Interface engineering for efficient charge collection in Cu2O/ZnO heterojunction solar cells with ordered ZnO cavity-like nanopatterns

The ordered ZnO cavity-like nanopatterns were fabricated through the versatile nanosphere lithography (NSL) technique combined with the hydrothermal growth. Nanostructured Cu2O/ZnO heterojunction solar cell was fabricated by the electrodeposition of Cu2O into the ordered ZnO cavity-like nanopatterns. The formation of intercrossed interface between Cu2O and ZnO could increase the p–n heterojunction area effectively compared to the planar structure. The most efficient cavity-like cell showed a highest PCE of 0.51% with a Voc of 0.24 V, a Jsc of 6.33 mA cm−2, and a FF of 34.5. Significant increase in Jsc and PCE observed in the cavity-like cell was due to the increased p–n heterojunction area and then the enhanced charge carriers collection ability. Our results sheded light on a simple and economic approach to fabricate electrodeposited nanostructural Cu2O/ZnO solar cells with a high efficiency.