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The rapid development of machine learning has provided low‐cost and high‐throughput molecular energy prediction methods; however, the direct energy prediction of transition states (TSs) in radical reactions has received little attention, which can facilitate the rapid construction of potential energy surface (PES) and chemical reactivity inference. Here, we present a generic descriptor of TSs, molecules and radicals to realize the simultaneous prediction of their enthalpy of formation through the augmented molecular graph convolutional network (MGCN). It is proved that the network can rapidly (within milliseconds per prediction) and accurately predict the enthalpy of various types of samples, of which the mean absolute error (MAE) of the held‐out test set is 1.44 kcal/mol (>50% samples less than 1.0 kcal/mol) with high R2 (0.925–0.998) among all categories. The PES constructed from predictions is close to the calculated results by density functional theory (DFT) and conforms to the trend of chemical reactivity. [ABSTRACT FROM AUTHOR]

Subnanometric metal clusters have attracted extensive attention because of their unique properties as heterogeneous catalysts. However, it is challenging to obtain uniformly distributed metal clusters under synthesis and reaction conditions. Herein, we report a template‐guidance protocol to synthesize subnanometric metal clusters uniformly encapsulated in beta‐zeolite, with the metal ions anchored to the internal channels of the zeolite template via electrostatic interactions. Pt metal clusters with a narrow size range of 0.89 to 1.22 nm have been obtained on the intersectional sites of beta‐zeolite (Pt@beta) with a broad range of Si/Al molar ratios (15–200). The uniformly distributed Pt clusters in Pt@H‐beta are subject to strong electron withdrawal by the zeolite, which promotes transfer of active hydrogen, providing excellent activity and stability in hydrodeoxygenation reactions. A general strategy is thus proposed for the encapsulation of subnanometric metal clusters in zeolites with high thermal stability. [ABSTRACT FROM AUTHOR]

Propane dehydrogenation (PDH) is one of the most effective methods to produce propylene. But the industrial Pt‐based catalysts often suffer from short‐term stability under the high temperature reaction environment (500–700°C) via sintering and coke deposition. Herein, stable PDH reaction in high propylene yield has been achieved by the confinement of Pt–Zn intermetallic alloys (IMAs) in the channels of silicalite‐1. Single‐site Zn in the MFI framework was found to play a key role on assisting and stabilizing the PtZn IMAs for efficient PDH. By the cooperative action of the spatial confined PtZn IMAs and the lattice confined framework Zn, high propylene selectivity (>99%) without obvious deactivation was realized on the as‐developed catalyst (PtZn@S‐1) under 600°C even after 90 h. The low deactivation constant (0.003 h−1) was 6 times lower than that of the industrial PtSn catalyst. [ABSTRACT FROM AUTHOR]

Multimetallic nanocatalysts have attracted increasing attention for steam reforming owing to highly exposed active sites, but often suffering from severe sintering. Herein, we design subnanometric Ni‐Pt bimetal clusters (ca. 1.7 nm) encapsulated in Silicalite‐1 zeolite (2Ni0.5Pt@S‐1) through ligand‐stabilized method to prevent sintering by fixing the metal into microporous channels. In the steam reforming of n‐dodecane test, 2Ni0.5Pt@S‐1 gave an excellent activity and stability with a decrease of conversion only 4% at 600°C for 4 hr, which was about a quarter that of 2Ni0.5Pt/S‐1 synthesized by co‐impregnation method, ascribing to superior sinter‐resistance of encapsulation structure. Moreover, 2Ni0.5Pt@S‐1 exhibited a higher H2 selectivity up to 69.9% than that of 2Ni0.5Pt/S‐1 (64.4%), owing to suppressed methanation reaction based on subnanometric clusters. Shape‐selective steam reforming of n‐dodecane and ofm‐xylene was also observed, because of m‐xylene could hardly diffuse into the zeolite channels due to its bulky molecular size, further preventing potential deactivation by tars in reforming process. [ABSTRACT FROM AUTHOR]

Significance: Nanosheet HZSM‐5 film vertically grown on the substrate with the tailorable macro‐ and meso‐pores between the layers of nanosheets is hydrothermally synthesized by seed‐assisted secondary growth method. The as‐prepared nanosheet HZSM‐5 film exhibits reaction rate enhancement up to 312% in catalytic cracking of n‐dodecane as well as twice light olefins selectivity, ascribed to the better mass transfer of reactants in the hierarchical porous structure and the ultra‐thin b‐axis pores of nanosheets. © 2018 American Institute of Chemical Engineers AIChE J, 64: 1923–1927, 2018 [ABSTRACT FROM AUTHOR]