Biochar Produced from Dead Pine Needles to Produce Biochar/CuO and Biochar/CuO/BaO for Water and Biomedical Remediation

The sustainable utilization of biomass waste for environmental applications has gained significant interest in recent years. This study explores the synthesis of biochar-based metal oxide composites, Biochar/CuO and Biochar/CuO/BaO, using biochar derived from the pyrolysis of dead pine needles, an abundant forest residue. Copper oxide (CuO) and barium oxide (BaO) were integrated into the biochar matrix to enhance its photocatalytic and antimicrobial properties. The prepared composites were characterized using X-ray diffraction (XRD), ultraviolet-visible spectroscopy (UV-Vis), Fourier-transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM) to confirm their crystallinity, optical behavior, functional groups, morphology, and elemental composition. The Biochar/CuO and Biochar/CuO/BaO composites exhibited superior photocatalytic activity, achieving significant degradation of methylene blue dye under visible light irradiation, attributed to the synergistic effects of biochar’s high surface area and the metal oxides’ semiconductor properties. Additionally, the composites demonstrated potent antibacterial activity against Enterococcus faecalis, a gram positive bacteria, owing to the generation of reactive oxygen species. These findings highlight the potential of pine needle-derived biochar-metal oxide composites as cost-effective, eco-friendly materials for dye degradation and microbial control. This work contributes to the valorization of forest waste and the development of multifunctional nanomaterials for environmental remediation and public health applications.