Construction of ZnSe–ZnO axial p–n junctions via regioselective oxidation process and their photo-detection applications

Single ZnSe–ZnO nanowire axial p–n junction was fabricated by regioselectively oxidizing the p-type ZnSe NW in air. Pronounced current rectification behavior with on/off ratio of ∼50 and ideality factor of ∼1.7 were presented. The axial p–n junction also exhibited high sensitivity to UV light. A high performance UV light photodetector with a responsibility of ∼0.67 × 104 A W−1, a gain of ∼2.3 × 104 and a detectivity of ∼4.1 × 1013 cm Hz1/2 W−1 were elucidated based on this axial p–n junction. This new method is expected to construct more nano-devices based on one-dimensional semiconductor nanostructures.