  One-dimensional (1D) materials have attracted significant research interest
due to their unique quantum confinement effects and edge-related properties.
Atomically thin 1D nanoribbon is particularly interesting because it is a
valuable platform with physical limits of both thickness and width. Here, we
develop a catalyst-free growth method and achieves the growth of Bi2O2Se
nanostructures with tunable dimensionality. Significantly, Bi2O2Se nanoribbons
with thickness down to 0.65 nm, corresponding to monolayer, are successfully
grown for the first time. Electrical and optoelectronic measurements show that
Bi2O2Se nanoribbons possess decent performance in terms of mobility, on/off
ratio, and photoresponsivity, suggesting their promising 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 thickness limit.
