Development of graphene-based functional interlayers for efficient, stable and inexpensive next generation photovoltaics
This research project is in competition for funding with one or more projects available across the EPSRC Doctoral Training Partnership (DTP). Usually the projects which receive the best applicants will be awarded the funding. Find out more information about the DTP and how to apply.
Start date: 1 October 2019
The aim of this project is to combine the unique advantages of graphene of 1) high charge carrier mobility, 2) good upscalability and 3) barrier effect for water and oxygen ingress to significantly enhance the stability of encapsulation-free perovskite solar cells without compromising solar cell efficiency.
Solar energy is regarded as the cleanest and most reliable energy resource, offering unlimited potential in decarbonising our future energy supply and addressing key societal challenges such as global energy shortage and climate change.
Recently, there has been rapid progress in the development of high performance perovskite solar cells based on solution processed perovskite semiconductors, capable of converting sunlight into electricity highly efficiently. This technology differs from conventional photovoltaics (e.g. silicon) in that it is typically lightweight, flexible, versatile and in-expensive, making them not only a low cost alternative to conventional applications (e.g. rooftops, off-grid charging), but also opening up new applications (e.g. Internet of Things, battery-free electronics).
A critical challenge remaining to be addressed for the commercialisation of perovskite solar cells is their typically limited lifetimes, often associated with a degradation of the light absorbing materials triggered by exposures to environmental oxygen and humidity. This project will address this challenge through the development of solution processed, low defect, transparent and upscalable functional interlayers based on graphene thin films for use in perovskite solar cells.
Project aims and methods
This project will directly build upon the advanced research expertise and facilities already established at Cardiff University in graphene and perovskite solar cell research, comprising three key tasks:
- fabrication of 50-100nm graphene thin films using solution processing methods (e.g. spin coating and printing)
- integration of graphene thin films into benchmark perovskite solar cells
- water/oxygen ingress and stability studies of perovskite solar cells employing graphene interlayers compared to reference cells.
This is a highly multidisciplinary project in which a range of skills and techniques will be developed and used. During the first stage, a number of materials processing (e.g. spin/spray coating, printing) and characterisation (e.g. SEM, FTIR, Raman, AFM) techniques will be used extensively by the candidate for the fabrication and characterisation of graphene thin films. Skills in wet chemistry processing of graphene as well as the optical, chemical and structural analysis of thin films will be developed.
The second stage involves the extensive use of the solar cell fabrication facilities at Cardiff University (PLD, evaporator, sputter), where skills in solar cell fabrication, optimisation and efficiency measurement will be developed.
The final stage of the project will involve the extensive use of the customised solar cell stability infrastructure to understand the degradation mechanisms of perovskite solar cells employing graphene based interlayers, where skills in solar cell stability testing will be developed. The use of graphene as potential barrier layers targeting water and oxygen ingress, a key cause of solar cell instability, has not been previously investigated in the literature. The project will establish extensive collaborations with academic (e.g. Swansea, Imperial, Cambridge) and industrial partners (e.g. Eight19, NSG, Huawei Graphenea, Solennne).