Sander Mann, AMOLF

Title: Quantifying the limits and losses of single nanowire solar cells in a thermodynamic context
Session: 15:30

Abstract

Nanowire solar cells promise record performance by taking advantage of nanophotonic engineering. However, the standard definitions of power conversion efficiency and external quantum efficiency do not apply to single nanowire solar cells and therefore are not useful performance metrics. Here we analyze a record single nanowire solar cell and place its performance on an absolute thermodynamic scale for the first time. This requires a novel characterization method – integrating sphere microscopy – where we measure spatially resolved quantitative absorption, fluorescence and photocurrent to demonstrate an internal quantum efficiency >90% and an external radiative efficiency of 0.06%, similar to Si and CIGS record planar solar cells. The measured open-circuit voltage (850 mV) is only 300 mV below the thermodynamic limit, with 110 mV of this loss occurring at the contacts. Such detailed characterization pinpoints critical areas of improvement for InP nanowire solar cells to reach record efficiencies.

Bio

to be announced

Powered by Invitado Visitor Management