A facile preparation of ultrasmall 1-2 nm void metallic nanogaps on various solid substrates is proposed by utilizing the self-assembly of a uniform gold-silica core-shell nanoparticle monolayer at interfaces and chemical etching. The ultrasmall void metallic nanogap shows key advantages such as a strong near-field enhancement and free diffusion of analytes to the gap, which are useful in molecular sensing and monitoring.

Ultrasmall void metallic nanogaps offer key advantages, such as a strong near‐field enhancement and free diffusion of analytes to the gap, which are useful in molecular sensing and monitoring. On page 4344, T. Kang and co‐workers report the facile preparation of high‐density, ultra‐small 1–2 nm void metallic nanogaps on various solid substrates by utilizing the self‐assembly of a uniform gold–silica core–shell nanoparticle monolayer at interfaces along with chemical etching.