excellent oxygen permeation rate from air with a value of 0.04 μmol cm–2 s–1, using argon as the sweep gas and 0.17 μmol cm–2 s–1 using hydrogen. The low sintering temperature of the CSO nanoparticles allows the use of Ag rather than Pt or Pd and reduces the amount of metal needed for electronic conductivity to just 5.6 vol %, which is lower than any value reported in the literature. Oxygen diffusivity measurements confirmed that the oxygen migration remained high in the composite, with an increase in surface exchange coefficient of three orders of magnitude over Gd-doped ceria. The ease of membrane fabrication, combined with encouraging oxygen permeation rates, demonstrate the promise of the material for high-purity oxygen separation below 700 °C.

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