Abstract：
The rational design of Z-scheme heterojunction hybrid photocatalysts is considered a promising way to achieve high photocatalytic activity. In this study, a dual Z-scheme heterojunction with bismuth sulfide (Bi2S3) nanorods and bismuth oxide (Bi2O3) nanoparticles anchored Sulfur-doped carbon nitride (S-CN) nanotubes (Bi2S3/S-CN/Bi2O3) is designed and fabricated through the ordinal metal ion adsorption, pyrolysis, and sulfidation processes using supramolecular rods as precursor. Compared with pristine Bi2S3, Bi2O3, and CN, the dual Z-scheme tube-shaped Bi2S3/S-CN/Bi2O3 catalyst exhibited a significantly improved photocatalytic activity in amine oxidation. The optimized Bi2S3/S-CN/Bi2O3 nanostructure exhibits a 97.6 % benzylamine conversion and 99.4 % imine selectivity within 4 h under simulated solar light irradiation. The excellent activity of Bi2S3/S-CN/Bi2O3 nanotubes can be attributed to the characteristic hollow defect band structure and efficient charge separation and transfer achieved by the dual Z-scheme charge transfer mechanism, which was systematically studied using electron spin resonance spectroscopy, Kelvin probe force microscope, and other techniques. The optimized dual Z-scheme heterojunction hybrid photocatalyst maintains the high oxidizing ability of Bi2S3 and Bi2O3 and the excellent reducing ability of CN, thereby significantly enhancing the photocatalytic activity. This research provides a facile and feasible synthesis strategy for designing dual Z-scheme heterojunctions with defect band structure to improve the photocatalytic activity.
摘要：
Z方案异质结混合光催化剂的合理设计被认为是实现高光催化活性的有希望的方法。在这项研究中,通过顺序金属离子吸附，设计并制造了具有硫化铋（Bi2S3）纳米棒和氧化铋（Bi2O3）纳米颗粒锚定的硫掺杂氮化碳（S-CN）纳米管（Bi2S3/S-CN/Bi2O3）的双Z方案异质结，热解,和使用超分子棒作为前体的硫化过程。与原始Bi2S3，Bi2O3和CN相比，双Z型管状Bi2S3/S-CN/Bi2O3催化剂在胺氧化中表现出显著提高的光催化活性。在模拟太阳光照射下，优化的Bi2S3/S-CN/Bi2O3纳米结构在4h内表现出97.6%的苄胺转化率和99.4%的亚胺选择性。Bi2S3/S-CN/Bi2O3纳米管的优异活性可以归因于双Z方案电荷转移机制所实现的特征中空缺陷带结构和高效的电荷分离和转移，使用电子自旋共振谱系统研究，开尔文探针力显微镜，和其他技术。优化的双Z方案异质结复合光催化剂保持了Bi2S3和Bi2O3的高氧化能力和CN的优异还原能力，从而显著提高光催化活性。该研究为设计具有缺陷能带结构的双Z型异质结以提高光催化活性提供了一种简便可行的合成策略。
