Parwaz Khan Aftab Aslam, Singh Pardeep, Raizada Pankaj, Khan Anish, Asiri Abdullah M, Alotaibi Maha M
Center of Excellence for Advanced Materials Research, King Abdulaziz University, P.O. Box 80203, Jeddah 21589, Saudi Arabia.
School of Advanced Chemical Sciences, Shoolini University, Solan, HP, 173229, India.
Chemosphere. 2023 Mar;316:137839. doi: 10.1016/j.chemosphere.2023.137839. Epub 2023 Jan 11.
In this study graphitic carbon nitride (g-CN or GCN) and phosphorus doped graphitic carbon nitride (p-g-CN or PCN) were prepared using facile thermal polycondensation method. Phosphorus doping was employed to preserve the non-metallic nature of GCN. The AgCl/PCN/FeO heterojunction was synthesized using a simple in-situ route. The photocatalytic performance of the GCN, PCN, FeO and AgCl/PCN/FeO was tested towards 2, 4-dimethylphenol (DMP) pollutant. The work explored improvement in physiochemical properties and reduction of band gap of GCN after P doping (through Tauc's plot method). Coupling with AgCl (silver halide) also enhanced photoinduced charge carriers' separation and migration ability due to apt band alignment among both AgCl and PCN photocatalysts which resulted in formation of direct Z-scheme charge transfer mechanism. Similarly, the incorporation of ferrimagnetic material i.e. FeO enhanced the generation of hydroxyl (OH) radicals via photo-Fenton process and facilitated photocatalysts easy separation from the aqueous medium. Through PL and EIS analysis the enhanced charge separation and migration ability in AgCl/PCN/FeO nanocomposite was validated. The attained DMP degradation efficiency of photo-Fenton assisted AgCl/PCN/FeO/HO Z-scheme nanocomposite was much higher i.e. 99% compared to other photocatalysts within 60 min of visible light irradiation following pseudo-first-order kinetics. Electron paramagnetic resonance (EPR) and scavenging tests confirmed the substantial role of OH and O radicals in the photo-Fenton reaction. Furthermore, liquid chromatography-mass spectrometry (LC-MS) analysis detected the generated oxidative products and mineralization pathways associated with DMP degradation. The proposed direct Z-scheme charge transfer route presented efficient charge separation and migration ability in AgCl/PCN/FeO nanocomposite. Recycle ability of the fabricated AgCl/PCN/FeO photocatalyst was tested up to 5 cycles with 90% removal efficacy, confirming the excellent reusability and stability of AgCl/PCN/FeO photocatalyst.
在本研究中，采用简便的热缩聚法制备了石墨相氮化碳（g-CN或GCN）和磷掺杂石墨相氮化碳（p-g-CN或PCN）。采用磷掺杂来保持GCN的非金属性质。通过简单的原位路线合成了AgCl/PCN/FeO异质结。测试了GCN、PCN、FeO和AgCl/PCN/FeO对2,4-二甲基苯酚（DMP）污染物的光催化性能。该工作探索了磷掺杂后GCN的物理化学性质的改善和带隙的降低（通过陶氏图法）。与AgCl（卤化银）耦合还增强了光生载流子的分离和迁移能力，这是由于AgCl和PCN光催化剂之间合适的能带排列，导致形成直接Z型电荷转移机制。同样，铁磁性材料FeO的掺入通过光芬顿过程增强了羟基（OH）自由基的产生，并促进了光催化剂从水介质中的轻松分离。通过PL和EIS分析验证了AgCl/PCN/FeO纳米复合材料中增强的电荷分离和迁移能力。在可见光照射60分钟后，遵循准一级动力学，光芬顿辅助的AgCl/PCN/FeO/HO Z型纳米复合材料实现的DMP降解效率要高得多，即99%，与其他光催化剂相比。电子顺磁共振（EPR）和清除试验证实了OH和O自由基在光芬顿反应中的重要作用。此外，液相色谱-质谱（LC-MS）分析检测了与DMP降解相关的生成的氧化产物和矿化途径。所提出的直接Z型电荷转移路线在AgCl/PCN/FeO纳米复合材料中表现出高效的电荷分离和迁移能力。制备的AgCl/PCN/FeO光催化剂的循环能力测试了5个循环，去除效率达90%，证实了AgCl/PCN/FeO光催化剂具有优异的可重复使用性和稳定性。
