School of Chemistry and Environmental Engineering, Yancheng Teachers University, Yancheng, Jiangsu Province, 224051, China.
School of Chemistry and Environmental Engineering, Yancheng Teachers University, Yancheng, Jiangsu Province, 224051, China.
J Hazard Mater. 2020 Mar 5;385:121508. doi: 10.1016/j.jhazmat.2019.121508. Epub 2019 Oct 24.
Z-scheme heterojunction can not only promote the separation of photogenerated carriers, but also retain the strong redox potential of the system, which would greatly improve the photocatalytic performance of catalyst. Herein, a Z-scheme AgI/BiVO heterojunction photocatalyst was prepared by a hydrothermal process combined with in situ coprecipitation process. Multiple techniques were employed to investigate the morphology, composition, chemical and electronic properties of the as-prepared samples. The obtained Z-scheme AgI/BiVO heterojunction photocatalyst exhibited remarkably enhanced photocatalytic performance towards sulfamethazine (SMZ) degradation under visible light irradiation. Especially, the 20 wt% AgI/BiVO composites exhibited the highest photocatalytic activity for sulfamethazine (SMZ) degradation and 91.47% SMZ would be eliminated within 60 min. In comparison with NO and SO, the presence of Cl and HCO presented more obviously inhibition effects on SMZ degradation. The possible degradation pathways of SMZ were speculated by identifying degradation intermediates. O, h and OH all involved in the photocatalytic degradation SMZ. The highly enhanced photocatalytic performance might be attributed to form Z-scheme junction between AgI and BVO, which are conducive to the efficient charges separation and maintain high redox potential. This work enriches BiVO-based Z-scheme heterojunction photocatalytic system and provides a reference for the preparation of effective Z-scheme junction photocatalysts.
Z 型异质结不仅可以促进光生载流子的分离，而且可以保留体系的强氧化还原电位，从而大大提高催化剂的光催化性能。本文通过水热法结合原位共沉淀法制备了 Z 型 AgI/BiVO 异质结光催化剂。采用多种技术对所制备样品的形貌、组成、化学和电子性质进行了研究。所获得的 Z 型 AgI/BiVO 异质结光催化剂在可见光照射下对磺胺甲恶唑（SMZ）的降解表现出显著增强的光催化性能。特别是，20wt%AgI/BiVO 复合材料对磺胺甲恶唑（SMZ）的降解表现出最高的光催化活性，在 60min 内可消除 91.47%的 SMZ。与 NO 和 SO 相比，Cl 和 HCO 的存在对 SMZ 降解表现出更明显的抑制作用。通过鉴定降解中间体推测了 SMZ 的可能降解途径。O、h 和 OH 均参与了 SMZ 的光催化降解。高增强的光催化性能可能归因于 AgI 和 BVO 之间形成 Z 型结，有利于高效电荷分离并保持高氧化还原电位。这项工作丰富了基于 BiVO 的 Z 型异质结光催化体系，并为制备有效的 Z 型结光催化剂提供了参考。
