Abstract
Carbon quantum dots (CQDs) are particularly sought after for their highly tailorable photoelectrochemical and optical properties. Simultaneously, graphitic carbon nitride (g-C3N4) has also gained widespread attention due to its suitable band gap energy as well as excellent chemical and thermal stabilities. Herein, a novel boron-doped CQD (BCQD) hybridized g-C3N4 homojunction (CN) nanocomposite was rationally engineered and fabricated via a facile hydrothermal route. The optimal photocatalyst sample, 1-BCQD/CN (with a 1:3 mass ratio of boron to CQD) accomplished a Rhodamine B (RhB) degradation efficiency of 97.0 % within 4 hours under low-powered LED light irradiation. The kinetic rate constant of 1.39 x 10-2 min-1 achieved by the optimum sample was found to be 3.6- and 2.8-folds higher than that of pristine CN and un-doped CQD/CN, respectively. Furthermore, 1-BCQD/CN demonstrated remarkable stability, where it retained close to 99.0% of its initial photocatalytic efficiency after three consecutive cycles. The marked improvement in photocatalytic performance of 1-BCQD/CN was attributed to several concomitant factors such as enhanced electron migration from CN to BCQD, suppressed electron-hole recombination and significantly higher charge density in facilitating charge migration. Based on the scavenging tests, it was revealed that the photogenerated holes (h+), superoxide anions (∙O2–) and hydroxyl radicals (∙OH) were the primary reactive species responsible for the photodegradation process. Overall, the highly efficient 1-BCQD/CN composite with excellent photocatalytic activity could provide a cost-effective and robust means for addressing the increasing concerns over global environmental pollution.
Synergistic Effects of The Hybridization Between Boron-Doped Carbon Quantum Dots And n/n-Type g-C3N4 Homojunction For Boosted Visible-Light Photocatalytic Activity