EPSRC logo

Details of Grant 

EPSRC Reference: EP/T01119X/1
Title: Next Generation Perovskite Solar Cell Structures
Principal Investigator: Harwell, Dr J
Other Investigators:
Researcher Co-Investigators:
Project Partners:
Department: Physics and Astronomy
Organisation: University of St Andrews
Scheme: EPSRC Fellowship
Starts: 04 November 2019 Ends: 03 November 2022 Value (£): 319,254
EPSRC Research Topic Classifications:
Solar Technology
EPSRC Industrial Sector Classifications:
Energy
Related Grants:
Panel History:
Panel DatePanel NameOutcome
16 Sep 2019 Engineering Fellowship Interview Panel 17 and 18 September 2019 Announced
06 Aug 2019 Engineering Prioritisation Panel Meeting 6 and 7 August 2019 Announced
Summary on Grant Application Form
With the UK government's target to reduce carbon emissions by 80 % by 2050, there is more demand than ever for renewable energy. Solar photovoltaics can directly harness the power of the sun (our most abundant source of renewable energy) by turning light into electricity. Photovoltaics are one of the most attractive sources of renewable energy because they can provide clean electricity on small or large scales with minimal impact on the local environment. The main form of photovoltaic cells used commercially are silicon solar cells.

Perovskite solar cells (PSCs) are an exciting new class of solar cell which have the potential to be flexible, thinner, and cheaper than silicon solar cells while achieving a similar efficiency with a lower energy cost of manufacture. I aim to improve the potential of PSCs even further by altering their design to a "back-contact" structure that could increase their performance whilst reducing material costs and making it easier to optimise their operation. A PSC is made from 3 key parts - an absorber for turning light into electricity, and two contacts for extracting the charge. In a normal solar cell these layers are stacked on top of each other like a sandwich, with the absorber in the middle. This means that light has to pass through the top layer of the sandwich in order to reach the absorber, meaning some of it is lost unless the top layer is made from very expensive materials which are both transparent and conductive. A back-contact cell overcomes this by having both contacts on the bottom of the absorber in a honeycomb pattern, or as a set of fingers interwoven with each other. This leaves the top of the absorber free to absorb light with no other layers getting in the way.

The back-contact structure has lots of advantages over the standard way of making PSCs, but it has not been studied in detail so far because it is harder to make than the standard structure. The interlocking metal fingers in a back-contact PSC must be thinner than a hundredth of the width of a human hair, whilst covering areas in the order of square meters. Because of this, nobody has been able to do this in a cost effective or scalable way so far. Perovskite lasers are frequently made diffraction gratings, which have very similar structures to the patterns needed in a back-contact solar cell, using a process called nanoimprint lithography. This involves making a stamp in the desired pattern and then physically pressing the features into the material. This is a cheap process which can make patterns quickly over large areas, and in this project I will adapt this technique for perovskite solar cells instead of diffraction gratings. This will enable efficient back-contact PSCs on large areas using a technique that could easily be scaled industrially.

Enabling the easy production of back-contact PSCs could help make PSCs with higher efficiency than the sandwich structure, whilst simultaneously reducing their material costs and removing several design constraints. A back-contact cell also enables studies of the physics of the absorber materials which are impossible in the sandwich structure. These experiments will greatly enhance our understanding of how PSCs work, and will speed up research to help find new and improved materials which achieve even higher efficiency. This could help solar power compete with or even become cheaper than fossil fuels, thus paving the way for a new revolution in green energy.

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
Impacts
Description This information can now be found on Gateway to Research (GtR) http://gtr.rcuk.ac.uk
Summary
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.st-and.ac.uk