Engineering of Ruthenium-Iron Oxide Colloidal Heterostructures: Improved Yields in CO2 Hydrogenation to Hydrocarbons.

Catalytic CO2 reduction to fuels and chemicals is a major pursuit in reducing greenhouse gas emissions. One approach utilizes the reverse water-gas shift reaction, followed by Fischer-Tropsch synthesis, and iron is a well-known candidate for this process. Some attempts have been made to modify and improve its reactivity, but resulted in limited success. Now, using ruthenium-iron oxide colloidal heterodimers, close contact between the two phases promotes the reduction of iron oxide via a proximal hydrogen spillover effect, leading to the formation of ruthenium-iron core-shell structures active for the reaction at significantly lower temperatures than in bare iron catalysts. Furthermore, by engineering the iron oxide shell thickness, a fourfold increase in hydrocarbon yield is achieved compared to the heterodimers. This work shows how rational design of colloidal heterostructures can result in materials with significantly improved catalytic performance in CO2 conversion processes.

Transition-metal interdiffusion and solid electrolyte poisoning in all-solid-state batteries revealed by cryo-TEM.

Using scanning transmission electron microscopy, along with electron energy loss spectroscopy, under cryogenic conditions, we demonstrate transition-metal dissolution from a layered Ni-rich oxide cathode material and subsequent diffusion into the bulk of a lithium thiophosphate solid electrolyte during electrochemical cycling. This problem has previously only been considered for liquid-electrolyte-based batteries.