Hezam Abdo, Namratha K, Ponnamma Deepalekshmi, Drmosh Q A, Saeed Adel Morshed Nagi, Sadasivuni Kishor Kumar, Byrappa Kullaiah
Center for Materials Science and Technology, University of Mysore, Vijnana Bhavan, Manasagangothiri, Mysuru 570006, India.
DOS in Earth Science, University of Mysore, Manasagangothiri, Mysuru 570006, India.
ACS Omega. 2019 Nov 25;4(24):20595-20605. doi: 10.1021/acsomega.9b02564. eCollection 2019 Dec 10.
Synthesis of metal oxide nanostructures through combustion routes is a promising technique owing to its simplicity, rapidity, scalability, and cost-effectiveness. Herein, a sunlight-driven combustion approach is developed to synthesize pristine metal oxides and their heterostructures. Sunlight, a sustainable energy source, is used not only to initiate the combustion reaction but also to create oxygen vacancies on the metal oxide surface. ZnO nanostructures are successfully synthesized using this novel approach, and the products exhibit higher photocatalytic activity in the decomposition of methyl orange (MO) than ZnO nanostructures synthesized by the conventional methods. The higher photocatalytic activity is due to the narrower band gap, higher porosity, smaller and more uniform particle size, surface oxygen vacancies, as well as the enhanced exciton dissociation efficiency induced by the sunlight. Porous FeO nanostructures are also prepared using this environmentally benign method. Surprisingly, few-layer BiO nanosheets are successfully obtained using the sunlight-driven combustion approach. Moreover, the approach developed here is used to synthesize BiO/ZnO heterostructure exhibiting a structure of few-layer BiO nanosheets decorated with ZnO nanoparticles. BiO nanosheets and BiO/ZnO heterostructures synthesized by sunlight-driven combustion route exhibit higher photocatalytic activity than their counterparts synthesized by the conventional solution combustion method. This work illuminates a potential cost-effective method to synthesize defective metal oxide nanostructures at scale.
通过燃烧法合成金属氧化物纳米结构是一种很有前景的技术，因为它具有简单、快速、可扩展和成本效益高的特点。在此，开发了一种阳光驱动的燃烧方法来合成原始金属氧化物及其异质结构。阳光作为一种可持续能源，不仅用于引发燃烧反应，还用于在金属氧化物表面产生氧空位。利用这种新方法成功合成了ZnO纳米结构，与传统方法合成的ZnO纳米结构相比，所得产物在甲基橙（MO）分解中表现出更高的光催化活性。较高的光催化活性归因于较窄的带隙、较高的孔隙率、更小且更均匀的粒径、表面氧空位以及阳光诱导的激子解离效率增强。还使用这种环境友好型方法制备了多孔FeO纳米结构。令人惊讶的是，利用阳光驱动的燃烧方法成功获得了几层BiO纳米片。此外，这里开发的方法用于合成具有由ZnO纳米颗粒装饰的几层BiO纳米片结构的BiO/ZnO异质结构。通过阳光驱动燃烧路线合成的BiO纳米片和BiO/ZnO异质结构比通过传统溶液燃烧法合成的同类产品表现出更高的光催化活性。这项工作阐明了一种潜在的经济高效方法，可大规模合成有缺陷的金属氧化物纳米结构。
