Sea urchin-like ZnO nanoflowers decorated on 3D porous graphene for efficient photocatalytic degradation

Conventional photocatalytic materials, predominantly in powder form, face challenges such as difficulty in recovery and secondary pollution, limiting their practical applications. In this study, a three-dimensional porous graphene framework (3DGF) nanostructure was induced on the surface of polyimide (PI) using laser processing, providing abundant binding sites for zinc oxide (ZnO). By adjusting the laser parameters, 3DGF nanostructures with varying crystallinity and framework characteristics were fabricated, and sea urchin-like ZnO nanoflowers were grown on the surface through a hydrothermal method. Different ZnO morphologies, such as orchid-like nanoflowers and nanorods, were achieved by varying the precursor concentrations. Under UV LED irradiation, 3DGF@ZnO/HMTA (2 : 2) exhibited remarkable photocatalytic degradation efficiencies of 89.62%, 100%, and 92.96% for methylene blue (MB), rhodamine B (RhB), and methyl orange (MO) within 90, 120, and 180 min, respectively. After multiple cycles of RhB photodegradation, the efficiency remained at 96.53%, and even after 20 tape adhesion tests, the photocatalytic degradation efficiency for RhB was sustained at 89.81%. The superior performance and stability highlight the potential of 3DGF@ZnO/HMTA for sustainable water pollution remediation.