Our research touches several aspects of organic solar cells (OPVs): synthesis of new materials, nanoscale characterization, and device fabrication, engineering and optimization. With a dedicated team working on theory, simulation, and experiments, our ultimate goal is to understand how to achieve high efficiency photovoltaic devices.

We design and synthesize novel conjugated polymers, conjugated polyelectrolytes and related small molecules, and then incorporate into emerging electric and optoelectronic technologies such as light-emitting diodes, thin film transistors, electrochemical cells and photovoltaic devices.

Doping plays a crucial role in the development of semiconducting devices in electronics and optoelectronics. Doping phenomena in conjugated polymers are much more complicated compared to that in inorganic polymers, therefore, they are not well controlled. To gain insight on doping processes, we focus on the fundamental understanding of lewis acid doping and electrochemical doping. 

The performance of organic electronic devices is profoundly influenced by the nanoscale morphology of the organic film. For example, the active layer of a bulk heterojunction organic photovoltaic (BHJ OPV) device is a ~100 nm thick film consisting of a blend of an electron donating and electron accepting material that phase segregates to form nanoscale, bicontinuous domains.

Charge carrier transport and carrier recombination govern the operation of all electronic devices, including those utilizing organic semiconductors. Thus, understanding charge transport and charge recombination in organic semiconductors is a prerequisite for successfully designing future high performance organic electronic devices.

The operation of organic electronic devices strongly depends on the charge injection or charge extraction properties of the metal contact. The interfaces between metal electrodes and organic semiconducting materials play a crucial role in these processes.

We develop several high-performance solution-processed organic photodetectors and organic photomultipliers with wavelength detection in UV-Visible-Infrared ranges.

In order to understand and improve organic semiconductor-based devices, we deal with devices as a whole, investigating charge injection, interfacial phenomena, and current-voltage properties. The examples of organic devices that we have been working on are: Organic Ratchets, Organic diodes, Organic Field Effect Transistors and Organic Electrochemical Transistors

Bioelectronics has become omnipresent in several key technologies, especially in biomedical engineering. We develop bioelectronics based on water soluble conjugated polyelectrolytes and based on bio-compatible materials and devices. For example, we develop transmembrane electron transfer via embedded oligomers for microbial fuel power generation, bio-sensing organic transistors, physiology monitoring organic photo-detectors.

Electrochemistry is experiencing a "renaissance" in recent years in the fields of organic electrosynthesis, battery engineering, and "single-entity electrochemistry." Using state-of-the-art potentiostatic and galvanostatic modes, it is possible to learn about the thermodynamics of the reaction and the kinetics of charge transfer. We are exploring charge transfer phenomena both at the macroscopic level and at the individual molecule level.

Using protein engineering and directed evolution, we are leveraging enzymatic platforms to impose precise regio- and stereo-control over challenging catalytic reactions. Using an interdisciplinary approach combining organic chemistry, organometallic chemistry, enzymology, and protein engineering, we expand the catalytic repertoire of enzymatic machineries well beyond nature’s biochemical landscape.

The focus of this research is to break down barriers between endogenous biochemical signals and exogenous soft materials for the fabrication of smart devices. A major aim is to revisit biomedical problems that remain shockingly unsolved, by integrating structurally dynamic chemistries and biomaterials into autonomous sense-response-feedback platforms.