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Influence of Hybrid Perovskite Fabrication Methods on Film Formation, Electronic Structure, and Solar Cell Performance
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Cation Induced Structural Variation in Topochemically Modified Dion-Jacobson Perovskite Solid Solutions
Roshni Bhuvan1, Gary J Sandrock1, Sara Akbarian-Tefaghi1
1Department of Chemistry and the Advanced Materials Research Institute, The University of New Orleans, New Orleans, LA 70148, USA.
Molecules (Basel, Switzerland)
|November 27, 2025
Summary
Researchers explored solid solutions in Dion-Jacobson layered perovskites by varying alkali metal cations. They found that cation size influences structure and thermal stability, enabling structural control in perovskite materials.
Area of Science:
- Materials Science
- Solid-State Chemistry
- Crystallography
Background:
- Dion-Jacobson layered perovskites are ion-exchangeable materials with potential applications.
- Understanding the relationship between composition and structure is crucial for material design.
Purpose of the Study:
- To investigate the continuous solid solution series A1-xA'xLaNb2O7.
- To elucidate the structure-composition relationship in these perovskites.
- To explore the effect of alkali metal cation variation on structural and thermal properties.
Main Methods:
- Topochemical synthesis of solid solutions by reacting end members (ALaNb2O7).
- Characterization of solid solutions formed between various alkali metal combinations (Li, Na, K, Rb, Cs).
- Thermal analysis of selected solid solutions.
Main Results:
- Continuous solid solutions were formed for adjacent alkali metal pairs (Li/Na, Na/K, K/Rb, Rb/Cs).
- A non-adjacent solid solution (K/Cs) was also successfully synthesized.
- Cation coordination and layer alignments were found to be composition-dependent, dictated by the larger cation's concentration.
- Compositions containing Li and Na exhibited thermal instability.
Conclusions:
- Systematic variation of average cation sizes in the solid solution series allows for structural control.
- These findings contribute to the understanding and design of perovskite materials for various applications.
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