Multidisciplinary Nanotechnology Centre, College of Engineering, University of Swansea, Singleton Park, Swansea SA28PP, UK.
Nanoscale Res Lett. 2014 Jan 8;9(1):11. doi: 10.1186/1556-276X-9-11.
We have developed a low-cost technique using a conventional microwave oven to grow layered basic zinc acetate (LBZA) nanosheets (NSs) from a zinc acetate, zinc nitrate and HMTA solution in only 2 min. The as-grown crystals and their pyrolytic decomposition into ZnO nanocrystalline NSs are characterized by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), atomic force microscopy (AFM), X-ray diffraction (XRD) and photoluminescence (PL). SEM and AFM measurements show that the LBZA NSs have typical lateral dimensions of 1 to 5 μm and thickness of 20 to 100 nm. Annealing in air from 200°C to 1,000°C results in the formation of ZnO nanocrystalline NSs, with a nanocrystallite size ranging from 16 nm at 200°C to 104 nm at 1,000°C, as determined by SEM. SEM shows evidence of sintering at 600°C. PL shows that the shape of the visible band is greatly affected by the annealing temperature and that the exciton band to defect band intensity ratio is maximum at 400°C and decreases by a factor of 15 after annealing at 600°C. The shape and thickness of the ZnO nanocrystalline NSs are the same as LBZA NSs. This structure provides a high surface-to-volume ratio of interconnected nanoparticles that is favorable for applications requiring high specific area and low resistivity such as gas sensing and dye-sensitized solar cells (DSCs). We show that resistive gas sensors fabricated with the ZnO NSs showed a response of 1.12 and 1.65 to 12.5 ppm and 200 ppm of CO at 350°C in dry air, respectively, and that DSCs also fabricated from the material had an overall efficiency of 1.3%. PACS: 81.07.-b; 62.23.Kn; 61.82.Fk.
我们开发了一种使用常规微波炉的低成本技术，仅用 2 分钟即可从乙酸锌、硝酸锌和 HMTA 溶液中生长出层状基本乙酸锌（LBZA）纳米片（NS）。用扫描电子显微镜（SEM）、能谱（EDS）、原子力显微镜（AFM）、X 射线衍射（XRD）和光致发光（PL）对生长的晶体及其热解分解为 ZnO 纳米晶 NS 进行了表征。SEM 和 AFM 测量表明，LBZA NS 具有典型的横向尺寸为 1 到 5 μm，厚度为 20 到 100 nm。在空气中从 200°C 到 1000°C 退火导致形成 ZnO 纳米晶 NS，纳米晶尺寸从 200°C 的 16 nm 到 1000°C 的 104 nm，由 SEM 确定。SEM 显示 600°C 时出现烧结现象。PL 表明，可见光带的形状受退火温度的影响很大，激子带与缺陷带强度比在 400°C 时最大，在 600°C 退火后下降了 15 倍。ZnO 纳米晶 NS 的形状和厚度与 LBZA NS 相同。这种结构提供了具有高比表面积和低电阻率的互连纳米颗粒的高表面积-体积比，有利于需要高比表面积和低电阻率的应用，如气体传感和染料敏化太阳能电池（DSC）。我们表明，用 ZnO NS 制造的电阻式气体传感器在 350°C 下对 12.5 ppm 和 200 ppm 的 CO 在干燥空气中分别表现出 1.12 和 1.65 的响应，并且由该材料制造的 DSCs 的总效率为 1.3%。PACS：81.07.-b；62.23.Kn；61.82.Fk。
