Regulated Crystallization Through Intermolecular Interactions Bridging for Efficient Tin-Based Perovskite Solar...

Area of Science:

• Materials Science
• Renewable Energy
• Photovoltaics

Background:

• Tin halide perovskites (THPs) are promising lead-free materials for solar energy conversion.
• Rapid crystallization and Sn2+ oxidation in THPs cause poor film morphology and defects, limiting efficiency and stability.

Purpose of the Study:

• To develop a crystallization regulation strategy for THP solar cells using methyl carbazate (MeC).
• To improve the morphology, efficiency, and stability of THP films by controlling crystallization kinetics.

Main Methods:

• Introducing methyl carbazate (MeC) into the perovskite precursor solution.
• Investigating intermolecular interactions (coordination and hydrogen bonds) between MeC and perovskite.
• Analyzing the impact of MeC on Sn2+ oxidation, crystallization kinetics, and defect density.

Main Results:

• MeC formation of coordination and hydrogen bonds stabilized the perovskite lattice and suppressed Sn2+ oxidation.
• MeC enhanced nucleation sites, controlling fast crystallization and improving film morphology.
• MeC reduced deep-level trap state defects, suppressing non-radiative recombination and extending carrier lifetime.

Conclusions:

• Methyl carbazate offers a facile strategy to regulate THP crystallization, enhancing film quality.
• This approach significantly boosts THP solar cell power conversion efficiency from 10.43% to 14.02% with improved stability.