Environmental Research Lab, Department of Chemistry, Chandigarh University, Mohali, Punjab 140413, India.
School of Materials Science and Engineering, Changwon National University, Changwon 51140, Gyeongnam, South Korea.
Int J Biol Macromol. 2023 Jul 31;244:125221. doi: 10.1016/j.ijbiomac.2023.125221. Epub 2023 Jun 8.
The present study involves the synthesis of green functional material based on the silver nanoparticle (Ag NPs) doped cellulose nanocrystals (CNC) immobilized agar gum (AA) biopolymer using chemical coprecipitation method. The stabilization of Ag NPs in cellulose matrix and functionalization of the synthesized material through agar gum was analyzed using various spectroscopic techniques such as Fourier Transform Infrared (FTIR), Scanning electron microscope (SEM), Energy X-Ray diffraction (EDX), Photoelectron X-ray (XPS), Transmission electron microscope (TEM), Selected area energy diffraction (SAED) and ultraviolet visible (UV-Vis) spectroscopy. The XRD results suggested that the synthesized AA-CNC@Ag BNC material is composed of 47 % crystalline and 53 % amorphous nature having distorted hexagonal structure due to capping of Ag NPs by amorphous biopolymer matrix. The Debye-Scherer crystallite sized was calculated as 18 nm which is found in close agreement with TEM analysis (19 nm). The SAED yellow fringes simulates the miller indices values with XRD patterns and supported the surface functionalization of Ag NPs by biopolymer blend of AA-CNC. The XPS data supported the presence of Ag as indexed by Ag3d orbital corresponding to Ag3d at 372.6 eV and Ag3d at 366.6 eV. The surface morphological results revealed a flaky surface of the resultant material having well distributed Ag NPs in the matrix. The EDX and atomic concentration results given by XPS supported the presence if C, O and Ag in the bionanocomposite material. The UV-Vis results suggested that the material is both UV and visible light active having multiple SPR effects with anisotropy. The material was explored as a photocatalyst for remediation of wastewater contaminated by malachite green (MG) using advance oxidation process (AOP). Photocatalytic experiments were performed in order to optimize various reaction parameters such as irradiation time, pH, catalyst dose and MG concentration. The obtained results showed that almost 98.85 % of MG was degraded by using 20 mg of catalyst at pH 9 for 60 min of irradiation. The trapping experiments revealed that O radicals played primary role in MG degradation. This study will provide new possible strategies for the remediation of wastewater contaminated by MG.
本研究涉及通过化学共沉淀法合成基于银纳米粒子（Ag NPs）掺杂纤维素纳米晶体（CNC）固定琼脂糖（AA）生物聚合物的绿色功能材料。使用各种光谱技术，如傅里叶变换红外（FTIR）、扫描电子显微镜（SEM）、能量 X 射线衍射（EDX）、光电 X 射线（XPS）、透射电子显微镜（TEM）、选区电子衍射（SAED）和紫外可见（UV-Vis）光谱分析，对 Ag NPs 在纤维素基质中的稳定性和合成材料的功能化进行了分析。XRD 结果表明，合成的 AA-CNC@Ag BNC 材料由 47%的结晶相和 53%的非晶相组成，由于非晶生物聚合物基质对 Ag NPs 的包覆，其具有扭曲的六方结构。通过谢乐公式计算得到的德拜-谢乐晶粒尺寸为 18nm，与 TEM 分析结果（19nm）非常吻合。SAED 黄色条纹模拟了与 XRD 图谱相符的米勒指数值，并支持 Ag NPs 通过 AA-CNC 生物聚合物混合物的表面功能化。XPS 数据支持 Ag 的存在，Ag 索引为 Ag3d 轨道，对应于 Ag3d 在 372.6 eV 和 Ag3d 在 366.6 eV。表面形貌结果表明，所得材料具有片状表面，基质中 Ag NPs 分布均匀。EDX 和 XPS 给出的原子浓度结果支持 bionanocomposite 材料中存在 C、O 和 Ag。UV-Vis 结果表明，该材料具有紫外和可见光活性，具有多重各向异性的 SPR 效应。该材料被探索作为一种光催化剂，用于使用高级氧化工艺（AOP）修复受孔雀石绿（MG）污染的废水。进行了光催化实验，以优化各种反应参数，如辐照时间、pH 值、催化剂剂量和 MG 浓度。得到的结果表明，在 pH 为 9、辐照 60 分钟的条件下，使用 20mg 催化剂，MG 几乎降解了 98.85%。捕获实验表明，O 自由基在 MG 降解中起主要作用。这项研究将为受 MG 污染的废水的修复提供新的可能策略。
