David T. Pierce

Developments and Applications of Electrogenerated Chemiluminescence Sensors Based on Micro- and Nanomaterials

A variety of recent developments and applications of electrogenerated chemiluminescence (ECL) for sensors are described. While tris(2,2′-bipyridyl)-ruthenium(II) and luminol have dominated and continue to pervade the field of ECL-based sensors, recent work has focused on use of these lumophores with micro- and nanomaterials. It has also extended to inherently luminescent nanomaterials, such as quantum dots. Sensor configurations including microelectrode arrays and microfluidics are reviewed and, with the recent trend toward increased use of nanomaterials, special attention has been given to sensors which include thin films, nanoparticles and nanotubes. Applications of ECL labels and examples of label-free sensing that incorporate nanomaterials are also discussed.

Silica nanoparticles for template synthesis of supported Pt and Pt-Ru electrocatalysts.

A simple method was developed for the template synthesis of silica-supported Pt and bimetallic Pt-Ru nanocatalysts. The synthesis used amine-functionalized silica nanoparticles as both template and support for the formation of metal nanoclusters with a precise composition, narrow size distribution, uniform shape and close spatial association. The nanocatalysts were compared with a commercial Pt-C catalyst used in fuel cell applications. Electrochemical measurements of methanol oxidation demonstrated higher catalytic activity for silica-supported Pt nanocatalysts and a reduced CO poisoning effect from co-templating of Pt and Ru.

Photoactive Nanomaterials for Sensing Trace Analytes in Biological Samples

The emerging field of nanotechnology has provided several revolutionary photoactive nanomaterials as labeling reagents for ultrasensitive and accurate determination of trace amounts of target analytes in biological samples. Currently, different types of photoactive nanomaterials have been developed, which include quantum dots, PEBBLEs, polymer fluorescent nanoparticles, silica fluorescent nanoparticles, metal nanoparticles, etc. All of these nanosensing substrates have demonstrated excellent signaling characteristics and high photostability for a wide variety of photoluminescent, photoabsorent, and photodispersive assays. This review focuses mainly on some recent applications of these nanomaterials for sensitive determination of trace analytes in biological samples.

Nanocatalysts in Direct Methanol Fuel Cell Applications

Current needs for sustainable energy have popularized the development and use of fuel cell technology. Fuel cells provide a clean alternative to other types of energy. Since this is a relatively new technology, many aspects of this field still need improvement. Catalysts are vital fuel cell components, and in recent years research efforts have focused on the development new types of catalysts. This review describes the deficiencies of several types of catalysts used in hydrogen and direct‐methanol fuel‐cell applications and the recent development of new catalysts for these devices based on nanoscale materials. Several important types of nanocatalysts (Pt‐Ru nanocomposites, gold nanocatalysts, and carbon nanotubes supported Pt‐Fe) will be covered. In addition, the merits and shortcomings of these nanocatalysts will be briefly discussed.

One-Pot Synthesis of Reduced Graphene Oxide/Metal (Oxide) Composites

Graphene, one of the most attractive two-dimensional nanomaterials, has demonstrated a broad range of applications because of its excellent electronic, mechanical, optical, and chemical properties. In this work, a general, environmentally friendly, one-pot method for the fabrication of reduced graphene oxide (RGO)/metal (oxide) (e.g., RGO/Au, RGO/Cu2O, and RGO/Ag) composties was developed using glucose as the reducing agent and the stabilizer. The glucose not only reduced GO effectively to RGO but also reduced the metal precursors to form metal (oxide) nanoparticles on the surface of RGO. Moreover, the RGO/metal (oxide) composites were stabilized by gluconic acid on the surface of RGO. The developed RGO/metal (oxide) composites were characterized using STEM, FE-SEM, EDS, UV-vis absorption spectroscopy, XRD, FT-IR, and Raman spectroscopy. Finally, the developed nanomaterials were successfully applied as an electrode catalyst to simultaneous electrochemical analysis of l-ascorbic acid, dopamine, and uric acid.