Suresh D, Nethravathi P C, Lingaraju K, Rajanaika H, Sharma S C, Nagabhushana H
Department of Studies and Research in Chemistry, Tumkur University, Tumkur, Karnataka 572 103, India.
Department of Studies and Research in Chemistry, Tumkur University, Tumkur, Karnataka 572 103, India.
Spectrochim Acta A Mol Biomol Spectrosc. 2015 Feb 5;136 Pt C:1467-74. doi: 10.1016/j.saa.2014.10.038. Epub 2014 Nov 4.
Zinc oxide nanopowders were synthesized by solution combustion method using Epigallocatechin gallate (EGCG) a tea catechin as fuel. The structure and morphology of the product was characterized by Powder X-ray Diffraction, Scanning Electron Microscopy, photoluminescence and UV-Visible spectroscopy. The nanopowders (Nps) were subjected to photocatalytic and biological activities such as antimicrobial and antioxidant studies. PXRD patterns demonstrate that the formed product belongs to hexagonal wurtzite system. SEM images show that the particles are agglomerated to form sponge like structure and the average crystallite sizes were found to be ∼10-20nm. PL spectra exhibit broad and strong peak at 590nm due to the Zn-vacancies, and O-vacancies. The prepared ZnO Nps exhibit excellent photocatalytic activity for the photodegradation of malachite green (MG) and methylene blue (MB) indicating that the ZnO NPs are potential photocatalytic semiconductor materials. ZnO NPs exhibit significant bactericidal activity against Klebsiella aerogenes, Pseudomonas aeruginosa, Escherichia coli and Staphylococcus aureus using the agar well diffusion method. Furthermore, the ZnO nano powders show good antioxidant activity by potentially scavenging DPPH radicals. The study successfully demonstrates synthesis of ZnO NPs by simple ecofriendly route employing EGCG as fuel that exhibit superior photodegradative, antibacterial and antioxidant activities.
采用表没食子儿茶素没食子酸酯（EGCG，一种茶叶儿茶素）作为燃料，通过溶液燃烧法合成了氧化锌纳米粉末。采用粉末X射线衍射、扫描电子显微镜、光致发光和紫外可见光谱对产物的结构和形貌进行了表征。对纳米粉末（Nps）进行了光催化和生物活性研究，如抗菌和抗氧化研究。粉末X射线衍射图谱表明，所形成的产物属于六方纤锌矿体系。扫描电子显微镜图像显示，颗粒团聚形成海绵状结构，平均晶粒尺寸约为10-20nm。由于锌空位和氧空位，光致发光光谱在590nm处呈现出宽而强的峰。制备的氧化锌纳米颗粒对孔雀石绿（MG）和亚甲基蓝（MB）具有优异的光催化降解活性，表明氧化锌纳米颗粒是潜在的光催化半导体材料。采用琼脂扩散法，氧化锌纳米颗粒对产气克雷伯菌、铜绿假单胞菌、大肠杆菌和金黄色葡萄球菌具有显著的杀菌活性。此外，氧化锌纳米粉末通过潜在地清除DPPH自由基显示出良好的抗氧化活性。该研究成功地证明了通过简单的环保路线，以EGCG为燃料合成氧化锌纳米颗粒，其具有优异的光降解、抗菌和抗氧化活性。
