Managing Interfacial Charged Defects with Multiple Active Sited Macrocyclic Valinomycin for Efficient and Stable Inverted Perovskite Solar Cells

With the continuous development of the performance of perovskite solar cells, the high-density defects on the perovskite film surface and grain boundaries as well as undesired perovskite crystallization are increasingly emerging as challenges to their commercial application. Herein, a dye intermediate 2-anisidine-4sulfonic acid (2A4SA), containing sulfonic acid group (SO 3 − ), amino group (−NH 2 ), methoxy group (CH 3 O−), and benzene ring, which exhibit a synergistic effect in comprehensive defect passivation and crystallization modulation, is incorporated. Detailed investigations show that the SO 3 − of 2A4SA with high electronegativity firmly chelates with uncoordinated lead ions through the coordination interaction, while the −NH 2 and the CH 3 O− of 2A4SA separately immobilize iodide ions and organic cations in the perovskite lattice through hydrogen bonds, enabling substantially decreased nonradiative recombination and trap state density. Meanwhile, 2A4SA molecules attached to the surface of perovskite nuclei can delay crystallization kinetics and promote preferred vertical growth orientation, thereby attaining the high-crystallinity and large-size-grain perovskite films. Consequently, the 2A4SA-doped device with the structure ITO/SnO 2 /Cs 0.15 FA 0.75 MA 0.10 PbI 3 (2A4SA)/Spiro-OMeTAD/Ag presents a splendid power conversion efficiency (PCE) of 23.06% accompanied by increased open-circuit voltage (1.15 V) and fill factor (82.17%). Furthermore, the optimized film and device demonstrate enhanced long-term stability. The unencapsulated optimized device retains ≈80% of the original PCE after 1000 h upon exposure to ambient atmosphere (20−50% RH), whereas the control group is only 56.8%.

Section: ■ Results and Discussionmentioning

confidence: 99%

Synergistic Defect Passivation and Crystallization Modulation in Efficient Perovskite Solar Cells: The Case of Multifunctional 2-Anisidine-4-Sulfonic Acid

Li,

Song,

Deng

et al. 2023

“…For the adsorption configurations of B 2 O 3 on the Pb 2+ top site, the separation between the side O atom of B 2 O 3 and the surface uncoordinated Pb 2+ is 2.515 Å. In view of the fact that the sum of van der Waals radii of Pb and O atoms is about 3.05, 2.515 Å is considered to be close enough to form a stable Pb–O bond. − Besides, it is noteworthy that the bond length of B 2 O 3 increases slightly (from the bottom to the top, the bond length respectively changes to 1.231, 1.338, 1.353, and 1.222 Å), whereas the bond angle of B–O–B significantly changes to 122.81°, further confirming the strong interaction between the O atom and uncoordinated Pb 2+ . For the adsorption configurations of B 2 O 3 on the V I top site, the distance between the side O atom of B 2 O 3 and V I is 3.134 Å, which is comparable to the bond length of Pb–I in FAPbI 3 (3.038 Å).…”

Section: Results and Discussionmentioning

confidence: 99%

Novel Strategy for High Efficient and Stable Perovskite Solar Cells through Atomic Layer Deposition

Jia,

Jiang,

et al. 2024

The perovskite material has demonstrated conceivable potential as an absorbing material of solar cells. Although the power conversion efficiency of the device based on perovskite has rapidly come to 26%, there are still many factors that affect the further improvement of the photoelectric conversion efficiency. Interface defects are the dominating concern that influence carrier transportation and stability. Here, we report a novel strategy where B 2 O 3 is deposited on the fresh perovskite film by atomic layer deposition technology. The organic atmosphere during atomic layer deposition can effectively regulate the crystallization kinetics of perovskites and promote crystal growth. The B 2 O 3 adsorbed on the perovskite light-absorption layer can effectively reduce the electropositive defects on the surface of the perovskite, such as uncoordinated Pb 2+ and I vacancies due to the electron-donating properties of the side O atoms in B 2 O 3 . Consequently, the power conversion efficiency of the perovskite solar cell after B 2 O 3 treatment increases to 21.78% from 18.89%. Simultaneously, B 2 O 3 can improve the stability of devices.

“…In conventional perovskite cells, the buried interface is crucial for the PCE and stability of PSCs. , It is reported that the concentration of defects at the ETL/perovskite buried interface is higher than that at the upper surface of perovskite . Specific defects at the buried interface include oxygen vacancies (V O ) and unchelated metal atoms inherent in the bulk and surface of SnO 2 as well as metal, halogen, and organic ions at the bottom interface of perovskite films. − These defects at the SnO 2 /perovskite buried interface not only lead to nonradiative recombination and reduced electron transport capacity but also cause unfavorable energy level matching and poor perovskite crystallinity. − To further improve the PCE and stability of PSCs, defect management at the buried interface deserves to be investigated.…”

Section: Introductionmentioning

confidence: 99%

Multifunctional Biomolecules Bridging a Buried Interface for Efficient Perovskite Solar Cells

Wang,

Li,

Deng

et al. 2024

The inevitably positively and negatively charged defects on the SnO 2 /perovskite buried interface often lead to nonradiative recombination of carriers and unfavorable alignment of energy levels in perovskite solar cells (PSCs). Interface engineering is a reliable strategy to manage charged defects. Herein, the nicotinamide adenine dinucleotide (NAD) molecules with multiple active groups of �P=O, �P−O, and �NH 2 are introduced to bridge the SnO 2 /perovskite buried interface for achieving simultaneous elimination of positively and negatively charged defects. We demonstrate that the �P=O and �P−O groups in NAD not only fix the uncoordinated Pb 2+ but also fill the oxygen vacancies (V O ) on the SnO 2 layer to eliminate positively charged defects. Meanwhile, �NH 2 groups form hydrogen bonds with PbI 2 to reduce the number of negatively charged defects. In addition, the NAD biomolecules as a bridge induce high perovskite crystallization and accelerated electronic transfer along with favorable energy band alignment between SnO 2 and perovskite. Finally, the PSCs with the ITO/SnO 2 /NAD/Cs 0.15 FA 0.75 MA 0.1 PbI 3 /Spiro-OMeTAD/Ag structure deliver an improvement in the power conversion efficiency from 20.49 to 23.18% with an excellent opencircuit voltage (V oc ) of 1.175 V. This work demonstrates that interface engineering through multifunctional molecular bridges with various functional groups is an effective approach to improve the performance of PSCs by eliminating charged defects and simultaneously regulating energy level alignment.