Synchronous Passivation of Defects with Low Formation Energies via Terdentate Anchoring Enabling High Performance Perovskite Solar Cells with Efficiency over 24%

Abstract

The ionic nature endows halide perovskites with intrinsic interfacial defects in the formed polycrystalline films, thus imposing the challenge of synchronously passivating these defects with low formation energies that directly account for the unsatisfied performance of perovskite solar cells (PSCs). By virtue of the theoretically proven capability of a three to four times enhancement of the formation energy of each defect of Pb‐I antisite (PbI) and iodine vacancy (VI), a new passivation molecule of 1,10‐phenanthrolin‐5‐amine (PAA) is intentionally explored to synchronously passivate the dual defects. The pronounced passivation effect is experimentally verified by the sharp enhancement of the open‐circuit voltage in ternary PSCs from the original 1.118 up to 1.207 V, as well as the construction of PAA‐modified formamidinium lead iodide PSCs with a champion efficiency up to 24.06%, thus providing a universal alternative of addressing interfacial charge carrier dynamics and operational stability of PSCs that are bothered by the multiple interfacial defects.

A Multifunctional Fluorinated Polymer Enabling Efficient MAPbI3-Based Inverted Perovskite Solar Cells

“…Vacancies and interstitials are generally considered as the shallow level defects, causing local band bending and phase segregation. 19 As a result, a decreased V oc could be observed. 20 A notable example is the uncoordinated Pb 2+ defect, has an effect on the carriers' extraction efficiency, thus the FF and short-circuit current density (J sc ) could be decreased.…”

“…According to reports, the abatement of the V oc and FF was detrimentally affected by the interfacial defects-induced nonradiative recombination (NRR). − Due to the inherent polycrystalline nature, the perovskite (taking MAPbI 3 as an example) crystallization process inevitably brings about intrinsic defects within the perovskite grain boundaries (GBs) and interfaces including vacancies (i.e., V MA , V Pb , and V I ), interstitials (i.e., MA i , Pb i , and I i ), and antisite substitutions (i.e., Pb I , MA I, MA Pb , I Pb , I MA , and Pb MA ). ,, Among all the defects, the antisite substitutions are classified as deep-level defects, which are prone to capture photogenerated carriers and reduce the charge density at steady state. Vacancies and interstitials are generally considered as the shallow level defects, causing local band bending and phase segregation . As a result, a decreased V oc could be observed .…”

[PbX6]4−modulation and organic spacer construction for stable perovskite solar cells

“…Perovskite solar cells (PSCs) have rapidly emerged as leading competitors in the photovoltaic field due to their easy and low-cost solution preparation and efficient photovoltaic conversion capability, which have attracted widespread attention in academia and industry. [1][2][3][4][5][6] Over the past decade, researchers have been devoted to developing perovskite materials and optimizing their preparation process to boost the power conversion efficiency (PCE) of PSCs. At present, the highest PCE achieved is 25.7%, 7 which has surpassed the performance of traditional thin-film solar cells and is close to that of monocrystalline silicon photovoltaic cells.…”

Bionic Levodopa-Modified TiO2 for Preparation of Perovskite Solar Cells with Efficiency over 23%

“…11 Therefore, the defects in perovskite films are important factors that cause the PCE to deviate from the theoretical value. 12 The problems caused by these defects could be solved using different approaches, such as solvent engineering, 13 component engineering, 14,15 and additive engineering. 16 PSCs generally comprise the following: conductive base, electron transport material, perovskite layer, hole transport material, and metal contact.…”