Small olefins from syngas: The conversion of coal or natural gas to liquid fuels or chemicals often proceeds through the production of CO and H ₂ . This mixture, known as syngas, is then converted to hydrocarbons with Fischer-Tropsch catalysts. For the light olefins (ethylene to butylenes) needed for chemical and polymer synthesis, conventional catalysts are mechanistically limited to <60% conversion and deactivate through carbon buildup. Jiao et al. developed a bifunctional catalyst that achieves higher conversions and avoids deactivation (see the Perspective by de Jong). A zinc-chromium oxide creates ketene intermediates that are then coupled over a zeolite. Science , this issue p. 1065 , see also p. 1030

Large single-crystal graphene is highly desired and important for the applications of graphene in electronics, as grain boundaries between graphene grains markedly degrade its quality and properties. Here we report the growth of millimetre-sized hexagonal single-crystal graphene and graphene films joined from such grains on Pt by ambient-pressure chemical vapour deposition. We report a bubbling method to transfer these single graphene grains and graphene films to arbitrary substrate, which is nondestructive not only to graphene, but also to the Pt substrates. The Pt substrates can be repeatedly used for graphene growth. The graphene shows high crystal quality with the reported lowest wrinkle height of 0.8 nm and a carrier mobility of greater than 7,100 cm² V⁻¹ s⁻¹ under ambient conditions. The repeatable growth of graphene with large single-crystal grains on Pt and its nondestructive transfer may enable various applications.

Catalysis at the Edge: Many catalysts in solution, such as metalloenzymes and homogeneous metal complexes, create active sites where the metal ion is available to bind and activate reactants. Such coordinately unsaturated ferrous sites, or CUFs, have been created in a supported heterogeneous catalyst by Fu et al. (p. 1141 ). Ferrous oxide islands grown on platinum single-crystal surfaces were much more reactive for CO oxidation at low temperatures than more oxidized ferric islands. This difference arose from sites at the interface between the islands and the Pt surface that activated oxygen. Silica-supported Pt-Fe catalysts were active for CO removal from hydrogen streams, a reaction critical for maintaining the activity of fuel cells.