Printed Solar Cells on Steel

Tata Steel would like to understand the potential of adding photoactive energy generation materials to a portfolio of steel products to achieve added value. This entails the sequential deposition of functional layers onto pre-existing architectural products culminating in a completed photovoltaic product appropriate for direct integration into the built environment.

The proposed technology of choice is that of the perovskite solar cell. Perovskite solar cells (PSCs) as solid state devices have demonstrated the highest efficiency of all printed solar cell technologies. The current record for a small area PSC now stands at 25 %. These small area devices are often processed with an evaporated gold or silver top electrode which can add significantly to the cost of the devices and render the device stack inappropriate for mounting onto an opaque substrate. This means that generally speaking most perovskite cell architectures are inappropriate for metal or steel based substrates. The world's first perovskite solar cell made using a metal substrate was developed and published by Swansea University (see Troughton et al, Highly efficient, flexible, indium-free perovskite solar cells employing metallic substrates, J Mat Chem A 2015, 3, 9141). There are two possible approaches for deploying a PV product onto a steel substrate:

1. Direct application of layers sequentially onto the metal itself, whereby the metal substrate acts as an electrode in the device stack. This could be a metal foil material that is then subsequently laminated to a more appropriate architectural steel.

2. Application of an electrically insulating layer to an organically coated steel product that is then further functionalised with an electrically conducting layer and then sequentially applied photoactive materials. The device is then completed with a transparent conducting layer and barrier film.

The research will involve consideration of these approaches and collaboration with the existing research team to develop a pathway to a printed solar cell demonstrator on steel substrates.

The CDT will produce 50 graduates with doctoral level knowledge and research skills focussed on the development and manufacture of functional industrial coatings. Key impact areas are:

Knowledge
- The development of new products and processes to address real scientific challenges existing in industry and to transfer this knowledge into partnering companies. The CDT will enable rapid knowledge transfer between academia and industry due to the co-created projects and co-supervision.
- The creation of knowledge sharing network for partner companies created by the environment of the CDT.
- On average 2-3 publications per RE. Publications in high impact factor journals. The scientific scope of the CDT comprises a mixture of interdisciplinary areas and as such a breadth of knowledge can be generated through the CDT. Examples would include Photovoltaic coatings - Journal of Materials Chemistry A (IF 8.867) and Anti-corrosion Coatings - Corrosion Science (IF 5.245), Progress in Organic Coatings (IF 2.903)
- REs will disseminate knowledge at leading conferences e.g. Materials Research Society (MRS), Meetings of the Electrochemical Society, and through trade associations and Institutes representing the coatings sector.
- A bespoke training package on the formulation, function, use, degradation and end of life that will embed the latest research and will be available to industry partners for employees to attend as CPD and for other PGRs demonstrating added value from the CDT environment.

Wealth Creation
- Value added products and processes created through the CDT will generate benefits for Industrial partners and supply chains helping to build a productive nation.
- Employment of graduates into industry will transfer their knowledge and skills into businesses enabling innovation within these companies.
- Swansea University will support potential spin out companies where appropriate through its dedicated EU funded commercialisation project, Agor IP.

Environment and society
- Functionalised surfaces can potentially improve human health through anti-microbial surfaces for health care infrastructure and treatment of water using photocatalytic coatings.
- Functionalised energy generation coatings will contribute towards national strategies regarding clean and secure energy.
- Responsible research and innovation is an overarching theme of the CDT with materials sustainability, ethics, energy and end of life considered throughout the development of new coatings and processes. Thus, REs will be trained to approach all future problems with this mind set.
- Outreach is a critical element of the training programme (for example, a module delivered by the Ri on public engagement) and our REs will have skills that enable the dissemination of their knowledge to wide audiences thus generating interest in science and engineering and the benefits that investments can bring.

People
- Highly employable doctoral gradates with a holistic knowledge of functional coatings manufacture who can make an immediate impact in industry or academia.
- The REs will have transferable skills that are pertinent across multiple sectors.
- The CDT will develop ethically aware engineers with sustainability embed throughout their training
- The promotion of equality, diversity and inclusivity within our cohorts through CDT and University wide initiatives.
- The development of alumni networks to grow new opportunities for our CDT and provide REs with mentors.