UDRI Awarded Contract for Polymer Research

The Polymers group, part of UDRI’s Nonmetallic Materials division, was recently awarded a five-year, multi-million dollar contract by the Air Force Research Laboratory’s Materials and Manufacturing Directorate. Dr. Chyi-Shan Wang, Polymers group leader, leads this program at Wright-Patterson AFB to develop novel polymeric materials that have superior thermal, mechanical, electrical, electronic and optical properties for advanced structural, photonic, electro-optical, and opto-electronic applications in space and aerospace systems.

The new contract continues a two-decade long working relationship between UDRI’s Polymers group and the Air Force Research Laboratory. To help meet Air Force needs, the group has conducted research in new polymer synthesis and formulation, sample design and prototype device fabrication, and structure and property characterizations.

Among other tasks, the group has conducted research on the synthesis, processing, and characterization of polymers with aromatic-heterocyclic rigid-rod and ladder structures. Using these polymers, the goal of the group is to develop a class of new and highly efficient polymer-based heterojunction photovoltaic cells.

A photovoltaic or solar cell converts the radiant energy of sunlight directly and efficiently into electrical energy. It does this by utilizing the “photovoltaic effect,” in which the absorption of light or other electromagnetic radiation causes the production of a current through the separation of electrons and “holes” at the interface of two semiconductor materials. One of these materials is a “p-type” semiconducting material, which “donates” electrons, and the other is an “n-type” semiconducting material, which accepts electrons.

UDRI’s interdisciplinary team includes chemists who synthesize novel and stable n-doped or n-type polymers with rigid-rod and ladder geometries, and engineers who design and fabricate photovoltaic cells using new electrode materials (such as carbon nanotubes) and new device architectures. The physicists in the group characterize the electronic behavior of the resulting photovoltaic devices in order to understand and optimize their mechanism and efficiency.

The general trend in photovoltaic technology development is towards ever-higher efficiency and lower cost devices.  The group’s current research has the potential to be quickly applied toward producing high-performance, low-cost, flexible, polymer-based photovoltaic cells.  These high-efficiency solar cells can be an important energy source for space and aerospace systems, in addition to being a potential source for terrestrial power.  The new photovoltaic cells could also be integrated into consumer goods such as toys, smart-cards, electronic equipment with low energy consumption, and solar homes and buildings, resulting in a substantial increase in the use of affordable solar energy in daily life.

March 2001