Polymer solar cells employing Forster resonance energy transfer

Aug 20, 2013
Polymer Solar Cells Employing Förster Resonance Energy Transfer
Next generation solar panels could yield substantially lower costs per kilowatt-hour with this technological development.

Two crucial tasks exist for realizing high-efficiency polymer solar cells: increasing the range of the spectral absorption of light and efficiently harvesting photo-generated excitons. In this work, Förster resonance energy transfer (FRET)-based heterojunction polymer solar cells that incorporate squaraine dye (SQ) were fabricated and investigated.

The high absorbance of squaraine in the near-infrared region broadens the spectral absorption of the solar cells and assists in developing an ordered nano-morphology for enhanced charge transport. Femtosecond spectroscopic studies revealed highly efficient (up to 96%) excitation energy transfer from poly(3-hexylthiophene), also known as P3HT, to squaraine occurring on a picosecond timescale.

A 38% increase in was realized to reach 4.5%; this finding suggests that this system has improved exciton migration over long distances. This architecture transcends traditional multiblend systems, allowing multiple donor materials with separate spectral responses to work synergistically, thereby enabling an improvement in and conversion. This discovery opens up a new avenue for the development of high-efficiency polymer solar cells.

A new energy transfer mechanism has been exploited for the first time, allowing significantly more efficient energy harvesting in P3HT/dye solar cells compared to P3HT-alone solar cells. Also, broadening the light into the near-infrared region and developing nanoscale parts to the solar cell has improved the device.

Allowing different light-absorbing materials to work synergistically has led to well-ordered polymer networks without post-processing.

Energy level diagram of the components of the ternary blend solar cell highlighting pathways for charge generation.

What are the specifics?

  • CFN Capability: CFN's Advanced Optical Spectroscopy & Microscopy Facility was used to understand the energy conversion mechanism and rate of electronic transfer between the dye and polymer in the solar cells.
  • The use of squaraine dye and FRET of charge carriers improved the efficiency of polymer solar cells.  Femtosecond spectroscopic studies revealed highly efficient excitation energy transfer from P3HT to SQ occurring on a picosecond timescale.  This suggested that this system has improved exciton migration over .
  • For the first time, FRET was exploited to enhance exciton harvesting in polymer bulk heterojunction solar cells.

Explore further: 3-D images of tiny objects down to 25 nanometres

More information: Huang, J. et al. Polymer bulk heterojunction solar cells employing Förster resonance energy transfer, Nature Photonics 7, 479-485 (2013).

Related Stories

The fluorescent future of solar cells

May 09, 2013

(Phys.org) —For some solar cells, the future may be fluorescent. Scientists at Yale have improved the ability of a promising type of solar cell to absorb light and convert it into electrical power by adding ...

Plastic solar cells' new design promises bright future

Aug 14, 2013

Energy consumption is growing rapidly in the 21st century, with rising energy costs and sustainability issues greatly impacting the quality of human life. Harvesting energy directly from sunlight to generate electricity using ...

UCLA scientists double efficiency of novel solar cell

Jul 29, 2013

Nearly doubling the efficiency of a breakthrough photovoltaic cell they created last year, UCLA researchers have developed a two-layer, see-through solar film that could be placed on windows, sunroofs, smartphone ...

Team makes breakthrough in solar energy research

Jul 30, 2013

The use of plasmonic black metals could someday provide a pathway to more efficient photovoltaics (PV) —- the use of solar panels containing photovoltaic solar cells —- to improve solar energy harvesting, ...

Recommended for you

3-D images of tiny objects down to 25 nanometres

Mar 30, 2015

Scientists at the Paul Scherrer Institute and ETH Zurich (Switzerland) have created 3D images of tiny objects showing details down to 25 nanometres. In addition to the shape, the scientists determined how ...

Solving molybdenum disulfide's 'thin' problem

Mar 27, 2015

The promising new material molybdenum disulfide (MoS2) has an inherent issue that's steeped in irony. The material's greatest asset—its monolayer thickness—is also its biggest challenge.

Snowflakes become square with a little help from graphene

Mar 25, 2015

The breakthrough findings, reported in the journal Nature, allow better understanding of the counterintuitive behaviour of water at the molecular scale and are important for development of more efficient techno ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.