Effect of the polymer emission on the electroluminescence characteristics of n-ZnO nanorods/p-polymer hybrid light emitting diode Effect of the Polymer Emission on the Electroluminescence Characteristics of n-ZnO Nanorods/p-Polymer Hybrid Light Emitting D

Abstract

Abstract Hybrid light emitting diodes (LEDs) based on zinc oxide (ZnO) nanorods and polymers (single and blended) are fabricated and characterized. The ZnO nanorods were grown by the chemical bath deposition method at 50 o C. Three different LEDs, either with blue emitting, orange-red emitting or their blended polymer together with ZnO nanorods were fabricated and studied. The current-voltage characteristics show good diode behavior with ideality factor in the range of 2.1 to 2.27 for all the three devices. The electroluminescence spectrum (EL) of the blended device has an emission range from 450nm to 750nm, due to the intermixing of the blue emission generated by the poly(9,9-dioctylfluorene) denoted as PFO with orange red emission produced by the poly(2-methoxy-5(20-ethyl-hexyloxy)-1,4-phenylenevinylene) 1,4-phenylenevinylene) symbolize as MEH PPV combined with the deep band emission (DBE) of the ZnO nanorods i.e. it covers the whole visible region and manifested as white light. The CIE colour coordinates showed bluish, orange-red and white emission from the PFO, MEH PPV and blended LEDs with ZnO nanorods, respectively. These results indicate that the choice of the polymer with proper concentration is critical to the emitted colour in ZnO nanorods/p-organic polymers LEDs and careful design should considered to obtain intrinsic white light sources