Nanocomposites of Cu2O with plasmonic metals (Au, Ag): design, synthesis, and photocatalytic applications.

Metal-semiconductor nanocomposites have been utilized in a multitude of applications in a wide array of fields, prompting substantial interest from different scientific sectors. Of particular interest are semiconductors paired with plasmonic metals due to the unique optical properties that arise from the individual interactions of these materials with light and the intercomponent movement of charge carriers in their heterostructure. This review focuses on the pairing of Cu2O semiconductor with strongly plasmonic metals, particularly Au and Ag. The design and synthesis of Au-Cu2O and Ag-Cu2O nanostructures, along with ternary nanostructures composed of the three components, are described, with in-depth discussion on the synthesis techniques and tunable parameters. The effects of compositing on the optical and electronic properties of the nanocomposites in the context of photocatalysis are discussed as well. Concluding remarks and potential areas for exploration are presented in the last section.

Gold-decorated TiO2 nanofibrous hybrid for improved solar-driven photocatalytic pollutant degradation.

TiO2-based nanomaterials are among the most promising photocatalysts for degrading organic dye pollutants. In this work, Au-TiO2 nanofibers were fabricated by the electrospinning technique, followed by calcination in air at 500 °C. Morphological and structural analyses revealed that the composite consists of TiO2 nanofibers with embedded Au nanoparticles that are extensively distributed throughout the porous fibrous structure of TiO2. The photocatalytic performance of these Au-embedded TiO2 nanofibers was evaluated in the photodegradation of Rhodamine B and methylene blue under solar simulator irradiation. Compared with pristine TiO2 nanofibers, the Au-embedded TiO2 nanofibers displayed far better photocatalytic degradation efficiency. The plasmon resonance absorption of Au nanoparticles in the visible spectral region and the effective charge separation at the heterojunction of the Au-TiO2 hybrid are the key factors that have led to the considerable enhancement of the photocatalytic activity. The results of this study clearly demonstrate the potential of Au-TiO2 electrospun nanofibers as solar-light-responsive photocatalysts for the effective removal of dye contaminants from aquatic environments.