Office for Technology Commercialization

Energy Transfer in Organic Photovoltaic Cells Using Interfacial Exciton Gates

Technology #20150023

Questions about this technology? Ask a Technology Manager

Download Printable PDF

Image Gallery
Exciton DensityExciton
Russell Holmes, PhD
Professor and Director of Graduate Studies, Materials Science and Engineering
External Link (
Managed By
Kevin Nickels
Technology Licensing Officer 612-625-7289
Patent Protection

US Patent Pending US20160104853
Directing Energy Transport in Organic Photovoltaic Cells Using Interfacial Exciton Gates
ACS Nano, 2015, 9 (4), pp 4543–4552
Tailored exciton diffusion in organic photovoltaic cells for enhanced power conversion efficiency
Nature Materials, 2013, 12, 152–157

Directed Exciton Transport

Directed exciton transport is achieved by incorporating exciton permeable interfaces that introduce a symmetry-breaking imbalance in exciton energy transfer. The new method for energy transport in organic photovoltaic cells exploits super-diffusive motion for enhanced exciton transport by creating an energy imbalance across exciton permeable interfaces. The technology intentionally biases energy transfer and exciton transport toward a donor-acceptor (D-A) interface while also increasing exciton diffusion efficiency for the device. This approach directs exciton motion to a desired location quickly (i.e., less than their natural lifetime). The applications for this OPV technology may also apply to a broader array of organic optoelectronic devices where excitons play a mediating role in the conversion of light to charge and vice versa.

Exciton Directional Control Improves Efficiency

Organic photovoltaics (OPV) have advantages over traditional solar cells in that they can be printed on flexible substrates, are low cost and lightweight, but they suffer from lower efficiency than solar cells. Inorganic excitons (Mott-Wannier variety) are susceptible to conventional control mechanisms like electric fields, while organic Frenkel-type excitons are so tightly bound their motion cannot have be biased by an electric field. As such, most organic devices do not impart directional control over exciton dynamics and rely on isotropic diffusion. The interfacial exciton gates introduced in this technology are a new means of achieving biased motion of excitons. This direct exciton transport technology improves efficiency by creating an energy imbalance at the interface between layers and helps excitons reach desired locations or ensure they avoid regions where they may experience unwanted decay mechanisms.


  • Creates an energy imbalance at the interface between layers
  • Directional control moves excitons to desired locations faster/more efficiently than diffusion
  • May improve stability
  • State of the art efficiency (for OPV)
  • Ensures excitons avoid unwanted decay mechanisms
  • Low cost processing, high throughput, and compatible with lightweight, flexible substrates


  • Photovoltaic applications
  • Solar cells
  • Excitonic optoelectronic devices (e.g., organic photovoltaics, organic light emitting devices, organic photodetectors, or next generation excitonic devices such as exciton logic circuits)
  • Commercial products that generate electricity, detect light, and emit light (e.g., lighting, displays (TV and phone), solar cells and detectors)
  • Integration with clothing and fabric surfaces

Phase of Development - Proof of Concept

Interested in Licensing?
The University relies on industry partners to scale up technologies to large enough production capacity for commercial purposes. The license is available for this technology and would be for the sale, manufacture or use of products claimed by the issued patents. Please contact Kevin Nickels to share your business needs and technical interest in this photovoltaic technology and if you are interested in licensing the technology for further research and development.