Despite its current predominance in the photovoltaics (PV) energy market, silicon is being gradually complemented with other photovoltaic materials, able to simplify the production processes, lower the costs, as well as improve the overall efficiency performance. Among these new materials, perovskites can lead to solar cells with a very high efficiency (33.7% ESTI certified efficiency in May 2023[1]), These results have attracted major interest and significant investments toward their industrial scale-up.

Nevertheless, as perovskite solar cells (PSC) electrical properties vary over time due to various meta-stability related factors (material diffusion, chemical imbalance as well as temperature, measurement set-up, light and/or voltage bias triggers..), repeatability of the I-V curve is not always granted, and many uncertainties related to the PSC characterization process are still under scrutiny. In fact, for PSC at present there is not one recognized evaluation technique grounded on international standards yet.

Additionally, PSC contain compounds that require very accurate handling ways, either due to their tangible health-hazard nature or because they can still be considered valuable for the new production chain. These observations raise the need to develop an effective material recovery/recycle strategy to reduce the life cycle impact of this technology before it hits industrial scale production.

The Joint Research Center (JRC) of the European Commission is currently carrying on the “Recycle-PSC” project (Evaluation, assessment and improvement of Process for Recycling and Reusing Innovative). Recycle PV focuses on both aspects of the measurement and characterization of PSC, as well as on the assessment and improvement of certain recycling processes to recover and reuse the materials comprising a PSC, with the aim of developing a safe and sustainable protocol to measure and handle these devices.

From the characterization side, we are exploring ways to work around the Maximum Power Point Tracking routine currently applied at ESTI [2], in order to optimize measurement time and measurement accuracy. The rationale behind it, is that the highly time consuming measurement procedure currently applied, is considered to not be feasible in the long term, as an accurate up-scaled screening protocol of PSC. From the recycling perspective instead, we concentrated on the glass substrate as the most promising and suitable component to recover, thanks to its high market value, strong physio-chemical stability and ease of processing. Compared to the common results reported so far in the specific literature of the field, which focused on the use of hazardous solvents like DMF, i here we report the use of acetone as a non-hazardous and inexpensive solvent to recover the substrate from PSC, thus potentially reducing the environmental impact of the whole process.

Results achieved at the JRC aim to contribute to the development of future policies regarding the large-scale implementation of PSC as high-efficiency and low-cost PVs.

[1] https://www.pv-magazine.com/2023/05/30/kaust-claims-33-7-efficiency-for-perovskite-silicon-tandem-solar-cell/

[2] Giorgio Bardizza et al 2021 J. Phys. Energy 3 021001