The new ultra-thin solar cell could become a cost-effective, environmentally friendly and non-toxic alternative to current solar energy technology, considering that the standard solar cells depend on toxic elements, like lead, or rare elements, like indium, needed to make it.
In the study published in the journal “Nature Photonics”, the researchers describe how they improve the energy efficiency of a new type of photovoltaic cell, made from nanocrystals containing silver and bismuth atoms. In addition, these 30-nm-thick, environmentally friendly cells achieved an energy conversion efficiency of 9.17%, in other words, from the energy generated by sunlight 19.17% was converted into electricity.
During the tests, the cells also maintained high stability under different environmental conditions, suggesting less degradation of the cells over long periods.
The bismuth-based nanocrystals are not only made of non-toxic and naturally abundant elements they are also cheap to produce. According to the researchers, the photovoltaic cell material is ten to the solar cell is ten to fifty times thinner than current photovoltaic instruments. It is also a thousand times thinner than silicon photovoltaic instruments, which are bulky, expensive and require a lot of energy to manufacture.
The goal is to further improve efficiency to be comparable with silicon-based solar cells. The increase in efficiency of PV cells achieved so far has been supported by European funds (HEINSOL, PREBIST and DISCOVER).
Cordis.europa.eu. 2022. CORDIS | European Commission. [online] Available at: <https://cordis.europa.eu/article/id/435773-the-new-ultra-thin-solar-cell-low-cost-non-toxic-and-more-efficient/es> [Accessed 16 March 2022].
UCL News. 2022. New efficiency record set for ultrathin solar cells. [online] Available at: <https://www.ucl.ac.uk/news/2022/feb/new-efficiency-record-set-ultrathin-solar-cells> [Accessed 16 March 2022].