Bi-Based Z-Scheme Nanomaterials for the Photocatalytic Degradation of Organic Dyes

A multicomponent Bi-based Z-scheme photocatalyst, BISB, was developed through a hydrothermal method. In this sample, two semiconducting nanostructures, BiOI and Bi2S3, were linked together with the metal Bi nanoparticle. As compared with BiOI (BI) and heterojunction BiOI/Bi2S3 (BIS) samples, the BISB had optimal Rhodamine B (RhB) photodecomposition performance. High efficiency separation of photoexcited electrons and holes, decreased band gap energy, extended specific surface area, and promotional redox potential were key factors for enhancing the photocatalytic activity of the prepared sample. The photoexcited holes were the key active radicals during the RhB photodecomposition process over the BISB catalyst, while center dot O-2 was also involved to a smaller extent. Additionally, the photocatalyst demonstrated excellent reusability and stability during the photoreaction process, suggesting that the BISB sample could be a candidate for water purification applications.

通过水热法制备了一种多组分铋基Z型光催化剂BISB。在该样品中，两种半导体纳米结构BiOI和Bi₂S₃通过金属铋纳米粒子连接在一起。与BiOI（BI）和异质结BiOI/Bi₂S₃（BIS）样品相比，BISB具有最佳的罗丹明B（RhB）光降解性能。光生电子和空穴的高效分离、带隙能降低、比表面积增大以及氧化还原电位提高是所制备样品光催化活性增强的关键因素。在BISB催化剂上RhB光降解过程中，光生空穴是关键的活性自由基，同时·O₂⁻也有较小程度的参与。此外，该光催化剂在光反应过程中表现出优异的可重复使用性和稳定性，这表明BISB样品可作为水净化应用的候选材料。