This study prepared a biochar-based photocatalyst (Co–Al LDH–C) via facile ultrasonic-assisted solvent treatment. The Co–Al LDH–C photocatalyst shows better photocatalytic activity in CO₂ reduciton than the pure Co–Al LDH without biochar modification. The Co–Al LDH–C affords a CO generation rate of 29.2 µmol g⁻¹. The enhanced CO₂ reduction activity is attributed to the biochar in Co–Al LDH enhanced the light absorption property and separation efficiency of the charge carriers. Additionally, a mechanism insight of Co–Al LDH reduction CO₂ is also investigated by a series of characterizations and experiments results. This work offers a new insight for CO₂ reduction by waste utilization of biomass and improved the performance of Co–Al LDH, and extends the broad potential application of biochar-based photocatalyst in the photocatalytic conversion from solar to carbon resource.

本研究通过简便的超声波辅助溶剂处理制备了一种基于生物炭的光催化剂 (Co-Al LDH-C)。_{Co-Al LDH-C光催化剂在CO 2}还原中的光催化活性优于未经生物炭改性的纯Co-Al LDH。Co-Al LDH-C 的 CO 生成率为 29.2 µmol g ^-1。增强的 CO ₂还原活性归因于 Co-Al LDH 中的生物炭增强了电荷载流子的光吸收特性和分离效率。此外，还通过一系列表征和实验结果研究了Co-Al LDH 还原 CO _{2的机理。}这项工作为 CO _{2提供了新的见解}通过减少生物质的废物利用并提高 Co-Al LDH 的性能，并扩展了生物炭基光催化剂在从太阳能到碳资源的光催化转化中的广泛潜在应用。