Добірка наукової літератури з теми "Catalytic and optical properties"

AbstractNanoporous metals (NPMs) made by dealloying represent a class of functional materials with the unique structural properties of mechanical rigidity, electrical conductivity, and high corrosion resistance. They also possess a porous network structure with feature dimensions tunable within a wide range from a few nanometers to several microns. Coupled with a rich surface chemistry for further functionalization, NPMs have great potential for applications in heterogeneous catalysis, electrocatalysis, fuel cell technologies, biomolecular sensing, surface-enhanced Raman scattering (SERS), and plasmonics. This article summarizes recent advances in some of these areas and, in particular, we focus on the discussion of microstructure, catalytic, and optical properties of nanoporous gold (NPG). With advanced electron microscopy, three-dimensional tomographic reconstructions of NPG have been realized that yield quantitative characterizations of key morphological parameters involved in the intricate structure. Catalytic and electrocatalytic investigations demonstrate that bare NPG is already catalytically active for many important reactions such as CO and glucose oxidation. Surface functionalization with other metals, such as Pt, produces very efficient electrocatalysts, which have been used as promising fuel cell electrode materials with very low precious metal loading. Additionally, NPG and related materials possess outstanding optical properties in plasmonics and SERS. They hold promise to act as highly active, stable, and economically affordable substrates in high-performance instrumentation applications for chemical inspection and biomolecular diagnostics. Finally, we conclude with some perspectives that appear to warrant future investigation.

To enhance the optical and catalytic properties of TiO2, carbon nanodots (CNDs) are incorporated to prepare hybrid CNDs/TiO2 materials with different precursor concentrations and the photocatalytic characteristics are evaluated systematically. When the CNDs/TiO2 materials are excited optically, some high-energy photons are reabsorbed by those in the lower energy states, indicating that photon reabsorption of CNDs plays a key role. The results enrich our understanding of the optical and catalytic mechanisms and provide insight into the design of CNDs-based composites.

The g-C3N4 which is well known as a polymeric non-metal semiconductor, has been fabricated by thermal polymerization. It has also been used in catalytic applications including, photo-catalysis, removal and degradation of pollutants in water, Friedel-Crafts reactions, oxygen reduction reaction and etc. It has drawn noticeable research attention due to its economical and affordable fabrication, non-toxicity, biocompatibility, good thermal and electrical conductivity, high hardness, Corrosion resistance, and fireproofing properties. Therefore, the g-C3N4 has found non-catalytic applications including composites, cutting tools, improving surface properties, light emitting devices, optical sensors, and solar cells. In the current review, the novel and non-catalytic applications of g-C3N4 have been highlighted.