Effect of perovskite thickness on electroluminescence and solar cell conversion efficiency

• Main Authors: Rai, Monika, Wong, Lydia Helena, Etgar, Lioz
• Other Authors: School of Materials Science and Engineering
• Format: Article
• Language: English
• Published: 2020
• Subjects: Engineering::Materials; Solar Cells; Perovskites
• Online Access: https://hdl.handle.net/10356/145078
• Institution: Nanyang Technological University

A hybrid organic−inorganic perovskite in a diode structure can lead to multifunctional device phenomena exhibiting both a high power conversion efficiency (PCE) of a solar cell and strong electroluminescence (EL) efficiency. Nonradiative losses in such multifunctional devices lead to an open circuit voltage (Voc) deficit, which is a limiting factor for pushing the efficiency toward the Shockley−Queisser limit. In this work, we analyze and quantify the radiative limit of Voc in a perovskite solar cell as a function of its absorber thickness. We correlate PCE and EL efficiency at varying thicknesses to understand the limiting factors for a high Voc. With a certain increase in perovskite thickness, PCE improves but EL efficiency is compromised and vice versa. Thus, correlating these two figures of merit of a solar cell guides the light management strategy together with minimizing nonradiative losses. The results demonstrate that maximizing absorption and emission processes remains paramount for optimizing devices.