An optimized procedure was designed for the preparation of the microporous metal–organic framework (MOF) [Cu3(btc)2] (BTC=benzene‐1,3,5‐tricarboxylate). The crystalline material was characterized by X‐ray diffraction, optical microscopy, SEM, X‐ray photoelectron spectroscopy, N2 sorption, thermogravimetry, and IR spectroscopy of adsorbed CO. CO adsorbs on a small number of Cu2O impurities, and particularly on the free CuII coordination sites in the framework. [Cu3(btc)2] is a highly selective Lewis acid catalyst for the isomerization of terpene derivatives, such as the rearrangement of α‐pinene oxide to campholenic aldehyde and the cyclization of citronellal to isopulegol. By using the ethylene ketal of 2‐bromopropiophenone as a test substrate, it was demonstrated that the active sites in [Cu3(btc)2] are hard Lewis acids. Catalyst stability, re‐usability, and heterogeneity are critically assessed.

Spectroscopic studies of the mechanistic steps that occur on supported precious metal catalysts used in industrial and automotive applications are hampered by a dearth of suitable experimental methods. We used femtosecond laser excitation followed by nanosecond time-resolved in situ Fourier-transform infrared spectroscopy to initiate a catalytic reaction on alumina-supported silver catalysts, which are of interest in minimizing nitrogen oxide emissions from fuel-efficient lean-burn engines. We found that the key intermediate step in the reaction between carbon monoxide and nitric oxide is the flip of a cyanide group from a silver nanoparticle to the alumina support (with a lifetime of 2 microseconds), which indicates the central role played by the interface between the metal particle and the oxide support.

Jump to it! 2D IR pressure‐jump spectroscopy of adsorbed CO can be used to assess the accessibility and location of platinum nanoparticles supported on a zeolite and investigate the behavior of Pt atoms after thermal treatment (activation, catalytic reaction, sintering). Different Pt nanoparticle sintering mechanisms were observed in the mesopores and on the external surface of the ZSM‐5 support (see picture; HF=high and LF=low frequency).

Zwei Welten: 2D‐IR‐Drucksprung‐Spektroskopie von adsorbiertem CO lieferte Informationen über die Umgebung und Lage von Platin‐Nanopartikeln auf Zeolith‐Trägern und das Verhalten der Pt‐Atome nach thermischer Behandlung (Aktivierung, katalytische Reaktion, Sinterung). In den Mesoporen und auf der äußeren Oberfläche des Trägers werden unterschiedliche Arten von Sintermechanismen beobachtet (siehe Bild; HF/LF=Hoch‐ bzw. Tieffrequenz).

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An improved micro-reactor cell for IR spectroscopic studies of heterogeneous catalysis was built around a 5.8 GHz microwave cavity. The reactor can operate at 20 bars and with conventional heating up to 720 K, with reactant gas flows velocities (GHSV) from 25 000 to 50 000 h À1 . The temperature of the sample under microwave irradiation was measured by time resolved IR emission spectroscopy. The first experiment performed was the IR monitoring of the desorption of carbonates induced by irradiating an alumina sample by microwaves at 5.8 GHz.