31 October 2013 Nanophotonic devices

Cross-sectional SEM image of a ZnO-PbS solar cell built on top of an imprinted electrode.

Imprinted electrodes for enhanced light trapping in quantum dot solar cells in Advanced Materials. Researchers at ICFO have developed a new light trapping scheme relying on a low-cost, large area and low-temperature soft nanoimprinting procedure. This promising technique is employed to fabricate nanostructured electrodes that have been optically designed to facilitate enhanced light trapping in thin films of colloidal quantum dot solar cells while acting as a charge collecting electrode. The results of this study led by Nest Fellow Professor Gerasimos Konstantatos have been recently published in Advanced Materials.

These imprinted electrodes produce a 17.5% increase in photocurrent as a result of improved light absorption without deteriorating other critical figures of merit of the solar cell (Voc, FF), favoring a seamless integration of these electrodes in solar devices. The enhanced photocurrent produces a power conversion enhancement of the same magnitude leading to ZnO-PbS heterojunction solar cells with power conversion efficiencies of 4.3%.