A major advantage of nanostructuring and nanostructuring based on colloidal templates of anodic alumina (AAO) and polystyrene (PS) is to obtain large-area nanostructure arrays with highly controllable size and spacing and predefined spatial orientation (Prog. Mater. Sci. 2007) 52 (465), Chem. Soc. Rev. 2011 (40, 1247). Using AAO and PS templates as masks or skeletons, many functional nanostructures and surface nanopatterns with building blocks in different dimensions such as 0D (nanodots, nanorings, nanobelts), 1D (nanorods, nanotubes), 2D ( nanosheets, nanowalls) and 3D (hierarchical structures, inverse opal) were fabricated in our group. The structure size of these nanostructures fabricated by the AAO and PS matrices can be tuned within about 10 nm - 1 μm and 50 nm - 5 μm, respectively, covering a wide size range from several nanometers to several micrometers. Due to their advantageous properties (high regularity, high structural controllability, low-cost processes), these template-controlled nanostructures are desirable candidate structures for the construction of high-performance devices (Adv. Energy Mater. 2020, in press, 2001537; Adv. Energy Mater. 2020, 10, 2001460; Nano Today 2018, 20, 33; Nano Energy 2015, 13, 790; Small 2015, 11, 3408).

Starting from a characteristic AAO template with binary pores containing two different sets of pores in a matrix, our group has recently proposed a brand-new concept to realize large-scale arrays of binary nanostructures with tailored size and flexible shape (Nature Nanotechnology 2017, 12, 244). Different components can be built into binary nanostructures (wire/wire, wire/tube, tube/tube & dot/dot) with a desired material selection for each component. Considering the different combinations of dimensions, materials and morphologies of components, binary nanostructuring is expected to be an excellent model to achieve unique properties for different applications. This binary patterning concept has been demonstrated to largely improve the device performance of plasmonic photocatalysis (Nano Lett. 2018, 18, 4914).