Dr. Timothy Smith's research interests fall under the umbrella of applying semiconducting polymers (SCP) to sensor applications and renewable energy research. SCP such as those derived from the technologically and theoretically important polymer poly(p-phenylenevinylene) (PPV) are rapidly setting the stage for a new era of microelectronics—an era in which plastic materials will take on many of the functions and properties of inorganic semiconductors. Developing light weight, low power consumption semiconducting sensors that are field-portable could be a necessary step toward arresting toxic exposure to PCB’s by detecting and quantifying this class of materials in the environment.

Perhaps one of the single greatest challenges to overcome in developing SCP for sensor applications is the effect of aggregation on polymer morphology. Properties such as photo-emission and charge migration are essential to applications such as electroluminescence and photocurrent generation and are sensitive morphological defects. Using basic solution chemistry is possible to coax soluble oligomers of semiconducting conjugated polymers into aggregates. The degree of aggregation and morphology of these aggregates could easily be studied using fluorescence microscopy, atomic force microscopy, circular dichroism, and Stark spectroscopy.

Photovoltaic applications based on SCP may well pave the way to the development of light-weight, portable, high conversion efficiency solar power technology. Photoconductive properties of conjugated polymers such as polythiophenes (PS) have already demonstrated a significant advantage over contemporary inorganic photovoltaic device and are capable of generating open circuit voltages (voltage produced in the absence of current) approaching 2 V—approximately twice that of the inorganic device. Implications of this finding translate to 50% less polymer-based photovoltaic cells would be needed to generate a comparable amount of power to that obtained from inorganic photovoltaic systems. One current limitation to implementing SCP into photovoltaic device is the apparent loss in quantum efficiency that occurs during the production of polymer thin films. It is the orientation of polymers in these films that directly influences photoconductivity.