We report an investigation on the effect of stabilization agents and surface curvatures on oxidative etching of three classes of anisotropically shaped gold nanoparticles namely, rods, bipyramids and prisms. In particular, the dual role of the 10 stabilizing agent CTAB in the etching process is explored, showing how it acts both as a source of bromine ions, accelerating etching and as a protection agent, resulting in anisotropic reshaping.

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The performance of zeolites as solid acid catalysts is strongly influenced by the accessibility of active sites. However, synthetic zeolites typically grow as complex aggregates of small nanocrystallites rather than perfect single crystals. The structural complexity must therefore play a decisive role in zeolite catalyst applicability. Traditional tools for the characterization of heterogeneous catalysts are unable to directly relate nanometer-scale structural properties to the corresponding catalytic performance. In this work, an innovative correlative super-resolution fluorescence and scanning electron microscope is applied, and the appropriate analysis procedures are developed to investigate the effect of small-port H-mordenite (H-MOR) morphology on the catalytic performance, along with the effects of extensive acid leaching. These correlative measurements revealed catalytic activity at the interface between intergrown H-MOR crystallites that was assumed inaccessible, without compromising the shape selective properties. Furthermore, it was found that extensive acid leaching led to an etching of the originally accessible microporous structure, rather than the formation of an extended mesoporous structure. The associated transition of small-port to large-port H-MOR therefore did not render the full catalyst particle functional for catalysis. The applied characterization technique allows a straightforward investigation of the zeolite structure–activity relationship beyond the single-particle level. We conclude that such information will ultimately lead to an accurate understanding of the relationship between the bulk scale catalyst behavior and the nanoscale structural features, enabling a rationalization of catalyst design.

Volumes of activation as determined from the effect of pressure on the exchange current were measured for nickel electrodeposition in the presence of several anionic additives. From the results it was concluded that in reaching the activated complex, two water molecules were lost in dilute chloride solutions, one was lost in boric acid and more concentrated chloride solutions, and none were lost in thiocyanate solutions. The results were interpreted in terms of an outer‐sphere electron‐transfer bridge in the case of the thiocyanate, and inner‐sphere bridges in the case of the chloride and the boric acid.