Wavelength-Dependent Bifunctional Plasmonic Photocatalysis in Au/Chalcopyrite Hybrid Nanostructures.

Excited, or "hot" charge carrier generation and transfer driven by the decay of localized surface plasmon resonances (LSPRs) are key steps in plasmonic photocatalysis. Hybrid structures that contain both metal and semiconductor building blocks facilitate the extraction of reactive charge carriers and their utilization for photoelectrocatalysis. Additional functionality arises from hybrid structures that combine noble metal nanostructures with semiconductor components, such as chalcopyrite (CuFeS) nanocrystals (NCs), which by themselves support quasistatic resonances.

An organometallic catalase mimic with exceptional activity, HO stability, and catalase/peroxidase selectivity.

Manganese-porphyrin and -salen redox therapeutics catalyze redox reactions involving O˙, HO, and other reactive oxygen species, thereby modulating cellular redox states. Many of these complexes perform catalase reactions high-valent Mn-oxo or -hydroxo intermediates that oxidize HO to O, but these intermediates can also oxidize other molecules (, thiols), which is peroxidase reactivity. Whether catalase or peroxidase reactivity predominates depends on the metal-ligand set and the local environment, complicating predictions of what therapeutic effects (, promoting suppressing apoptosis) a complex might produce in a given disease.

Microstructural control of modular peptide release from microporous biphasic calcium phosphate.

Drug release from tissue scaffolds is commonly controlled by using coatings and carriers, as well as by varying the binding affinity of molecules being released. This paper considers modulating synthetic peptide incorporation and release through the use of interconnected microporosity in biphasic calcium phosphate (BCP) and identifies the microstructural characteristics important to the release using experiments and a model of relative diffusivity. First, the release of three modular peptides designed to include an osteocalcin-inspired binding sequence based on bone morphogenic protein-2 (BMP-2) was compared and one was selected for further study.

Sense and shoot: simultaneous detection and degradation of low-level contaminants using graphene-based smart material assembly.

Smart material nanoassemblies that can simultaneously sense and shoot low-level contaminants from air and water are important for overcoming the threat of hazardous chemicals. Graphene oxide (GO) sheets deposited on mesoscopic TiO2 films that underpin the deposition of Ag nanoparticles with UV irradiation provide the foundation for the design of a smart material. The Ag particle size is readily controlled through precursor concentration and UV irradiation time.

Graphitic design: prospects of graphene-based nanocomposites for solar energy conversion, storage, and sensing.

Graphene not only possesses interesting electrochemical behavior but also has a remarkable surface area and mechanical strength and is naturally abundant, all advantageous properties for the design of tailored composite materials. Graphene-semiconductor or -metal nanoparticle composites have the potential to function as efficient, multifunctional materials for energy conversion and storage. These next-generation composite systems could possess the capability to integrate conversion and storage of solar energy, detection, and selective destruction of trace environmental contaminants or achieve single-substrate, multistep heterogeneous catalysis.

Electron Hopping Through Single-to-Few-Layer Graphene Oxide Films. Side-Selective Photocatalytic Deposition of Metal Nanoparticles.

Single- to few-layer graphene oxide (GO) sheets have been successfully anchored onto TiO2 films using electrophoretic deposition. Upon UV illumination of TiO2-GO films, photogenerated electrons from TiO2 are captured by GO. These electrons are initially used in GO's reduction, while additional electron transfer results in storage across its sp(2) network.

Fortification of CdSe quantum dots with graphene oxide. Excited state interactions and light energy conversion.

Graphene based 2-D carbon nanostructures provide new opportunities to fortify semiconductor based light harvesting assemblies. Electron and energy transfer rates from photoexcited CdSe colloidal quantum dots (QDs) to graphene oxide (GO) and reduced graphene oxide (RGO) were isolated by analysis of excited state deactivation lifetimes as a function of degree of oxidation and charging in (R)GO. Apparent rate constants for energy and electron transfer determined for CdSe-GO composites were 5.

Sun-believable solar paint. A transformative one-step approach for designing nanocrystalline solar cells.

A transformative approach is required to meet the demand of economically viable solar cell technology. By making use of recent advances in semiconductor nanocrystal research, we have now developed a one-coat solar paint for designing quantum dot solar cells. A binder-free paste consisting of CdS, CdSe, and TiO(2) semiconductor nanoparticles was prepared and applied to conducting glass surface and annealed at 473 K.

Electron transfer cascade by organic/inorganic ternary composites of porphyrin, zinc oxide nanoparticles, and reduced graphene oxide on a tin oxide electrode that exhibits efficient photocurrent generation.

A bottom-up strategy has been developed to construct a multiple electron transfer system composed of organic/inorganic ternary composites (porphyrin, zinc oxide nanoparticles, reduced graphene oxide) on a semiconducting electrode without impairing the respective donor-acceptor components. The hierarchical electron transfer cascade system exhibited remarkably high photocurrent generation with an incident-photon-to-current efficiency of up to ca. 70%.

Anchoring semiconductor and metal nanoparticles on a two-dimensional catalyst mat. Storing and shuttling electrons with reduced graphene oxide.

Using reduced graphene oxide (RGO) as a two-dimensional support, we have succeeded in selective anchoring of semiconductor and metal nanoparticles at separate sites. Photogenerated electrons from UV-irradiated TiO(2) are transported across RGO to reduce silver ions into silver nanoparticles at a location distinct from the TiO(2) anchored site. The ability of RGO to store and shuttle electrons, as visualized via a stepwise electron transfer process, demonstrates its capability to serve as a catalyst nanomat and transfer electrons on demand to adsorbed species.