The performance of CuO/CeO2 catalysts for CO oxidation strongly depends on the type of copper precursor and the calcination temperature.

Nonequilibrium phase transitions play a pivotal role in broad physical contexts, from condensed matter to cosmology. Tracking the formation of nonequilibrium phases in condensed matter requires a resolution of the long-range cooperativity on ultra-short timescales. Here, we study the spontaneous transformation of a charge-density wave in CeTe3 from a stripe order into a bi-directional state inaccessible thermodynamically but is induced by intense laser pulses. With ≈100 fs resolution coherent electron diffraction, we capture the entire course of this transformation and show self-organization that defines a nonthermal critical point, unveiling the nonequilibrium energy landscape. We discuss the generation of instabilities by a swift interaction quench that changes the system symmetry preference, and the phase ordering dynamics orchestrated over a nonadiabatic timescale to allow new order parameter fluctuations to gain long-range correlations. Remarkably, the subsequent thermalization locks the remnants of the transient order into longer-lived topological defects for more than 2 ns.

We demonstrate the surface plasmon (SP) enhanced n-ZnO/AlN/p-GaN light-emitting diodes (LEDs) by inserting the Ag nanoparticles (NPs) between the ZnO and AlN layers. The ultraviolet/violet near band edge emission of the device is significantly enhanced while the green defect-related emission is modestly suppressed compared to the LEDs without Ag NPs. The red-shift of electroluminescence (EL) peak and the reduced photoluminescence decay lifetime of ZnO suggest that the improved EL performance of the device with Ag NPs is attributed to the resonant coupling between excitons in ZnO and localized SPs in Ag NPs.

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