Aaga Gemechu Fikadu, Anshebo Sisay Tadesse
College of Natural and Computational Sciences, Department of Chemistry, Dilla University, Dilla Ethiopia.
College of Natural and Computational Sciences, Department of Chemistry, Hawassa University, Hawassa Ethiopia.
Heliyon. 2023 May 6;9(5):e16067. doi: 10.1016/j.heliyon.2023.e16067. eCollection 2023 May.
Environmental pollution by organic pollutants because of population growth and industrial expansion is a global concern. Following this, the fabrication of single and efficient nanomaterials for pollution control is highly demanded. Under this study, highly efficient and stable copper oxide nanoparticles (CuO NPs) were synthesized through the green method using Moringa stenopetala seed extract. XRD, UV-vis, FT-IR, and SEM were applied to characterize the synthesized material. From XRD data, the average particle size was found to be 6.556 nm, and the nanoparticles are crystalline in nature. The formation of CuO NPs was demonstrated by FT-IR spectra of Cu-O in different bending vibration bands at 535 cm-1 and 1122 cm-1, as well as stretching vibration of Cu-O at 1640 cm-1. From UV-visible spectroscopic measurements, the energy band gap of greenly synthesized CuO NPs was found to be 1.73 eV. The SEM result shows that the nanoparticles' surfaces are rough, with some of the particles having spherically random orientation. The photodegradation efficiency of green synthesized CuO NPs photocatalyst was found to be 98.35% for Congo red at optimum experimental parameters (initial concentration, 25 mg/L; exposure time, 120 min; catalyst dose, 0.2 g; and pH, 5) and 95.4% for Alizarin Red S at optimum experimental parameters (catalyst dose, 0.25 g; initial concentration, 40 mg/L; exposure time, 120 min; and pH, 4.6). The COD values determined for the degraded product strongly support the complete mineralization of the dyes toward nontoxic materials. Reusability of the catalyst was investigated for five cycles, and the results clearly indicate the green synthesized CuO NPs are highly stable, can be used for several times, and are cost-effective as well. The degradation of Congo red and Alizarin red S on the surface of the CuO NPs follows the MBG kinetic model.
由于人口增长和工业扩张导致的有机污染物环境污染是一个全球关注的问题。在此背景下，人们迫切需要制备单一且高效的用于污染控制的纳米材料。在本研究中，使用辣木种子提取物通过绿色方法合成了高效且稳定的氧化铜纳米颗粒（CuO NPs）。采用X射线衍射（XRD）、紫外可见光谱（UV-vis）、傅里叶变换红外光谱（FT-IR）和扫描电子显微镜（SEM）对合成材料进行表征。根据XRD数据，发现平均粒径为6.556纳米，且纳米颗粒为晶体性质。在535厘米-1和1122厘米-1处不同弯曲振动带的Cu-O的FT-IR光谱以及在1640厘米-1处Cu-O的拉伸振动证明了CuO NPs的形成。通过紫外可见光谱测量，发现绿色合成的CuO NPs的能带隙为1.73电子伏特。SEM结果表明，纳米颗粒表面粗糙，一些颗粒具有球形随机取向。在最佳实验参数（初始浓度25毫克/升；暴露时间120分钟；催化剂剂量0.2克；pH值5）下，绿色合成的CuO NPs光催化剂对刚果红的光降解效率为98.35%，在最佳实验参数（催化剂剂量0.25克；初始浓度40毫克/升；暴露时间120分钟；pH值4.6）下对茜素红S的光降解效率为95.4%。对降解产物测定的化学需氧量（COD）值有力地支持了染料完全矿化为无毒物质。对催化剂的可重复使用性进行了五个循环的研究，结果清楚地表明绿色合成的CuO NPs高度稳定，可以多次使用，且具有成本效益。CuO NPs表面上刚果红和茜素红S的降解遵循MBG动力学模型。
