Assessing aspects of solution-based chemical synthesis to convert waste Si solar cells into nanostructured aluminosilicate crystals

• Published in: CrystEngComm Vol. 26; no. 17; pp. 2233 - 224
• Main Authors: Garskaite, Edita, Bollen, Math, Mulenga, Enock, Warlo, Mathis, Bark, Glenn, Olsen, Espen, Brazinskiene, Dalia, Sokol, Denis, Buck, Dietrich, Sandberg, Dick
• Format: Journal Article
• Language: English
• Published: Cambridge Royal Society of Chemistry 29.04.2024
• Subjects: Aluminosilicates; Aluminum silicates; Chemical composition; Chemical synthesis; Crystals; CT scan; Earth and Related Environmental Sciences; Electric Power Engineering; Elkraftteknik; End of life; Environmental Sciences; Full-field data; Geovetenskap och miljövetenskap; Image processing; Low temperature; Malmgeologi; Miljövetenskap; Minerals; Moisture simulation; Mould estimation; Multivariate modelling; Nanostructure; Natural Sciences; Naturvetenskap; Ore Geology; Phase composition; Photovoltaic cells; Room temperature; Silicon; Solar cells; Temperature dependence; Träteknik; Waste utilization; Wood Science and Engineering; X-ray fluorescence
• ISSN: 1466-8033; 1466-8033
• DOI: 10.1039/d4ce00038b

The end-of-life recycling of crystalline silicon photovoltaic (PV) modules and the utilisation of waste is of fundamental importance to future circular-economy societies. In the present work, the wet-chemistry synthesis route - a low-temperature dissolution-precipitation process - was explored to produce aluminosilicate minerals from waste c-Si solar cells. Nanostructured crystals were produced in an alkaline medium by increasing the reaction temperature from room temperature to 75 °C. The morphology of the produced crystals varied from nanolayered aggregates to rod-shaped crystals and was found to be dependent on the temperature of the reaction medium. Chemical and phase composition studies revealed that the synthesised compounds consisted of structurally different phases of aluminosilicate minerals. The purity and elemental composition of produced crystals were evaluated by energy dispersive spectroscopy (EDS) and micro X-ray fluorescence (μXRF) analysis, confirming the presence of Al, O, and Si elements. These results give new insights into the processing of aluminosilicate minerals with sustainable attributes and provide a possible route to reducing waste and strengthening the circular economy. An affordable, scalable, and easily adoptable solution-based processing route provides a potential way of converting waste Si solar cells into aluminosilicate minerals to contribute to sustainability in the solar energy value chain.