Device architecture engineering in polymer/ZnO quantum dots/ZnO array ternary hybrid solar cells

Abstract

Hybrid solar cells (HSCs) based on pristine ZnO nanorod array (ZnO-NRA) and conjugated polymer with ordinary inverted device architecture normally perform low open-circuit voltage (V oc) and short-circuit current density (J sc). This paper compares three improved device architectures for preparation of efficient polymer/ZnO-NRA HSCs by incorporating ZnO quantum dots (ZnO-QDs) into device with different engineering. It is found that when growth of ZnO-QDs on ZnO nanorod surface to formation of homostructured ZnO core–shell array (ZnO-CSA) instead of pristine ZnO-NRA can significantly increase the device V oc, while blending ZnO-QDs into MEH-PPV between nanorods can significantly increase the device J sc. The best photovoltaic performance is realized in the architecture consisting of ZnO-CSA as well as blends of MEH-PPV and ZnO-QDs, in which the V oc and J sc can be significant enhanced simultaneously. The present study reports the architecture-related device performances in polymer/ZnO-NRA solar cells, which will help to guide the design of HSCs or related optoelectronic devices.