  Oxygen conductors and transporters are important to several consequential
renewable energy technologies, including fuel cells and syngas production.
Separately, monolayer transition metal dichalcogenides (TMDs) have demonstrated
significant promise for a range of applications, including quantum computing,
advanced sensors, valleytronics, and next-gen optoelectronics. Here, we
synthesize a few nanometer-thick BixOySez compound that strongly resembles a
rare R3m bismuth oxide (Bi2O3) phase, and combine it with monolayer TMDs, which
are highly sensitive to their environment. We use the resulting 2D
heterostructure to study oxygen transport through BixOySez into the interlayer
region, whereby the 2D material properties are modulated, finding
extraordinarily fast diffusion at room temperature under laser exposure. The
oxygen diffusion enables reversible and precise modification of the 2D material
properties by controllably intercalating and deintercalating oxygen. Changes
are spatially confined, enabling submicron features (e.g. pixels), and are
long-term stable for more than 221 days. Our work suggests few nanometer-thick
BixOySez is a promising unexplored room-temperature oxygen transporter.
Additionally, our findings suggest the mechanism can be applied to other 2D
materials as a generalized method to manipulate their properties with high
precision and submicron spatial resolution.
