Photovoltage Management Based on Enhanced Excitation Levels in Surface Arrays of Subwavelength Silicon Formations. Issue 12 (14th October 2020)

• Record Type: Journal Article
• Authors: Prajapati, Ashish; Shalev, Gil
• Is Part Of: Solar RRL. Volume 4:Issue 12(2020)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2020-10-14
• Subjects: broadband absorption -- excitation levels -- nanopillar arrays -- open-circuit voltage -- photon management -- photovoltage -- solar radiation; Solar energy -- Periodicals; Photovoltaic power generation -- Periodicals; Solar energy -- Research -- Periodicals; Photovoltaic power generation -- Research -- Periodicals; Periodicals; 333.7923
• DOI: 10.1002/solr.202000514
• Languages: English
• ISSNs: 2367-198X

Abstract

Abstract : Surface arrangements of subwavelength formations are extensively discussed in the context of photocurrent enhancement for photovoltaic (PV) applications. Recently, the potential contribution of such arrangements toward photovoltage augmentation is suggested. This study numerically demonstrates the potential for photovoltage management based on arrays composed of inverted silicon cones, referred to as light funnel (LF) arrays. The transition from an optimized nanopillar (NP) array into an LF array is examined. It is shown that a decrease in NP bottom diameter ( D b ) is accompanied by an increase in open‐circuit voltage ( V oc ). The highest photovoltage enhancement is recorded for the smallest considered D b = 50 nm with a V oc increase of 75 mV and reflects a 22% V oc enhancement compared with the NP V oc . It is shown that this V oc increase is due to 250% increase in the excitation level, and that the spatially resolved excitation level of the array‐nested LFs is more than two orders of magnitude higher than the highest spatially resolved excitation level in the array‐nested NPs. Finally, it is shown that the suggested photovoltage management entails almost a factor of 2 increase in the nominal power conversion efficiency upon the transition from an NP PV cell into LF PV cell. Abstract : Photovoltage enhancement in solar cells based on arrays of inverted silicon cones is presented. The photovoltage increases with a decrease in bottom diameter, which is due to the high excitation level of the individual inverted cones composing the array. The excitation level of the array‐nested inverted cones is more than two orders of magnitude higher than the excitation of array‐nested nanopillars.