Enhancing UV photoconductivity of ZnO nanobelt by polyacrylonitrile functionalization

In this work, we present a bilayer polymer/ZnO photoconductor based on ZnO NBs and plasma polymerized acrylonitrile PP-AN nanoscale surface coating. By taking advantage of a rectangular cross section of NBs, uniform bilayered PP-AN/ZnO NBs were fabricated by exploiting plasma enhanced chemical vapor deposition PECVD .W e demonstrated that under identical UV illumination conditions, the photocurrent of ZnO NBs was increased by a factor of 750 after coating with PP-AN. The suggested mechanism includes a consequence of the efficient exciton dissociation under UV illumination due to enhanced electron transfer from valence band of ZnO NB to the photon-excited PP-AN rich on double and triple carbon-nitrogen bonds and then back to the conduction band of ZnO. The present study on the PP-AN-functionalized NBs presents a simple and costeffective method for improving the performance of oxide NW/NB-based devices, possibly leading to a new generation of potential photodetector for applications such as imaging, photosensing, and intrachip optical interconnects.

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