Ding Chengli, Zhao Huanhuan, Zhu Xiao, Liu Xiaoling
Key Laboratory of Coal Cleaning Conversion and Chemical Engineering Process, Xinjiang Uygur Autonomous Region, Xinjiang University, Urumqi 830046, China.
Nanomaterials (Basel). 2022 Jun 11;12(12):2021. doi: 10.3390/nano12122021.
At present, the research focus has been aimed at the pursuit of the design and synthesis of catalysts for effective photocatalytic degradation of organic pollutants in wastewater, and further exploration of novel materials of the photodegradation catalyst. In this paper, the Sol-gel route after thermal treatment was used to produce NiFeO carbon aerogel (NiFeO-CA) nanocomposites with cotton linter cellulose as the precursor of aerogel, by co-precipitating iron and nickel salts onto its substrate. The structure and composition of these materials were characterized by X-ray diffraction (XRD), energy dispersive spectroscopy (EDS), Raman spectra, high-resolution scanning electron microscopy (HR-SEM), high-resolution scanning electron microscope mapping (SEM-mapping), X-ray photoelectron spectroscopy (XPS) and Brunauer-Emmett-Teller (BET)'s surface area. The magnetic properties of the material were analyzed by a vibrating-sample magnetometer (VSM). Moreover, diffuse reflectance spectra (DRS), electrochemical impedance spectroscopy (EIS) and photo-luminescence spectroscopy (PL) characterized the photoelectric properties of this cellulose-aerogels-based NiFeO-CA. Methylene blue (MB) acted as the simulated pollutant, and the photocatalytic activity of NiFeO-CA nanocomposites under visible light was evaluated by adjusting HO content and the pH value. The results showed that the optical absorption range of nickel ferrite was broadened by doping cellulose-aerogels-based carbon, which exerted more positive effects on photocatalytic reactions. This is because the doping of this aerogel carbon promoted a more uniform distribution of NiFeO particles. Given the Methylene blue (MB) degradation reaction conformed to the first-order kinetic equation, the NiFeO-CA nanocomposites conducted excellent catalytic activity by maintaining almost 99% of the removal of MB (60 mg/L) within 180 min and upheld excellent stability over four consecutive cycles. This study indicated that NiFeO-CA nanocomposites reserved the potential as a future effective treatment of dye wastewater.
目前，研究重点一直致力于设计和合成用于有效光催化降解废水中有机污染物的催化剂，并进一步探索光降解催化剂的新型材料。本文采用热处理后的溶胶-凝胶法，以棉短绒纤维素为气凝胶前驱体，通过将铁盐和镍盐共沉淀在其基体上制备了NiFeO碳气凝胶（NiFeO-CA）纳米复合材料。通过X射线衍射（XRD）、能谱（EDS）、拉曼光谱、高分辨率扫描电子显微镜（HR-SEM）、高分辨率扫描电子显微镜映射（SEM-映射）、X射线光电子能谱（XPS）和布鲁诺尔-埃米特-泰勒（BET）表面积对这些材料的结构和组成进行了表征。通过振动样品磁强计（VSM）分析了材料的磁性。此外，漫反射光谱（DRS）、电化学阻抗谱（EIS）和光致发光光谱（PL）表征了这种基于纤维素气凝胶的NiFeO-CA的光电性能。以亚甲基蓝（MB）作为模拟污染物，通过调节羟基自由基（·OH）含量和pH值评估了NiFeO-CA纳米复合材料在可见光下的光催化活性。结果表明，掺杂基于纤维素气凝胶的碳拓宽了镍铁氧体的光吸收范围，对光催化反应产生了更积极的影响。这是因为这种气凝胶碳的掺杂促进了NiFeO颗粒更均匀的分布。鉴于亚甲基蓝（MB）降解反应符合一级动力学方程，NiFeO-CA纳米复合材料表现出优异的催化活性，在180分钟内几乎保持了99%的MB（60mg/L）去除率，并且在连续四个循环中保持了优异的稳定性。这项研究表明，NiFeO-CA纳米复合材料具有作为未来有效处理染料废水的潜力。
