The Efficiency Limit of CH3NH3PbI3 Perovskite Solar Cells

TL;DR

This paper predicts the efficiency limit of CH3NH3PbI3 perovskite solar cells considering photon recycling, light trapping, and angular restriction, showing they can approach the Shockley-Queisser limit with optimized design.

Contribution

It provides a detailed balance model incorporating experimental refractive index and spectrum, revealing how light management strategies can maximize perovskite solar cell efficiency.

Findings

Efficiency limit around 31% without angular restriction

Potential to reach 33% efficiency with wavelength-dependent angular restriction

Trap-assisted nonradiative recombination significantly impacts device performance

Abstract

With the consideration of photon recycling effect, the efficiency limit of methylammonium lead iodide (CH3NH3PbI3) perovskite solar cells is predicted by a detailed balance model. To obtain convincing predictions, both AM 1.5 spectrum of Sun and experimentally measured complex refractive index of perovskite material are employed in the detailed balance model. The roles of light trapping and angular restriction in improving the maximal output power of thin-film perovskite solar cells are also clarified. The efficiency limit of perovskite cells (without the angular restriction) is about 31%, which approaches to Shockley-Queisser limit (33%) achievable by gallium arsenide (GaAs) cells. Moreover, the Shockley-Queisser limit could be reached with a 200 nm-thick perovskite solar cell, through integrating a wavelength-dependent angular-restriction design with a textured light-trapping structure. Additionally, the influence of the trap-assisted nonradiative recombination on the device efficiency is investigated. The work is fundamentally important to high-performance perovskite photovoltaics.