BACKGROUND The safe use in biomedicine of semiconductor nanoparticles, also known as quantum dots (QDs), requires a detailed understanding of the biocompatibility and toxicity of QDs in human beings. The biological characteristics and physicochemical properties of QDs entail new challenges regarding the management of potential adverse health effects following exposure. At certain concentrations...

Semiconductor Nanomaterials in Photocatalytic Bipyridine Reduction and H2 Generation By Li Yu Semiconductor nanoparticles have been used in the study of proton coupled electron transfer from CdS quantum dots (QDs) to N-heptyl-4,4’-bipyridinium (bPYD) and photocatalytic H2 generation with Pt tipped CdS nanorods (NRs) under alkaline solutions. For the QDs/bPYD system, transient absorption (TA) sp...

Photocatalytic activity of semiconductor nanostructures is gaining much importance in recent years in both energy and environmental applications. However, several parameters play a crucial role in enhancing or suppressing the photocatalytic activity through, for example, modifying the band gap energy positions, influencing the generation and transport of charge carriers and altering the recombi...

The self-assembly of CdS semiconductor nanocrystals (Q-CdS) as well-defined monolayer and multilayer films on glass, indium tin oxide, and gold surfaces was carried out. These were characterized by ultraviolet-visible spectroscopy, ellipsometry, and scanning tunneling microscopy. The adsorption of the polymeric anion hexametaphosphate (HMP) on the Q-CdS particle surface produced a negative surf...

Molecules of a thiol-functionalized phenylacetylene derivative were assembled on the CdS nanorod surface and copolymerized with phenylacetylene, affording an inorganic semiconductor-conjugated polymer hybrid with excellent solubility and high photoconductivity.

Considerable effort has been made to fabricate graphene (GR)/semiconductor composite photocatalysts, by using graphene oxide (GO) as the most widely used precursor of GR, toward an improved efficacy of solar energy conversion. However, thus far, the role of GO in the preparation and photocatalytic activity of GR/semiconductor composites has remained rather elusive. Herein, we report a simple ye...

Amphiphilic block copolymer poly(isoprene-b-acrylic acid) (PI-b-PAA) was used to stabilize exfoliated graphene in water, allowing the immobilization of semiconductor CdS nanoparticles forming CdS • PI-b-PAA/graphene. Characterization using high-resolution transmission electron microscopy and energy-dispersive x-ray spectroscopy proved the success of the preparation method and revealed the prese...

The nature of exciton-plasmon interactions in Au-tipped CdS nanorods has been investigated using femtosecond transient absorption spectroscopy. The study demonstrates that the key optoelectronic properties of composite heterostructures comprising electrically coupled metal and semiconductor domains are substantially different from those observed in systems with weak interdomain coupling. In par...

Non-resonant Raman spectroscopy studies of a set of CdS films annealed at different temperatures were performed and showed a direct correlation between the width of the Raman peak produced by CdS-like optical phonons and the crystalline quality of the semiconductor phase probed by x-ray diffraction (XRD) and transmission electron microscopy (TEM). In order to decribe the Raman lineshape a model...

We report on the first synthesis of a heterostructured semiconductor tetrapod from CdSe@CdS that carries a single dipolar nanoparticle tip from a core-shell colloid of Au@Co. A four-step colloidal total synthesis was developed, where the key step in the synthesis was the selective deposition of a single AuNP tip onto a CdSe@CdS tetrapod under UV-irradiation. Synthetic accessibility to this dipo...