Catalytic CO oxidation on Pt under near ambient pressure: A NAP-LEEM study.

A near ambient pressure low-energy electron microscope (NAP-LEEM) has recently been constructed, that allows in situ imaging of surfaces up to a pressure of 10 mbar. Here we report on pattern formation in catalytic CO oxidation on a Pt(110) single crystal surface and on a polycrystalline Pt foil in the 10 mbar range, operating the microscope in the mirror electron microscopy (MEM) and in the LEEM mode. Excitations localized at structural defects and spiral wave fragments have been observed.

MOVPE growth of GaP/GaPN core-shell nanowires: N incorporation, morphology and crystal structure.

Dilute nitride III-V nanowires (NWs) possess great potential as building blocks in future optoelectronical and electrochemical devices. Here, we provide evidence for the growth of GaP/GaPN core-shell NWs via metalorganic vapor phase epitaxy, both on GaP(111)B and on GaP/Si(111) hetero-substrates. The NW morphology meets the common needs for use in applications, i.

Insights into Interfacial Changes and Photoelectrochemical Stability of In(x)Ga(1-x)N (0001) Photoanode Surfaces in Liquid Environments.

The long-term stability of InGaN photoanodes in liquid environments is an essential requirement for their use in photoelectrochemistry. In this paper, we investigate the relationships between the compositional changes at the surface of n-type In(x)Ga(1-x)N (x ∼ 0.10) and its photoelectrochemical stability in phosphate buffer solutions with pH 7.

Traveling interface modulations and anisotropic front propagation in ammonia oxidation over Rh(110).

The bistable NH3 + O2 reaction over a Rh(110) surface was explored in the pressure range 10(-6)-10(-3) mbar and in the temperature range 300-900 K using photoemission electron microscopy and low energy electron microscopy as spatially resolving methods. We observed a history dependent anisotropy in front propagation, traveling interface modulations, transitions with secondary reaction fronts, and stationary island structures.

A highly selective and self-powered gas sensor via organic surface functionalization of p-Si/n-ZnO diodes.

Selectivity and low power consumption are major challenges in the development of sophisticated gas sensor devices. A sensor system is presented that unifies selective sensor-gas interactions and energy-harvesting properties, using defined organic-inorganic hybrid materials. Simulations of chemical-binding interactions and the consequent electronic surface modulation give more insight into the complex sensing mechanism of selective gas detection.

Band engineered epitaxial 3D GaN-InGaN core-shell rod arrays as an advanced photoanode for visible-light-driven water splitting.

3D single-crystalline, well-aligned GaN-InGaN rod arrays are fabricated by selective area growth (SAG) metal-organic vapor phase epitaxy (MOVPE) for visible-light water splitting. Epitaxial InGaN layer grows successfully on 3D GaN rods to minimize defects within the GaN-InGaN heterojunctions. The indium concentration (In ∼ 0.

Lithium transport through nanosized amorphous silicon layers.

Lithium migration in nanostructured electrode materials is important for an understanding and improvement of high energy density lithium batteries. An approach to measure lithium transport through nanometer thin layers of relevant electrochemical materials is presented using amorphous silicon as a model system. A multilayer consisting of a repetition of five [(6)LiNbO3(15 nm)/Si (10 nm)/(nat)LiNbO3 (15 nm)/Si (10 nm)] units is used for analysis, where LiNbO3 is a Li tracer reservoir.