In2O3 nanorod arrays grown at grain-boundary triple junctions of Cu–Sn alloy substrate

In this article, an alternative method for site-specific growth of In2O3 nanorod arrays, which relies on the vapor–liquid–solid growth mechanism, is demonstrated using Cu–Sn (5 at% Sn) alloy as substrate. By annealing Cu–Sn alloy slightly below the solidus line, grain-boundary triple junctions can be wetted preferentially. As a result, the catalyzing Cu droplets will be present at the sites of grain-boundary triple junctions, which will control the growth of In2O3 nanorods at defined locations. This growth technique provides a cost-effective and simple approach to fabricate ordered nanorod arrays with the sites controlled, which may benefit nanorod device applications.