Greenleaf extracts have been used as reducing agents for the synthesis of various nanoparticles because of their high antioxidant capacity and environmentally benign reducing properties. Five different plant species were chosen for this comparative study of the synthesis of iron oxide nanoparticles for arsenic adsorption. Based on the excellent reducing properties reported in previous studies, the following plant leaves were selected: black tea leaves (Camellia sinensis), oak tree leaves (Quercus virginiana), green tea leaves (C. sinensis), pomegranate leaves (Punica granatum), and eucalyptus leaves (Eucalyptus globulus). Iron nanoparticles were synthesized using the green synthesis method with the above leaves. The adsorption capacity of the nanoparticles was determined by carrying out kinetic and adsorption isotherm studies. Eucalyptus leaf nanoparticles were determined to be having the highest arsenic adsorption capacity of 39.84 mg/g, followed by oaktree leaf nanoparticles of adsorption capacity 32.05 mg/g. This indicates that locally available and nonagricultural trees are better suited for green synthesis of iron nanoparticle for arsenic remediation compared to green tea, or back tea leaves. The experiments revealed that the adsorption kinetics followed the pseudo-second-order rate equation and that the Langmuir equation could best describe adsorption isotherm data. The nanoparticles were characterized using SEM coupled with EDS, XRD, BET surface area, and UV Spectroscopy. The SEM images indicated that the iron oxide nanoparticles had spherical morphology with particle diameter around 10–100 nm and were amorphous in structure. The elemental analysis done by Energy dispersive spectroscopy (EDS) showed their weight percentage of C, O, Fe, S to be 44.70%, 32.80%, 20.56%, and 0.65%, respectively.

1. Highlights

2. Iron nanoparticles were synthesized by five different leaf extracts of locally available plants with high reported antioxidant capacity.

3. The five green-synthesized nanoparticles were characterized using EDS, XRD, FTIR, BET, and UV spectrometry.

4. The adsorption behavior of the five nanoparticles was studied using kinetic and adsorption isotherm experiments.

5. The best adsorbing nanoparticles were determined to be from oakleaf and eucalyptus leaf extracts, which are nonagricultural tree leaves, and can be obtained easily.

6. The oak leaves of Quercus virginiana species were used for the first time for the synthesis of iron oxide nanoparticles and they showed promising results in the form of high adsorption capacity for the removal of As (V).

绿叶提取物由于其高抗氧化能力和对环境有益的还原性能，已被用作合成各种纳米颗粒的还原剂。选择了五种不同的植物物种进行该比较研究，以合成用于砷吸附的氧化铁纳米颗粒。基于先前研究报告的优异还原性，选择了以下植物叶片：黑茶叶（山茶），橡树叶（栎属栎），绿茶叶（C. sinensis），石榴叶（石榴），和桉树叶（桉树球）。使用绿色合成方法，用上述叶子合成了铁纳米颗粒。通过进行动力学和吸附等温线研究来确定纳米颗粒的吸附能力。桉树叶纳米颗粒的砷吸附量最高，为39.84 mg / g，其次是橡树叶纳米颗粒，吸附量为32.05 mg / g。这表明，与绿茶或回茶相比，本地可利用的非农业树木更适合于绿色合成的铁纳米粒子用于砷的修复。实验表明，吸附动力学遵循伪二级速率方程，Langmuir方程最能描述吸附等温线数据。使用SEM与EDS，XRD，BET表面积，和紫外光谱。SEM图像表明，氧化铁纳米颗粒具有球形形态，粒径在10–100 nm左右，并且在结构上是无定形的。通过能量色散谱仪（EDS）进行的元素分析显示，它们的C，O，Fe，S的重量百分比分别为44.70％，32.80％，20.56％和0.65％。

1. 强调

2. 铁纳米颗粒由当地植物的五种不同叶提取物合成，具有较高的抗氧化能力。

3. 使用EDS，XRD，FTIR，BET和UV光谱对五个绿色合成的纳米颗粒进行了表征。

4. 使用动力学和吸附等温线实验研究了五个纳米颗粒的吸附行为。

5. 确定的最佳吸附纳米颗粒来自橡树叶和桉树叶提取物，它们是非农业树叶，很容易获得。

6. 栎栎种的橡树叶子首次用于氧化铁纳米颗粒的合成，并以高吸附能力去除As（V）形式显示出令人鼓舞的结果。