Department of Materials Science and Engineering, National Chiao Tung University, No. 1001, University Rd, East Dist, Hsinchu City, 300, Taiwan.
Nanoscale. 2012 Mar 7;4(5):1471-5. doi: 10.1039/c1nr10796h. Epub 2011 Oct 7.
Well-aligned ZnO nanowires (NWs) were successfully synthesized on Si(100) by the process of carbothermal reduction and vapor-liquid-solid method. Scanning electron microscopy and transmission electron microscopy results confirmed that ZnO NWs were single crystalline wurtzite structures and grew along the [0001] direction. The influences of substrate temperature and total pressure on the growth were discussed. The well-aligned ZnO NWs show good field emission properties, and the emitter constructed of pencil-like ZnO NWs exhibited a low turn-on field (3.82 V μm(-1)) and a high field enhancement factor (β = 2303). Finally, we demonstrated that the as-prepared ZnO NWs with small diameter on the substrate have good photocatalytic activity toward degradation of methylene blue. Using ZnO NWs with Au nanoparticles (NPs) would decrease the recombination rate of hole-electron pairs due to the great shift of the Fermi level to the conduction band. Hence, adding Au NPs was a promising method to enhance the photocatalytic performance of ZnO NWs. It is significant that photocatalyst fabricated by ZnO NWs can apply to the degradation of organic pollution, and solve the environmental issues.
通过碳热还原和汽液固法，成功地在 Si(100)衬底上合成了取向一致的 ZnO 纳米线（NWs）。扫描电子显微镜和透射电子显微镜的结果证实，ZnO NWs 具有单晶纤锌矿结构，沿[0001]方向生长。讨论了衬底温度和总压对生长的影响。取向一致的 ZnO NWs 表现出良好的场发射性能，由铅笔状 ZnO NWs 构成的发射器具有低开启场（3.82 V μm(-1)) 和高场增强因子（β = 2303）。最后，我们证明了在衬底上具有小直径的所制备的 ZnO NWs 对亚甲基蓝的降解具有良好的光催化活性。由于费米能级向导带的极大位移，Au 纳米颗粒（NPs）的添加会降低空穴-电子对的复合速率。因此，添加 Au NPs 是增强 ZnO NWs 光催化性能的一种很有前途的方法。重要的是，由 ZnO NWs 制成的光催化剂可应用于有机污染物的降解，从而解决环境问题。
