The development of efficient photocatalytic electrodes holds immense
promise for addressing environmental challenges. This study investigates the
enhanced photocatalytic activity of a microwave-synthesized hybrid
nanocomposite, emphasizing its potential contribution to sustainable
environmental remediation efforts. A hybrid nanocomposite is synthesized via
a one-pot microwave-based method, combining carbon nanodots (CNDs) and
zinc oxide nanoparticles (ZnO NPs) for methylene blue photodegradation.
The CNDs are synthesized from D-glucose precursor with a yield of 17.3%,
while ZnO NPs have a higher yield of 27.7%. The hybrid (ZnO/CNDs) is
formed with a 24.4% yield, leading to a size over 60 nm, indicating successful
adsorption of CNDs on ZnO surfaces. This hybridization improves
photocatalytic properties, decreasing the bandgap from 3 to 2.1 eV, and
enhancing visible light photocatalysis. Furthermore, thin film electrodes of
ZnO and hybrid materials are prepared on glass slides by spin coating. The
hybrid electrode demonstrates a 70% degradation efficiency of methylene
blue, surpassing ZnO (59%) after 120 min of light exposure. Its rate constant
is 0.01162 min−1 compared to ZnO’s 0.00943 min−1, with an apparent
quantum yield of 0.023 (hybrid) versus 0.019 (ZnO). Stability tests confirms
sustained efficiency over multiple cycles, highlighting the electrodes’
environmental and economic benefits in sustainable photodegradation
applications.
