# Enabling Highly Efficient and Stable Perovskite Photovoltaics via A Multidentate Molecular Anchor Additive

## TL;DR

A new additive improves perovskite solar cells by stabilizing the material and boosting efficiency to 26.13%.

## Contribution

A multifunctional additive (ZL1) is introduced to stabilize perovskite films through multisite interactions, enhancing efficiency and stability.

## Key findings

- ZL1 suppresses formamidinium loss and improves perovskite crystallization.
- ZL1-treated devices achieve 26.13% efficiency and show enhanced operational stability.
- ZL1 also improves wide-bandgap PSCs from 18.44% to 20.53% efficiency.

## Abstract

A novel multifunctional additive (ZL1) enables formamidinium loss suppression and perovskite stabilization via synergistic multisite interactions.ZL1 demonstrates defect passivation, enhanced charge carrier extraction, and reduced charge recombination.
The optimized devices exhibit a high champion efficiency of 26.13%, combined with robust photothermal stability.

A novel multifunctional additive (ZL1) enables formamidinium loss suppression and perovskite stabilization via synergistic multisite interactions.

ZL1 demonstrates defect passivation, enhanced charge carrier extraction, and reduced charge recombination.

The optimized devices exhibit a high champion efficiency of 26.13%, combined with robust photothermal stability.

The online version contains supplementary material available at 10.1007/s40820-026-02098-8.

Suppressing formamidinium (FA) loss and perovskite phase degradation is very crucial for achieving highly efficient and long-term stable perovskite solar cells (PSCs). Herein, we designed and synthesized a novel multifunctional additive (ZL1) to stabilize α-FAPbI3 perovskite phase through synergistic multisite interactions: i its F atoms form F···H–N hydrogen bonds with FA+, (ii) its phenyl rings participate in cation–π interactions with FA+, (iii) the C=O and S groups coordinate Pb2+ through Lewis acid–base interactions, and (iv) the NH groups engage I− anions through N–H···I hydrogen bonding. Consequently, ZL1 molecule can effectively suppress FA loss and optimizes perovskite crystallization kinetics, yielding high-quality and stable α-FAPbI3 perovskite films with enlarged grain sizes and reduced defect density. Meanwhile, ZL1 treatment promotes exciton dissociation, facilitates hole extraction from the perovskite layer into the hole transport layer, and reduces charge carrier recombination in device. The ZL1-modified device achieves a power conversion efficiency of 26.13%, significantly outperforming the control device (24.20%). A similar improvement is observed in wide-bandgap PSCs, with efficiency increasing from 18.44% to 20.53% after ZL1 treatment. Notably, the unencapsulated ZL1-based devices exhibit exceptional operational stability under both illumination and thermal conditions.

The online version contains supplementary material available at 10.1007/s40820-026-02098-8.