采用热蒸发气相沉积法在Si(100)衬底上生长直径约为60~70nm的氧化锌(ZnO)纳米线,进一步运用离子束溅射技术和热氧化工艺在ZnO纳米线表面形成含有均匀密集分布的超细氧化铜(CuO)纳米颗粒的CuO壳层,构成n-ZnO(核芯)/p-CuO(壳层)同轴纳米线异质结.扫描电子显微镜(SEM)、X射线衍射(XRD)、透射电子显微镜(TEM)和高分辨透射电子显微镜(HRTEM)用于研究样品的形貌、成分和晶体结构.实验结果表明,生长的ZnO纳米线呈纤锌矿单晶结构,CuO壳层为多晶结构.Ⅰ-Ⅴ曲线表明该同轴纳米线异质结构具有优良的二极管整流特性.这种具有大的异质结面积和高的比表面受光面积及强的表面化学活性的n-ZnO/p-CuO同轴纳米线异质结构在大电流密度的纳米整流器件、太阳能电池、光敏器件和气敏传感器等领域有很好的应用前景.
n-ZnO/p CuO coaxial nanocable heterojunctions were fabricated by a two-step method. The ZnO nanowires were first synthesized on silicon(100) substrates via a thermal vapor deposition route. Then the CuO shells with uniform, intensive and ultrafine CuO nanoparticles were prepared on the surfaces of ZnO nanowires using the ion beam sputtering technology combining thermal oxidation process. Scanning electron microscopy (SEM), X-ray dif fraction (XRD), transmission electron microscopy(TEM)and high-resolution transmission electron microscopy (HR- TEM) were used to study the morphology, composition and crystal structure of ZnO/CuO samples. The results indi- cate that the grown ZnO nanowires have Wurtzite single-crystalline structure and the CuO nanoshells display polycrys talline structure. The current-voltage (I-V) measurement based on the n-ZnO/p-CuO hetrojunetions showed an excel lent typical semiconductor rectification characteristic. The n-ZnO/p-CuO coaxial nanocable heterojunctions, with large heterojunction area, large light illumination surface area and strong surface chemical activity, have promising applications in the fields of nano-rectifiers with high current density, solar cells, photosensitive devices and gas sen sors