Photocatalytic degradation of chromium by BiVO4-CoPc-nRGO nanocomposite

Background: Photocatalytic degradation has emerged as a promising strategy for eliminating hazardous contaminants from aquatic environments. Chromium (VI) remains a critical pollutant of concern due to its high toxicity and carcinogenic properties, posing significant risks to human health and ecological systems. Advancements in visible-light-responsive photocatalysts offer new avenues for efficient remediation.

Objectives:This study investigates the synthesis, characterization, and photocatalytic performance of a bismuth vanadate–cobalt phthalocyanine–nitrogen-doped reduced graphene oxide (BiVO₄–CoPc–nRGO) nanocomposite for the degradation of C (VI) in water.Methods:The nanocomposite was synthesized through a rapid and cost-effective hydrothermal approach. Structural and morphological assessments were conducted using X-ray diffraction (XRD), scanning electron microscopy (SEM), and complementary analytical techniques to confirm phase composition and surface architecture. Photocatalytic activity was evaluated under visible light irradiation, and reduction efficiency toward Cr (VI) was quantified. Recyclability and operational stability were examined through multiple photocatalytic cycles.

Results:Characterization confirmed the successful formation of a distinct BiVO₄–CoPc–nRGO composite with well-defined structural features conducive to enhanced charge separation and visible-light activity. The material demonstrated high photocatalytic efficiency in reducing Cr (VI), attributable to synergistic interactions among the composite components. Stability tests indicated minimal performance loss across repeated cycles, affirming its robustness and reusability.

Conclusion:The BiVO₄–CoPc–nRGO nanocomposite exhibited strong photocatalytic activity, durability, and operational stability under visible light, underscoring its potential for practical deployment in chromium-contaminated water treatment. The findings provide a foundation for further development of composite photocatalysts for sustainable environmental remediation.