From Bulk to Surface Passivation: Double Role of Chlorine‐Doping for Boosting Efficiency of FAPbI3‐rich Perovskite Solar Cells. Issue 8 (4th April 2022)

• Record Type: Journal Article
• Authors: Larini, Valentina; Degani, Matteo; Pica, Giovanni; Ding, Changzeng; Andaji-Garmaroudi, Zahra; Faini, Fabiola; Stranks, Samuel D.; Ma, Chang-Qi; Grancini, Giulia
• Is Part Of: Solar RRL. Volume 6:Issue 8(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-04-04
• Subjects: 3D/2D perovskites -- Cl-doping -- FAPbI3 -- perovskite solar cells -- PL imaging perovskite -- surface passivation; Solar energy -- Periodicals; Photovoltaic power generation -- Periodicals; Solar energy -- Research -- Periodicals; Photovoltaic power generation -- Research -- Periodicals; Periodicals; 333.7923
• DOI: 10.1002/solr.202200038
• Languages: English
• ISSNs: 2367-198X

Abstract

Abstract : Defect‐mediated recombination losses limit the open‐circuit voltage ( V OC ) of perovskite solar cells (PSCs), negatively affecting the device's performance. Bulk and dimensional engineering have both been reported as promising strategies to passivate shallow defects, thus improving the photovoltaic conversion efficiency (PCE). Here, a combined bulk and surface treatment employing chlorine‐based compounds is employed. Methylammonium chloride (MACl) is used as a bulk additive, while 4‐methylphenethylammonium chloride (MePEACl) is deposited onto the perovskite surface to produce a low‐dimensional perovskite (LDP) and reduce nonradiative recombination. Through structural and morphological investigations, it can be confirmed that bulk and surface doping have a beneficial effect on the film morphology and its overall quality, while electroluminescence (EL) and photoluminescence (PL) analyses demonstrate an increased and more homogeneous emission. Applying this double passivation strategy in PSC fabrication, a boost is observed in both the short‐circuit current density and the V OC of the devices, achieving a champion 21.4% PCE while improving device stability. Abstract : Bulk and surface treatment of formamidium lead iodide perovskite with chlorine‐based compounds promote an enhancement of the solar cell photovoltaic conversion efficiency (PCE), by simultaneously improving the active layer crystallinity and morphology, thus increasing the short‐circuit current density, and suppressing nonradiative losses, boosting the device open‐circuit voltage.