Akhtar Muhammad Shahbaz, Jutt Deborah Sohrab Rustam, Aslam Sohaib, Nawaz Rab, Irshad Muhammad Atif, Khan Maheer, Khairy M, Irfan Ali, Al-Hussain Sami A, Zaki Magdi E A
Department of Environmental Sciences, Forman Christian College University, Lahore, 54600, Pakistan.
Department of Environmental Sciences, The University of Lahore, Lahore, 54000, Pakistan.
Sci Rep. 2024 Oct 4;14(1):23094. doi: 10.1038/s41598-024-73734-9.
Graphene-based nanomaterials have been proved to be robust sorbents for efficient removal of environmental contaminants including arsenic (As). Biobased graphene oxide (bGO-P) derived from sugarcane bagasse via pyrolysis, GO-C via chemical exfoliation, and magnetite nanoparticles (FeNPs) via green approach using Azadirachta indica leaf extract were synthesized and characterized by Ultraviolet-Visible Spectrophotometer (UV-vis.), Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), mean particle size and Scanning electron microscopy (SEM) along with Energy dispersive spectroscopy (EDX) analysis. Compared to cellulose and hemicellulose, the lignin fraction was less in the precursor material. The GOC, bGO-P and FeNPs displayed maximum absorption at 230, 236, and 374 nm, respectively. FTIR spectrum showed different functional groups (C-OH, C-O-C, COOH and O-H) modifying the surfaces of synthesized materials. Graphene based nanomaterials showed clustered dense flakes of GO-C and thin transparent flakes of bGO-P. Elemental composition by EDX analysis of GO-C (71.26% C and 27.36% O), bGO-P (74.54% C and 24.61% O) and FeNPs (55.61% Fe, 4.1% C and 35.72% O) confirmed the presence of carbon, oxygen, and iron in synthesized nanomaterials. Sorption study was conducted with soil amended with different doses of synthesized nanomaterials (10, 50 and 250 mg) and exposed to 100, 300 and 500 ppm of As. Arsenic concentrations were estimated by colorimetry and atomic absorption spectroscopy (AAS). GO-C, bGO-P, and FeNPs showed substantial As removal efficiency i.e., 81 to 99.3%, 65 to 98.8% and 73.1-89.9%, respectively. Green synthesis of bGO-P and magnetite nanoparticles removed substantial amounts of As compared to GO-C and can be effectively deployed for As removal or immobilization. Higher and medium sorbent doses (250 and 50 mg) exhibited greater As removal and data was best fitted for Freundlich isotherm evidencing favorable sorption. Nevertheless, at low sorbent doses, data was best fitted for both models. Newly synthesized nanomaterials emerged as promising materials for As removal strategy for soil nano-remediation and can be effectively deployed in As contaminated soils.
基于石墨烯的纳米材料已被证明是用于有效去除包括砷（As）在内的环境污染物的强大吸附剂。通过热解从甘蔗渣中衍生出的生物基氧化石墨烯（bGO-P）、通过化学剥离得到的GO-C以及使用印楝叶提取物通过绿色方法制备的磁铁矿纳米颗粒（FeNPs）被合成，并通过紫外可见分光光度计（UV-vis.）、傅里叶变换红外（FTIR）光谱、X射线衍射（XRD）、平均粒径以及扫描电子显微镜（SEM）和能量色散光谱（EDX）分析进行了表征。与纤维素和半纤维素相比，前体材料中的木质素含量较少。GOC、bGO-P和FeNPs分别在230、236和374nm处显示出最大吸收。FTIR光谱显示不同的官能团（C-OH、C-O-C、COOH和O-H）修饰了合成材料的表面。基于石墨烯的纳米材料显示出GO-C的聚集致密薄片和bGO-P的薄透明薄片。通过EDX分析得到的GO-C（71.26% C和27.36% O）、bGO-P（74.54% C和24.61% O）和FeNPs（55.61% Fe、4.1% C和35.72% O）的元素组成证实了合成纳米材料中存在碳、氧和铁。用不同剂量（10、50和250mg）的合成纳米材料改良土壤并使其暴露于100、300和500ppm的As下进行吸附研究。通过比色法和原子吸收光谱法（AAS）估算砷浓度。GO-C、bGO-P和FeNPs分别显示出较高的As去除效率，即81%至99.3%、65%至98.8%和73.1 - 89.9%。与GO-C相比，bGO-P和磁铁矿纳米颗粒的绿色合成去除了大量的As，并且可以有效地用于As的去除或固定。较高和中等吸附剂剂量（250和50mg）表现出更高的As去除率，数据最符合弗伦德里希等温线，表明吸附良好。然而，在低吸附剂剂量下，数据对两种模型都最拟合。新合成的纳米材料成为用于土壤纳米修复中As去除策略的有前景的材料，并且可以有效地应用于受As污染的土壤中。
