Gezginci E.Hasan M.M.Pehlivan E.Altintas Yildirim O.2026-03-102026-03-1020261369-8001https://doi.org/10.1016/j.mssp.2026.110564https://hdl.handle.net/20.500.13091/13087Chromium-contaminated water is increasingly recognized as a major hidden risk to both the environment and public health due to the extensive industrial use of chromate. This article focuses on the removal of hexavalent chromium (Cr6+) from water solutions using a new type of nanocomposite material (ZrO2@BC-(Css/Ctn)), created by loading ZrO2 nanoparticles onto the surface of carbon-based material derived from Dogwood (Cornus Sanguinea) seed (Css) and chitin (Ctn) biochar structure (BC-(Css/Ctn). This cost-effective composite adsorbent shows promise in efficiently removing Cr6+ from water solutions. Various techniques, such as XRD, FT-IR, SEM, EDX, and UV-vis spectroscopy, were utilized to analyze the structure, morphology, and optics of the all samples. ZrO2 nanoparticles, pristine BC-Css, binary BC-(Css/Ctn) composite and ternary ZrO2@BC-(Css/Ctn) nanocomposite were used as adsorbent and photocatalyst to evaluate the removal activities of Cr6+ from aqueous solutions under UV light irradiation. Integrating ZrO2 photocatalytic nanoparticles on the surface of BC templates combine the advantages of catalytic property of the semiconductor nanoparticles with the adsorbent property of BC. A thorough investigation was conducted into the relevance of nanocomposite in determining the effectiveness of the adsorption and photocatalytic removal of Cr6+. The increased Cr6+ removal performance by ZrO2@BC-(Css/Ctn) was validated by investigations into the impact of various reaction parameters and conditions on the kinetics of Cr6+ removal. It was demonstrated that, under ideal circumstances (50 mg of nanocomposite addition into a 15 ppm Cr6+ solution), the highest Cr6+ removal efficiency was observed with 90.59 ± 0.88% of removal efficiency and a 0.0231 ± 0.0005 min−1 kapp under the UV irradiation. © 2026 Elsevier Ltdeninfo:eu-repo/semantics/closedAccessAdsorptionBiocharChitinDogwoodHexavalent ChromiumNano-Zro2PhotocatalystArticle10.1016/j.mssp.2026.1105642-s2.0-105031441487