Enhanced optical properties of luminescent solar concentrators via metal ion doping in carbon dots

Abstract

Luminescent solar concentrators (LSCs) utilizing carbon dots (CDs) have emerged as promising solutions for transparent photovoltaic applications due to their high transparency and efficient light-to-electricity conversion. This study investigates the synthesis and optical enhancement of CDs doped with transition metal ions—cobalt, nickel, copper, and zinc—to improve LSC performance. Using a microwave synthesis method, we produced CDs with a high quantum yield of 81%, a substantial Stokes shift of 0.71 eV, and excellent stability. Doping CDs with metal ions at molar concentrations of 1%, 3%, and 5% revealed that 1 mol% copper-doped CDs exhibited superior optical properties, enhancing light absorption and emission through effective metal-ion interactions. LSCs, fabricated with dimensions of 15 × 15 × 0.6 cm³ using glass and PMMA waveguides, achieved notable photovoltaic performance with an optical efficiency of 3.99% and a photoconversion efficiency (PCE) of 1.45% for PMMA-based devices. The introduction of copper at 1% concentration resulted in a 22% increase in both optical efficiency and PCE. Stability assessments over 90 days indicated minimal performance degradation, underscoring the robustness of the synthesized materials. This research highlights the potential of metal-doped CDs to optimize LSC technology, facilitating integration into urban environments and advancing the commercialization of transparent photovoltaic systems.