Institute for Materials, Ruhr-Universität Bochum, D-44801 Bochum, Germany.
Nanotechnology. 2017 May 5;28(18):185604. doi: 10.1088/1361-6528/aa6964.
Porous and photoelectrochemically active Fe-doped WO nanostructures were obtained by a combinatorial dealloying method. Two types of precursor materials libraries, exhibiting dense and nano-columnar morphology were fabricated by using two distinct magnetron sputter deposition geometries. Both libraries were subjected to combinatorial dealloying enabling preparation and screening of a large quantity of compositions having different nanostructures. This approach allows identifying materials with interesting photoelectrochemical characteristics. The dealloying process selectively dissolved Fe from the composition gradient precursor W-Fe materials library, resulting in formation of monoclinic single crystalline nanoblade-like structures over the entire surface. Photoelectrochemical properties of nanostructured Fe:WO films were found to be composition-dependent. The measurement region doped with ∼1.7 at % Fe and a film thickness of ∼ 900-1100 nm displayed highly porous WO nanostructures and exhibited the highest photocurrent density of ∼ 72 μA cm. This enhanced photocurrent density is attributed to the decreased bandgap values, suppressed recombination of electron-hole pairs, improved light absorption as well as efficient charge transport in the highly porous Fe-doped film with single crystalline WO nanoblades.
通过组合脱合金方法获得了多孔且光电活性的 Fe 掺杂 WO 纳米结构。使用两种不同的磁控溅射沉积几何形状制备了两种具有密集和纳米柱状形态的前驱体材料库。对两个库都进行了组合脱合金处理，从而能够制备和筛选具有不同纳米结构的大量组成物。这种方法可以确定具有有趣光电化学特性的材料。脱合金过程选择性地从组成梯度前驱体 W-Fe 材料库中溶解 Fe，从而在整个表面上形成单斜单晶纳米刀片状结构。发现纳米结构 Fe:WO 薄膜的光电特性与组成有关。在掺杂约 1.7 at% Fe 和薄膜厚度约 900-1100nm 的测量区域显示出高度多孔的 WO 纳米结构，并表现出最高的光电流密度约为 72μA cm。这种增强的光电流密度归因于带隙值降低、抑制电子-空穴对的复合、提高光吸收以及在具有单晶 WO 纳米刀片的高多孔 Fe 掺杂膜中有效电荷输运。
