Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education of the People's Republic of China, Heilongjiang University, Harbin 150080, PR China.
Nanoscale. 2016 Apr 28;8(17):9366-75. doi: 10.1039/c6nr01969b.
In this study, a ZnO/ZnSe nanonail array was prepared via a two-step sequential hydrothermal synthetic route. In this synthetic process, the ZnO nanorod array was first grown on a fluorine-doped tin oxide (FTO) substrate using a seed-mediated growth approach via the hydrothermal process. Then, the ZnO nanonail array was obtained via in situ growth of ZnSe nano caps onto the ZnO nanorod array via a hydrothermal process in the presence of a Se source. The surface morphology and amount of ZnSe grown on the surface of the ZnO nanorods can be regulated by varying the reaction time and reactant concentration. Compared with pure ZnO nanorods, this unique nanonail array heterostructure exhibits enhanced visible light absorption. The transient photocurrent condition, in combination with steady-state and time-resolved photoluminescence spectroscopy, reveals that the ZnO/ZnSe nanonail array electrode has the highest charge separation rate, highest electron injection efficiency, and highest chemical stability. The photocurrent density of the ZnO/ZnSe nanonail array heterostructure reaches 1.01 mA cm(-2) at an applied potential of 0.1 V (vs. Ag/AgCl), which is much higher than that of the ZnO/ZnSe nanorod array (0.71 mA cm(-2)), the pristine ZnO nanorod array (0.39 mA cm(-2)), and the ZnSe electrode (0.21 mA cm(-2)), indicating its significant visible light driven activities for photoelectrochemical water oxidation. This unique morphology of nail-capped nanorods might be important for providing better insight into the correlation between heterostructure and photoelectrochemical activity.
在这项研究中，通过两步顺序水热合成路线制备了 ZnO/ZnSe 纳米钉阵列。在这个合成过程中，首先通过水热法使用种子介导生长方法在掺氟氧化锡（FTO）衬底上生长 ZnO 纳米棒阵列。然后，通过在存在硒源的水热过程中，将 ZnSe 纳米帽原位生长到 ZnO 纳米棒阵列上，得到 ZnO 纳米钉阵列。通过改变反应时间和反应物浓度，可以调节生长在 ZnO 纳米棒表面上的 ZnSe 的量和表面形貌。与纯 ZnO 纳米棒相比，这种独特的纳米钉阵列异质结构表现出增强的可见光吸收。瞬态光电流条件，结合稳态和时间分辨光致发光光谱，表明 ZnO/ZnSe 纳米钉阵列电极具有最高的电荷分离速率、最高的电子注入效率和最高的化学稳定性。在 0.1 V（相对于 Ag/AgCl）的施加电位下，ZnO/ZnSe 纳米钉阵列异质结构的光电流密度达到 1.01 mA cm(-2)，远高于 ZnO/ZnSe 纳米棒阵列（0.71 mA cm(-2)）、原始 ZnO 纳米棒阵列（0.39 mA cm(-2)）和 ZnSe 电极（0.21 mA cm(-2)），表明其在光电化学水氧化中具有显著的可见光驱动活性。这种钉帽纳米棒的独特形态可能对于深入了解异质结构与光电化学活性之间的关系很重要。
