<p>Carbon quantum dots are gaining attention as eco-friendly materials due to their unique properties. However, the scalability of their production is hindered by the complex separation techniques and the involvement of various chemicals in the process. The potential of cellulose was explored for the first time; by successfully converting post-consumer cotton waste to carbon quantum dots by the hydothermal technique. This process is free from toxic chemicals and achieved in a short synthesis time through solvent-induced precipitation and filtration methods. The structural and morphological characteristics as well as the particle size of synthesized carbon quantum dots were evaluated through FTIR, TEM, SEM, and XRD. The as-synthesized carbon quantum dots were loaded on cotton fabric, and cationized before loading for durable functionality. The study evaluated the electrokinetic potential to assess surface charge following the cationization process. To confirm the successful application of carbon quantum dots on cotton fabric, FTIR and TEM analyses were conducted. The treated fabric demonstrated a UV protection factor (UPF) exceeding 50 and exhibited antibacterial efficacy against <i>S. aureus</i>, with over 90% effectiveness both qualitatively and quantitatively, maintaining strong antibacterial properties even after 10 washing cycles. Thus, this research proposes a facile, economical, and environmentally sustainable approach for developing multifunctional textiles through the application of carbon quantum dots.</p> Graphical abstract <p></p>