Photovoltaic Materials Discovery (PP2.1)
PP2.1: Photovoltaic Materials Discovery
Investigators: Prof. Udo Bach (Monash), Prof. Jacek Jasieniak (Monash), Dr Doojin Vak (CSIRO), Prof. Paul Burn and Dr Paul Shaw (UQ), A/Prof Xiaojing Hao (UNSW), Prof Martin Green (UNSW).
Aims and objectives
The overarching aim of this research is to leverage pioneering, novel materials discovery concepts using experimental and computational high-throughput methodologies and artificial intelligence to fast-track the traditionally very lengthy initial evaluation process for novel thin film PV. Through this approach, the theme will deliver the novel materials required to drive ACAP’s ongoing innovation progress on emerging photovoltaics.
The decarbonisation of the global economy and the growth in photovoltaics are intimately linked. With materials accounting for at least half of clean energy costs, the development of new materials with lower cost, increased photovoltaic performance and enhanced stability has a key role to play in achieving this future.
Emerging solar cell materials, such as lead halide perovskites and organic semiconductors, have the potential to form an important part of the photovoltaic market by offering relatively short energy pay-back times, requiring less energy to synthesise, deposit and recycle, while also providing an opportunity to complement silicon or enhance its performance.
To succeed, emerging materials must demonstrate long-term stability, commercial large-area module efficiency greater than 20%, and be earth-abundant and non-toxic.
From a research perspective, lead halide perovskites and organic semiconductors have been in healthy competition in terms of materials research, with the perovskites leading slightly in efficiency, with organic semiconductor devices having demonstrated lifetimes for commercialisation. The number of possible compositional permutations in these classes of materials is broad, with the diversity providing scope for future improvements of performance and stability through materials design, although with noted challenges of navigating within the huge parameter spaces.
It is worthy to mention that many of the most efficient perovskite devices, and indeed some of the metal chalocogenides, contain toxic heavy metals or scarce materials. For that reason, there is an increased focus on ‘lead-free perovskites’ that is now emerging with the promise of high performance, combined with low toxicity, abundance and improved stability.
The other group of emerging photovoltaic materials are the inorganic adamantines. Among the seven PV materials that have demonstrated an efficiency of >20%, six of these are “closed-shell, adamantine (diamondlike)” semiconductors. While a number of these have been commercialised already, there are increasing efforts on searching for new metal chalcogenide inorganic light harvesting materials that are stable and made from abundant and low/non-toxic constituents.
Research Activities and Plans
There are two key activities within this work package. One will focus on solution-based processing and the other on vacuum-based synthetic/deposition methods that act to accelerate the development of new photovoltaic materials. Application of these towards high-efficiency lead-free perovskites and earth-abundant metal chalcogenides will be a key focus, with a collective target efficiency in this work-package across both material types being >18%. This represents a major increase compared to existing efficiency limits of lead-free perovskites, which are currently at 13% for tin-based systems and only 3% for double-perovskites and also of current emerging earth-abundant kesterites at 13%.