Highly Rectifying Water-Mediated Hydrogen Bond-Coupled Organic-Inorganic Interfaces

Asymmetrically conducting interfaces are the buildingblocks ofelectronic devices. While p-n junction diodes made of seminalinorganic semiconductors with rectification ratios close to the theoreticallimits are routinely fabricated, the analogous organic-inorganicand organic-organic interfaces are still too leaky to affordfunctional use. We report fabricating highly rectifying organic-inorganicinterfaces by forming water-mediated hydrogen bonds between the hydrophilicsurfaces of a hole-conducting polymer anode and a polycrystallinen-type metal oxide cathode. These hydrogen bonds simultaneously strengthenthe anode-cathode electronic coupling, facilitate the matchingbetween their incompatible surface structures, and passivate the detrimentalsurface imperfections. Compared to an analogous directly joined interface,our hydrogen-bonded Au-PEDOT:PSS-H2O-TiO2-Ti diodes demonstrate 10(5) times higher rectificationratios. These results illustrate the strong electronic coupling powerof the hydrogen bonds on a macroscopic scale and underscore the hydrogen-bondedinterfaces as the building blocks of fabricating organic electronicand optoelectronic devices. The presented interface model is anticipatedto advance designing electronic devices based on the organic-organicand organic-inorganic hetero-interfaces. Described electronicimplications of hydrogen bonding on the conductive polymer interfacesare anticipated to be impactful in the organic electronics and neuromorphicengineering.

Automated summary

Hydrogen bonding is utilized to fabricate highly rectifying organic-inorganic interfaces, which demonstrate significantly higher rectification ratios compared to directly joined interfaces. These hydrogen-bonded interfaces have great potential in the design of organic electronic and optoelectronic devices.