研究目的
To investigate the influence of exposure time on the morphology, microstructure, optical, and photoluminescence properties of ZnO micro- and nanostructures produced by thermal oxidation of Zn powders, and to propose growth mechanisms and experimental parameters for fabricating specific structures.
研究成果
Thermal oxidation of Zn powders at 900°C in air produces various ZnO micro- and nanostructures (rounded, elongated, hollow, tetrapods) depending on exposure time. Growth mechanisms include solid-solid, liquid-solid, and vapor-solid processes. Extending exposure time increases point defects, enhancing visible luminescence. Proposed methods for controlled morphology involve specific temperatures, atmospheres, and particle-size distributions.
研究不足
The study is limited to air atmosphere and fixed temperature (900°C); variations in atmosphere composition or temperature were not explored. The use of Zn powder with broad particle-size distribution may lead to simultaneous growth of different morphologies, making it challenging to isolate specific structures. The non-stoichiometry of ZnO samples and point defects could affect properties, and further optimization is needed for controlled morphology synthesis.
1：Experimental Design and Method Selection:
Thermal oxidation of Zn powders at 900°C in air atmosphere for varying exposure times (3, 6, 12, 24 minutes) to study the evolution of ZnO structures.
2：Sample Selection and Data Sources:
Zn powder precursor (>99% purity, Meyer brand) was used; samples labeled S0 (precursor), S1 (3 min), S2 (6 min), S3 (12 min), S4 (24 min).
3：List of Experimental Equipment and Materials:
Alumina crucible, open-end quartz tube, horizontal furnace, Zn powder. Characterization equipment: X-ray diffractometer (Advance D-8, Bruker), micro-Raman spectrometer (LabRAM HR-Olympus, Horiba Jobin Yvon), field-emission scanning electron microscope (MIRA3-LM FE-SEM, TESCAN), energy dispersive X-ray spectrometer (QUANTAX XFlash 6|30, Bruker), diffuse reflectance spectrophotometer (Cary 5000, Agilent), spectrofluorometer (NanoLog, Horiba Jobin Yvon).
4：6|30, Bruker), diffuse reflectance spectrophotometer (Cary 5000, Agilent), spectrofluorometer (NanoLog, Horiba Jobin Yvon). Experimental Procedures and Operational Workflow:
4. Experimental Procedures and Operational Workflow: Place
5：5g Zn powder in alumina crucible, quickly introduce into preheated furnace at 900°C, maintain for specific time, then extract and cool freely. Characterize using XRD, Raman, SEM, EDS, DRS, PL/PLE techniques. Data Analysis Methods:
XRD for phase identification and strain analysis, Raman for defect analysis, SEM for morphology, EDS for elemental composition, DRS for band gap determination using Kubelka-Munk formalism, PL/PLE for emission properties.
独家科研数据包，助您复现前沿成果，加速创新突破
获取完整内容
