Bio: My research focuses on applying inorganic chemistry to nanotechnology for chemical and environmental sensing. One project focuseson photoluminescent and electroluminescent silole and polysiloles nanowires as sensors for detecting explosives. There has been wide interest in this research, because of its relevance to homeland security problems. Another focus is developing functionalized polysiloles and silole nanoparticles (Figure 1) for detecting carcinogenic and toxic chromium(VI) and arsenic(V). Potential applications include remote sensing and industrial process control. The focus on chromium(VI) and arsenic(V) is dictated by the redoxquenching mechanism that is being used, as well as by the importance of chromium(VI) and arsenic(V) as regulated chemicals under the EPA Safe Drinking Water Act. Novel dehydrocoupling catalytic chemistry is also being explored as a convenient synthetic route to novel inorganic polymers. Photophysical characterization of polymer luminescence and quenching is also being explored in collaboration with Professor Magde's group.

There is tremendous interest in the development of inexpensive portable electronic devices for the specific detection of toxic chemicals, such as terrorist nerve agents, as well as for monitoring gaseous pollutants. In current collaborative research with professors Kummel (Chemistry), Schuller (Physics), and Lo (Electrical Engineering), as part of the Integrated Nanosensors Laboratory at UCSD, we are exploring physical vapor deposition of discrete transition metal complexes to construct resistive, capacitive, and chemical field effect transitors that function as chemical sensors. This research involves the synthesis of robust metal complexes that can be vapor deposited as nanoscale films across electrodes for resistive sensing, or into a MEMS cantilever or microcapicator for capacitive sensing. Such chemoresponsive electronic devices have potential wide application as manufacturable chemosensors.

Research: