Luque Morales Mizael, Luque Morales Priscy Alfredo, Chinchillas Chinchillas Manuel de Jesús, Orozco Carmona Víctor Manuel, Gómez Gutiérrez Claudia Mariana, Vilchis Nestor Alfredo Rafael, Villarreal Sánchez Rubén César
Facultad de Ingeniería Arquitectura y Diseño, Universidad Autónoma de Baja California, Ensenada 22860, Mexico.
Departamento de Ingeniería y Tecnología, Universidad Autónoma de Occidente, Guasave 81048, Mexico.
Materials (Basel). 2023 Sep 12;16(18):6169. doi: 10.3390/ma16186169.
In this work, the photocatalytic activity of nanoparticles (NPs) of zinc oxide synthetized by as a stabilizing agent was evaluated in the degradation of methylene blue (MB) dye under UV radiation. The theoretical study of the photocatalytic degradation process was carried out by a Langmuir-Hinshelwood-Hougen-Watson (LHHW) model. Zinc oxide nanoparticles were synthesized by varying the concentration of natural extract of Prosopis laevigata from 1, 2, and 4% (weight/volume), identifying the samples as ZnO_PL1%, ZnO_PL2%, and ZnO_PL4%, respectively. The characterization of the nanoparticles was carried out by Fourier transform infrared spectroscopy (FT-IR), where the absorption band for the Zn-O vibration at 400 cm was presented; by ultraviolet-visible spectroscopy (UV-vis) the value of the band gap was calculated, resulting in 2.80, 2.74 and 2.63 eV for the samples ZnO_PL1%, ZnO_PL2%, and ZnO_PL4%, respectively; XRD analysis indicated that the nanoparticles have a hexagonal zincite crystal structure with an average crystal size of 55, 50, and 49 in the sample ZnO_PL1%, ZnO_PL2%, and ZnO_PL4%, respectively. The morphology observed by TEM showed that the nanoparticles had a hemispherical shape, and the ZnO_PL4% sample presented sizes ranging between 29 and 45 nm. The photocatalytic study showed a total degradation of the MB in 150, 120, and 60 min for the samples ZnO_PL1%, ZnO_PL2%, and ZnO_PL4%, respectively. Also, the model explains the experimental observation of the first-order kinetic model in the limit of low concentrations of dye, indicating the influence of the mass transfer processes.
在本研究中，评估了以 作为稳定剂合成的氧化锌纳米颗粒（NPs）在紫外辐射下对亚甲基蓝（MB）染料降解的光催化活性。通过Langmuir-Hinshelwood-Hougen-Watson（LHHW）模型对光催化降解过程进行了理论研究。通过改变光滑牧豆树天然提取物的浓度（1%、2%和4%（重量/体积））合成氧化锌纳米颗粒，分别将样品鉴定为ZnO_PL1%、ZnO_PL2%和ZnO_PL4%。通过傅里叶变换红外光谱（FT-IR）对纳米颗粒进行表征，其中在400 cm处出现了Zn-O振动的吸收带；通过紫外-可见光谱（UV-vis）计算带隙值，样品ZnO_PL1%、ZnO_PL2%和ZnO_PL4%的带隙值分别为2.80、2.74和2.63 eV；XRD分析表明，纳米颗粒具有六方纤锌矿晶体结构，样品ZnO_PL1%、ZnO_PL2%和ZnO_PL4%的平均晶体尺寸分别为55、50和49 。通过TEM观察到的形态表明，纳米颗粒呈半球形，ZnO_PL4%样品的尺寸范围在29至45 nm之间。光催化研究表明，样品ZnO_PL1%、ZnO_PL2%和ZnO_PL4%分别在150、120和60分钟内实现了MB的完全降解。此外，该模型解释了在低染料浓度极限下一级动力学模型的实验观察结果，表明了传质过程的影响。
