Quantum accessory for solar panels: a sustainable solution to improve energy efficiency based on the circular economy

Carbon quantum dots (CQDs) have emerged as promising spectral modifiers for photovoltaic devices due to their photoluminescent down-conversion properties. In parallel, silica-rich industrial residues represent an environmental liability but also a potential source of functional materials. This study investigated the valorization of SiO2-rich mining residue for the production of a sodium silicate matrix incorporating CQDs as a spectral conversion overlayer for solar panels. The treated residue successfully yielded sodium silicate, and CQDs were synthesized and integrated into the matrix. Photovoltaic testing demonstrated that panels coated with industrial-derived sodium silicate exhibited an initial efficiency increase of 8.91% compared to standard panels. However, coatings containing CQDs with the residue-derived sodium silicate showed reduced performance in early-stage testing, and all samples exhibited progressive opacity after six months, indicating limited long-term stability. These findings highlight both the potential and the challenges of integrating CQD-based spectral management with mining residue valorization. While the approach demonstrates feasibility in short-term performance enhancement, material stability remains a critical barrier for practical implementation.