“…Heterogeneous nanostructures, unique nanoarchitecture with bi- or multimetallic construction, have gained considerable attention in the development of catalysts, , sensors, − transistors, nanogenerators, photovoltaic devices, batteries, metasurfaces, , and plasmonic structures. , In these devices, the core elements with unprecedented performance are nano-manufactured functional materials, such as nanoparticles, nanorods, nanowires, nanopillars, nanoboxes, and nanoribbons, whose physical properties and functions are fundamentally different from those of the bulk materials. , In particular, the combination of unique nanostructures and multiple noble metal construction provides enhanced catalytic properties and optical properties. For example, several studies have reported reliable and sensitive gas sensors based on heterogeneous nanowires with various noble-metal (e.g., Ag, Au) catalysts. − Additionally, various other noble metal-based heterogeneous nanostructures with ultra-small nanogaps (including nanoparticles, nanopillars, nanoboxes) have been extensively fabricated.…”