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Peter Santiago

Peter Santiago

Major: 

Physics

University: 

California State University Long Beach

Mentor(s): 

David Cao

Faculty Sponsor(s): 

Thuc-Quyen Nguyen

Faculty Sponsor's Department(s): 

Chemistry and Biochemistry

Project Title: 

Characterization of Organic Semiconductors Doped by the Lewis Acid BCF

Project Description: 

There has been renewed interest in making flexible organic devices for widely ranging applications such as medical devices and flexible displays. Progress had been stalled due to issues with processability and aggregation of the heavily studied p-dopant F4TCNQ in polymer thin films. Lewis acids hold promise in advancing these devices beyond the limits of F4TCNQ - however the mechanism on their doping is not well understood. We propose that the addition of the Lewis acid tris(pentafluorophenyl)borane (BCF) to organic semiconducting polymers will introduce holes that in turn increase the mobility of the electrons. To elucidate BCF’s influence on three different polymers, we analyze several different ratios of BCF:polymer with Atomic Force Microscopy (AFM) and Ultraviolet-Visible Spectroscopy (UV-Vis) to obtain surface morphology and electrical properties respectively. An altered morphology can create obstacles or “potholes” for electrons as they travel, which in turn will lower the conductivity of the sample. Film absorption gives insight on the interaction between BCF and the polymer providing a more holistic understanding on it’s doping. We expect our surface morphology to be constant thus demonstrating no aggregation of BCF while the UV-Vis data is predicted to be similar to F4TCNQ due to an increase in hole concentration for improved conductivity. These results will help to add to the pieces of the larger puzzle, which is understanding the doping mechanism of semiconducting polymers by Lewis acids.