Abstract：
Industrial dye degradation involves several processes by which dyes are broken down, ideally into innocuous products. Methylene blue (MB) is one of the most commonly employed dyes in the textile industry and is released into water in routine industry processes. These discharges lead to creating a nocuous nature for humans and animals. Drugs are also discharged into water bodies from various pharmaceutical industries. In these two contexts, in the present work, the green synthesis of calcium-doped zinc oxide nanoparticles (Ca-doped ZnO NPs) is achieved using the aqueous peel extract of Citrus limetta by the solution combustion technique. The structural, morphological, and optical properties of the synthesized Ca-doped ZnO NPs are investigated using XRD, FTIR, SEM, EDX, and UV-visible spectroscopy. The prepared NPs were subjected to photocatalytic degradation of MB dye under visible-light illumination, which shows ~ 95% dye degradation. The synthesized Ca-doped ZnO NPs were also employed to adsorb tinidazole (TDZ), a nitroimidazole antibiotic, from water samples. An excellent adsorptive capacity of the NPs was observed for selectively adsorbing the TDZ ~ 96.2%. The drug TDZ was found to have pseudo-second-order kinetics. The catalyst recycling proved its repeatability; removal of the dye reached up to 92% after three successive usages. Therefore, using waste Citrus limetta peel extract, the multifunctional Ca-doped ZnO NPs were synthesized, which maintained effective adsorption potential and photocatalytic abilities and could be used as an effective material for environmental remediation.
摘要：
工业染料降解涉及染料分解的几个过程，理想情况下是无害的产品。亚甲基蓝(MB)是纺织工业中最常用的染料之一,并且在常规工业过程中释放到水中。这些放电导致人类和动物产生恶毒的性质。药物也从各种制药行业排放到水体中。在这两种情况下，在目前的工作中,通过溶液燃烧技术，使用柑橘的水性果皮提取物实现了钙掺杂氧化锌纳米颗粒（Ca掺杂ZnONPs）的绿色合成。结构,形态学,并利用XRD研究了合成的Ca掺杂ZnONPs的光学性质,FTIR,SEM,EDX,和紫外可见光谱。制备的NP在可见光照射下对MB染料进行光催化降解，显示~95%的染料降解。合成的Ca掺杂ZnONP也用于吸附替硝唑（TDZ），一种硝基咪唑抗生素,从水样。对于选择性吸附TDZ〜96.2%,观察到NPs的优异吸附能力。发现药物TDZ具有伪二级动力学。催化剂再循环证明了其可重复性；连续使用三次后，染料的去除率高达92％。因此,使用废柑橘皮提取物，合成了多功能Ca掺杂ZnONPs，保持有效的吸附潜力和光催化能力，可作为环境修复的有效材料。
