摘要
电荷在电极材料内部的传输对光电转换器件的性能起着着重要的决定因素。传统的由纳米颗粒无序堆积的薄膜电极通常呈现出低的电荷传输速率。为了解决这一问题,我们做了以下工作:(1)我们合成了单晶阵列一维TiO_2纳米线结构,并首次证明了其电荷传输性能比纳米颗粒无序堆积的薄膜高200多倍;(2)虽然阵列一维TiO_2纳米线结构有良好的电荷传输性能,但纳米线之间的空隙降低了其比表面积。我们在一维TiO_2纳米线基础上外延组装了分支结构。这一结构在维持了电荷传输性能的基础上,比表面积相比一维纳米线结构提高了71%;(3)我们进而合成了具有特殊的[10-10]取向的多通道阵列ZnO结构。与纳米颗粒ZnO堆积的薄膜相比,这种结构具有可比拟的比表面积,并且电荷传输性能提高了2-3个数量级。这些同时具有高的比表面以及快速电荷传输性能的新型电极结构将在未来的光电转换器件中发挥重要作用。
Charge transport within electrode materials is a major determinant of optoelectronic device performances. Conventional electrode with randomly packed nanoparticles always exhibits significantly low electron mobility. To address these challenges,(1) We fabricated single-crystal 1D TiO_2 nanowire(NW) arrays and first demonstrated that their electron transport is 200-fold higher than that in NP films.(2) To enlarge the surface area of 1D NWs sturctures, we fabricated oriented assembled TiO_2 hierarchical nanoarrays consisting of 1D branches epitaxially grown from the primary trunks. It shows 71% higher surface area related to 1D NW arrays without affecting electron transport.(3) We reported [10-10] oriented ZnO NW arrays with multichannel structure, which exhibits 2-3 orders of magnitude faster electron transport rate than that in NP films as well as comparable surface area. These novel nanoarry materials with high surface area and rapid charge transport properties make them ideal electrodes for future various optoelectronic device applications.
引文
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