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Dynamic observation: The rapid oxidative redispersion of large Pt nanoparticles supported on ceria‐based oxide in autoexhaust catalysts is demonstrated in the absence of Cl by in situ XANES analysis. An atomic migration model accounts for the observed redispersion through the trapping of Pt species at sites on the Ce support that exhibit strong interactions between the Pt oxide and the support.

A positive muon spin rotation and relaxation (µ + SR) experiment on [Ca2CoO3]0.62[CoO2], (i.e., Ca3Co4O9, a layered thermoelectric cobaltite) indicates the existence of two magnetic transitions at ∼ 100 K and 400 -600 K; the former is a transition from a paramagnetic state to an incommensurate (IC) spin density wave (SDW) state. The anisotropic behavior of zero-field µ + SR spectra at 5 K suggests that the IC-SDW propagates in the a-b plane, with oscillating moments directed along the c-axis; also the IC-SDW is found to exist not in the [Ca2CoO3] subsystem but in the [CoO2] subsystem. In addition, it is found that the long-range IC-SDW order completes below ∼ 30 K, whereas the short-range order appears below 100 K. The latter transition is interpreted as a gradual change in the spin state of Co ions above 400 K. These two magnetic transitions detected by µ + SR are found to correlate closely with the transport properties of [Ca2CoO3]0.62 [CoO2].

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Dedicated to the Catalysis Society of Japan on the occasion of its 50th Anniversary Supported precious metals, such as platinum (Pt), rhodium (Rh), and palladium (Pd), are used to facilitate many industrial catalytic processes. Pt in particular is found at the core of catalysts used throughout the petrochemical industry: from bifunctional catalysts (isomerization/dehydrogenation) used for refining of hydrocarbon fuel stocks, to three-way (CO and hydrocarbon oxidation/NO x reduction) conversions within car exhausts. In this latter, ubiquitous applicationcommercialized in the USA and Japan in 1977 [1] -Pt has always been a pivotal component in the abatement of harmful gas emissions from gasoline-or diesel-driven engines. The ever-increasing appreciation of the damage that noxious gas emissions are doing to our environment and the finite availability of noble metals provide strong drivers for the continued study and optimization of the behavior of Pt-based three-way catalysts (TWCs). Central to technological progress in this area is a fundamental understanding of how these materials behave, which may allow us to stop them degrading or deactivating during operation.