EPSRC logo

Details of Grant 

EPSRC Reference: EP/F062095/1
Title: Biomimetic hybrid semiconductor photovoltaic devices
Principal Investigator: Wilson, Professor L
Other Investigators:
Richardson, Dr TH Lidzey, Professor D
Researcher Co-Investigators:
Project Partners:
Department: Physics and Astronomy
Organisation: University of Sheffield
Scheme: Standard Research
Starts: 01 April 2008 Ends: 30 September 2009 Value (£): 157,679
EPSRC Research Topic Classifications:
Materials Characterisation Materials Synthesis & Growth
Optoelect. Devices & Circuits Solar Technology
EPSRC Industrial Sector Classifications:
Electronics Energy
Related Grants:
Panel History:
Panel DatePanel NameOutcome
18 Jan 2008 Feasibility Studies for Energy Research II Announced
Summary on Grant Application Form
There is sufficient solar radiation striking the surface of the earth to provide all of our energy needs. The most direct way to convert this solar energy to electricity is to use a photovoltaic solar cell. Whilst there has been considerbale success in developing these devices, one major problem with present-day photovoltaic cells is that when a photon of light is absorbed about 50 per cent of the energy is lost as heat. The use of nanometre-scale semiconductors (quantum dots) offers a solution to this problem. It has been shown that absorption of short wavelength light quantum dots results in the creation of up to 7 electron-hole pairs from each photon. This is because the high energy carriers lose energy more effectively by creating extra carriers than by producing heat as in conventional, bulk semiconductors. So far it has not been possible to exploit this effect, although the prospect of quantum dot-based solar cells with 60 per cent efficiencies continues to drive significant efforts in this direction. The most common approach for quantum dot solar cells is to disperse the dots in a polymer to create a hybrid device and rely on charge transfer and separation for photovoltaic operation. However, these devices have very modest efficiencies of just a few per cent and are limited by poor carrier transport properties in the same way that all-polymer solar cells are. In our proposed work we will investigate a radically new strategy to bypass these problems, which has the potential to create a completely new class of hybrid semiconductor photovoltaic device based on energy transfer, rather than the usual charge transfer in present-day hybrids. Inspired by photosynthetic systems, our biomimetic approach incorporates a highly efficient quantum dot-based light harvesting region from which energy is transferred non-radiatively to a semiconductor device where charge separation (photocurrent generation) occurs. Whilst challenging, the development of our proposed hybrid devices would represent a major step forward in solar cell research, allowing for the first time the full benefits of quantum dots to be exploited. The hybrid solid-state architecture is robust, and takes advantage of the unique properties of semiconductor nanocrystals quantum dots for harvesting sunlight (e.g. multiple carrier generation from a single photon), highly efficient non-radiative energy transfer between the hybrid constituents and the excellent electronic properties of inorganic semiconductors. The near unity efficiency of the proposed energy transfer process provides a new way to realise the predicted 40 per cent improvement in quantum efficiency for quantum dot-based solar cells relative to bulk semiconductor devices. By demonstrating the feasibility of our energy transfer scheme we therefore have the potential to approach the predicted power conversion efficiencies for quantum dots of 42% (unconcentrated) and 58% (using a concentrator), vastly improving the values of 31% and 38% predicted for conventional single junction photovoltaic solar cells under the same conditions.
Key Findings
This information can now be found on Gateway to Research (GtR) http://gtr.rcuk.ac.uk
Potential use in non-academic contexts
This information can now be found on Gateway to Research (GtR) http://gtr.rcuk.ac.uk
Description This information can now be found on Gateway to Research (GtR) http://gtr.rcuk.ac.uk
Date Materialised
Sectors submitted by the Researcher
This information can now be found on Gateway to Research (GtR) http://gtr.rcuk.ac.uk
Project URL:  
Further Information:  
Organisation Website: http://www.shef.ac.uk