Systematic Investigation of the Optoelectronic Properties of GaAs Nanowire and Nanocone Solar Cells: Effect of Geometrical Nonuniformities, Angle of Incidence, and Structural and Electronic Parameters

Abstract

There are numerous research articles on the optoelectronic modeling of GaAs nanostructures such as nanowires (NWs) and nanocones (NCs), which have demonstrated promising possibilities for future solar cell (SC) applications. However, the relationship between the optical and electrical performance of the GaAs NW and NC array-based SCs is not well documented. In this paper, we present a thorough optoelectronic modeling of both the nanostructures and compare their overall photovoltaic performance for different conditions. We found that GaAs NCs can achieve outstanding optical absorption and negligible reflection losses over the entire absorption spectrum. Furthermore, the NC structure, for its optimal geometric configuration, achieved an average absorption (A(λ)) of 94%, photocurrent (J sc ) of 31 mA/cm 2 , and photogeneration rate (G optical ) of 5.2 × 10 22 cm −3 s −1 . Additionally, for oblique incidence, the GaAs NC has demonstrated substantially improved light-trapping and antireflection characteristics. Under different geometric nonuniformities, GaAs NC array outperformed the GaAs NW array with an A(λ) of 91.3%, J sc of 30.5 mA/cm 2 , and G optical of 3.45 × 10 22 cm −3 s −1 . The electrical simulations reveal that the GaAs NC can achieve a remarkable power conversion efficiency (PCE) of 19.2%, despite having a very short minority carrier lifetime (τ) and carrier mobility of (μ) of 2 ns and 1100 cm 2 V −1 s −1 , respectively.