Biomass-based carbon quantum dots for polycrystalline silicon solar cells with enhanced photovoltaic performance

Polycrystalline silicon solar cells modified using biomass resources are promising candidates to accomplish the goal of carbon neutrality. Developing a device with high power conversion efficiency (PCE) is important to resolve the ever-increasing energy shortage issues. Therefore, we develop a facile solution-casting approach to synthesise ethylene-vinyl acetate (EVA) films modified with ultra-high fluorescent carbon quantum dots (CQDs). The films were coated on the surface of polycrystalline silicon solar cells and the PCE increased from 13.19% to 13.65%. The ultra-high fluorescent CQDs were prepared from Ginkgo biloba via a hydrothermal process, and different parts of Ginkgo biloba-based CQDs were investigated in various conditions. The ultra-high fluorescent CQDs obtained at 180 °C, 8 h and a reaction concentration of 0.048 g/mL from Ginkgo wood resulted in high fluorescence of up to 976.74 a.u.. At an excitation wavelength of 365 nm. This work substantially expands the potential of EVA films containing ultra-high fluorescent CQDs for applications in the photovoltaic, environment and energy fields. •A facile solution-casting approach was utilised to synthesise CQDs/EVA films.•Ultra-high fluorescent CQDs were synthesised via hydrothermal processes.•Ginkgo wood has higher fluorescent properties than bark and leaf.•The CQDs/EVA films show high photovoltaic efficiency of 13.61%.•The CQDs/EVA films can potentially be used as photovoltaic materials.