Catalyst‐Free Growth of Atomically Thin Bi 2 O 2 Se Nanoribbons for High‐Performance Electronics and Optoelectronics

1D materials have attracted significant research interest due to their unique quantum confinement effects and edge‐related properties. Atomically thin 1D nanoribbons are particularly interesting because it is a valuable platform with the physical limits of both thickness and width. Here, a catalyst‐free growth method is developed and the growth of Bi 2 O 2 Se nanostructures with tunable dimensionality is achieved. Significantly, Bi 2 O 2 Se nanoribbons with a thickness down to 0.65 nm, corresponding to a monolayer, are successfully grown for the first time. Electrical and optoelectronic measurements show that Bi 2 O 2 Se nanoribbons possess decent performance in terms of mobility, on/off ratio, and photoresponsivity, suggesting their promise for devices. This work not only reports a new method for the growth of atomically thin nanoribbons but also provides a platform to study properties and applications of such nanoribbon materials at a thickness limit.