Department of Chemistry, National Institute of Technology, Silchar, 788010, Assam, India.
Department of Environmental Science, Parul Institute of Applied Sciences, Parul University, Vadodara, 391760, Gujarat, India.
Sci Rep. 2024 Oct 8;14(1):23493. doi: 10.1038/s41598-024-74819-1.
The present study focuses on the green synthesis of a novel Z-scheme SnS₂/HAp photocatalyst using Ocimum tenuiflorum (tulsi) leaf extract as a stabilizing agent. This approach not only emphasizes sustainability but also adds value to waste by extracting hydroxyapatite (HAp) from Labeo rohita fish scales, addressing the challenge of their disposal. The synthesized photocatalyst was thoroughly characterized using a range of analytical techniques to evaluate its crystal structure, optical properties, morphology, and elemental composition. The photocatalytic activity of the SnS₂/HAp composite was assessed through the degradation of gentian violet (GV) dye, a representative organic pollutant. Various reaction parameters were optimized to enhance the degradation efficiency, and the photocatalyst's performance was further tested across different water matrices. Under optimal conditions, the SnS₂/HAp photocatalyst achieved a maximum photodegradation efficiency of 97.49% with a rate constant of 0.0494 min for GV dye. Additionally, it exhibited an efficiency greater than 70% against other emerging pollutants via advanced oxidation processes (AOP). The enhanced photocatalytic activity was attributed to the formation of a Z-Scheme heterojunction between SnS and HAp, which enhanced the charge separation efficiency and delayed the charge recombination. The study also demonstrated the photocatalyst's remarkable reusability, maintaining high performance over five cycles and across various water environments. This highlights its potential as a sustainable solution for the removal of organic pollutants from aqueous streams. Finally, a Z-scheme electron transport mechanism is proposed to explain the photodegradation process of GV dye using the SnS₂/HAp photocatalyst.
本研究聚焦于使用罗非鱼鳞片中提取的羟磷灰石（HAp）作为稳定剂，通过荜茇（ Ocimum tenuiflorum ，即“印度薄荷”）叶提取物绿色合成新型 Z 型 SnS₂/HAp 光催化剂。这种方法不仅强调可持续性，还通过从罗非鱼鳞片中提取羟磷灰石（HAp）来解决废物处理的问题，使废物再利用。使用一系列分析技术对合成的光催化剂进行了全面表征，以评估其晶体结构、光学性质、形态和元素组成。通过评估对龙胆紫（GV）染料的降解来评估 SnS₂/HAp 复合材料的光催化活性，这是一种代表性的有机污染物。优化了各种反应参数以提高降解效率，并在不同的水基质中进一步测试了光催化剂的性能。在最佳条件下，SnS₂/HAp 光催化剂对 GV 染料的最大光降解效率达到 97.49%，速率常数为 0.0494 min。此外，它通过高级氧化工艺（AOP）对其他新兴污染物的效率大于 70%。增强的光催化活性归因于 SnS 和 HAp 之间形成 Z 型异质结，这提高了电荷分离效率并延迟了电荷复合。该研究还证明了光催化剂的出色可重复使用性，在五个循环和各种水环境中均保持高性能。这突出了它作为从水相中去除有机污染物的可持续解决方案的潜力。最后，提出了一种 Z 型电子传输机制来解释使用 SnS₂/HAp 光催化剂对 GV 染料的光降解过程。
