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This mini-review summarizes the use of operando spectroscopy to investigate the dynamic structure of heterogeneous catalysts under working conditions. Following the background to the development of operando spectroscopy, we briefly reviewed the latest highlight on this subject. Then, two challenging but attention-grabbing techniques, that is operando techniques under the harsh conditions and the integration of operando techniques in a unit cell, were introduced. Likely, operando techniques open up new vistas to explore reaction mechanisms and help us design the next generation industrial catalysts. Current Opinion in Chemical Engineering 2016, 12 :1–7 This review comes from a themed issue on Nanotechnology Edited by Hong Yang and Hua Chun Zeng For a complete overview see the Issue and the Editorial Available online 4th February 2016 http://dx.doi.org/10.1016/j.coche.2016.01.004 2211-3398/© 2016 Elsevier Ltd. All rights reserved. [ABSTRACT FROM AUTHOR]

[Display omitted] • The SMSI strength is adjusted by varying the pretreatment gas. • A more pronounced SMSI strength results in higher electron density of Pt. • The defective TiO x promotes C–H activation for enhancing activity. • Catalysts with stronger SMSI show better propane dehydrogenation performance. The strong metal-support interaction exerts a significant influence on the catalytic performance of the metal active site. This paper describes the modulation of the coverage of TiO x on the Pt nanoparticles via the pretreatment atmosphere, and its influence of the catalytic performance for propane dehydrogenation. The direct reduction in H 2 at 600 °C of the Pt/TiO 2 -Al 2 O 3 catalyst induces partial coverage of the Pt nanoparticles by TiO x. This partial coverage with TiO x leads to higher electron density over platinum than catalysts treated through air calcination followed by reduction, which can enhance the selectivity of propylene. Furthermore, the presence of TiO x in the catalysts can promote C–H activation during propane dehydrogenation. Eventually, this synergistic catalyst presents a high formation rate of propylene (141.1 mmol·g cat -1·h−1) and propylene selectivity of ∼ 91 % with a low deactivation rate of 0.09 h−1. This study unveils an effective approach to modulate the catalytic performance of metals supported on oxides based on metal-support interaction. [ABSTRACT FROM AUTHOR]

Kinetics of the synthesis of C 2+ oxygenates directly from syngas was investigated over a series of Rh–MnO x /SiO 2 catalysts (atomic ratio of Mn/Rh=0, 0.5 and 5.0). It was evidenced that the activation energies for C 2+ oxygenates changed little when introducing MnO x , while the apparent activation energies for hydrocarbons, especially methane, increased remarkably. Kinetic parameters indicate that the formation of hydrocarbons can be suppressed in the presence of MnO x . In the meantime, the reaction orders with respect to different products were also altered with the variation of MnO x loadings. In accordance with in situ DRIFTS, we found that two new active sites on Rh surfaces resulting from the Rh–MnO x interaction might be responsible for the enhancement of reaction rates and the selectivity to C 2+ oxygenates. However, the over-loading of MnO x leads to a decrease in the number of active sites. [ABSTRACT FROM AUTHOR]

C 2+ oxygenates synthesis directly from syngas is one of the most promising processes for utilizing non-oil fossil fuels cleanly and efficiently. Bimetallic Rh–MnO x /SiO 2 catalysts with different Rh/Mn ratios were prepared and characterized with HRTEM, TPD and TPR. It was evidenced that Rh nanoparticles were stabilized in a range 0.5–2.0 nm via the promotional effects of MnO x . Meanwhile the interface between Rh and MnO x was assumed to be favorable for the insertion of CO into Rh–CH x to form C 2+ oxygenates; the intrinsic kinetics was performed over Rh (1.5 wt%)–Mn (0.4 wt%) catalysts at different temperatures. The kinetic parameters, including apparent activation energies and reaction orders, were calculated. With the combination of structural modification and kinetics, the reaction mechanism and the Mn promotional effects on Rh catalysts were elaborated. [ABSTRACT FROM AUTHOR]