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Despite significant research efforts, designing bimetallic catalysts rationally remains a challenging task. Herein, we combine the strengths of high-throughput experiments and DFT calculations synergistically to design new core-shell bimetallic catalysts. The total oxidation of propane is used as a probe, proof-of-concept reaction. The methodology is successful in designing three bimetallic catalysts. Of these catalysts, AgPd is cheaper, more active than the existing most active single-metal catalyst (Pt), and stable under the reaction conditions. Extended X-ray absorption fine structure characterization confirms the formation of a bimetallic alloy. This study provides a path forward for designing bimetallic catalysts rationally for vapor phase metal-catalyzed reactions. [ABSTRACT FROM AUTHOR]

Volcano curves for hydrocarbon total oxidation. • The use of the volcano curve to predict catalysts for an entire homologous series is exploited. • Catalytic activity over seven monometallic and three Ag-Pd/Al 2 O 3 bimetallic catalysts is evaluated experimentally. • Hysteresis in activity, with three distinct kinetic regimes, with varying oxygen concentration is found. • Hydrocarbons with two or more carbon atoms are good surrogates of the alkane homologous series whereas methane is not. • The feed composition controls the catalyst oxidation state and potentially impacts the optimal catalyst properties. Volcano curves are typically developed and used for predicting new catalysts for a single reaction and one substrate. The concept of using the volcano curve to predict catalysts for an entire homologous series of reactions has been unexplored. Herein the catalytic activity of seven monometallic catalysts (Pt, Pd, Rh, Ag, Ni, Cu, and Co/Al 2 O 3) and three Ag-Pd/Al 2 O 3 bimetallic catalysts is evaluated in the total oxidation of small alkanes (methane, ethane, propane, and isobutane) in the 280–400 °C temperature range under fuel lean and rich conditions. We show that hysteresis in activity, with three distinct kinetic regimes, is a common phenomenon of alkane oxidation over all catalysts studied when varying the oxygen concentration, and the size of the hysteresis loop depends on the oxophilicity of the catalyst and the reducing ability of the hydrocarbon. Expectedly, the concept of the universality of the volcano curve for a homologous series is valid but only when a suitable surrogate substrate is chosen. Hydrocarbons with two or more carbon atoms can serve as surrogates of the alkane homologous series, whereas methane is not. Interestingly and consistent with the hysteresis, the feed composition controls the catalyst oxidation state and potentially impacts the optimal catalyst descriptors used to determine new catalysts. The predicted 1:3 Ag-Pd catalyst is indeed superior to single metals for the homologous series under fuel lean conditions for ethane and larger alkanes. It is inferior to Pt under fuel rich conditions and better than Pd and Pt for methane rich conditions. A method for qualitative inference of the catalyst structure, based on the volcano curve and the oxidation state of the catalyst, is proposed. [ABSTRACT FROM AUTHOR]

Bimetallic catalyst design: where brain meets brawn The cover picture represents a methodology to design bimetallic catalysts by synergistically combining high‐throughput experiments and quantum mechanical calculations. A robotic arm is used to represent the high‐throughput experimentation system. In their Full Paper on p. 3712 ff., N. R. Peela et al. demonstrate the details of the methodology. Ag‐Pd bimetallic catalysts are found to be the best catalysts for the propane total oxidation reaction. Owing to its generic nature, the methodology can be used for designing catalysts for any vapor‐phase metal‐catalyzed reaction. This artwork was created by using images from Presenter Media. [ABSTRACT FROM AUTHOR]

Selective hydrodeoxygenation (HDO) of 5-hydroxymethylfurfural to 2,5-dimethylfuran is of great importance. We reveal a simple pathway for green and efficient HDO using readily available copper with in-situ hydrogen generation. A highly dispersed Cu/PBSAC catalyst consisting of small metallic Cu0 nanoparticles carries out isopropyl alcohol (IPA) dehydrogenation and subsequent HDO of HMF. Density functional theory calculations reveal that the dehydrogenation of IPA is more favorable on Cu(211) with a lower energy barrier of ~0.6 eV. This facet exists in a higher ratio on nanosized catalysts. Batch reactions using Cu/PBSAC at 190 °C exhibited 91.9% HMF conversion and 71.7% DMF selectivity in 6 hr, and > 96% DMF yield in 10 hr. The mechanical strength of the carbon support is ideal for continuous processing for increased productivity; we demonstrate a > 90% DMF yield at 1/WHSV of 2.4 hr. The process demonstrated here can be integrated with upstream HMF separation utilizing carbon adsorbents. [Display omitted] • Nanosized copper is an excellent catalyst for HMF HDO and IPA dehydrogenation. • Earth abundant metal and in situ hydrogen generation are ideal for the industry. • Metal size effect on reactivity improvement is explained by simulations. • Cu(211) is crucial active site; more exists on small particles. • The catalyst is suitable for continuous processing, showcasing high 92% DMF yield. [ABSTRACT FROM AUTHOR]