Effective surface design for highly-luminescent and water-dispersible metal halide perovskite nanocrystals

2022 Fiscal Year Final Research Report

• Project/Area Number: 21K14706
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 36010:Inorganic compounds and inorganic materials chemistry-related
• Research Institution: University of Yamanashi (2022); Tokyo University of Science (2021)
• Principal Investigator: Saito Norio 山梨大学, 大学院総合研究部, 助教 (20822456)
• Project Period (FY): 2021-04-01 – 2023-03-31
• Keywords: ペロブスカイト / ナノ結晶 / ハロゲン化物 / 配位子 / 耐水性 / 発光

Outline of Final Research Achievements

The aim of this study is to synthesize lead halide perovskite CsPbBr3 nanocrystals (NCs) passivated with a cationic oligomeric ligand and to clarify the relationship between its molecular structure, dispersion and emission properties, and stability against polar solvents. The oligomeric ligands exhibited luminescence properties and dispersion stability comparable to those of the existing ligand such as dimethyldidodecylammonium bromide and significantly higher water-durability than the existing ligands. The surface adsorption structure of the oligomeric ligand and the characteristic water- and ligand-mediated crystalline phase change were identified as the factors responsible for the improved water-durability. Furthermore, a new surface modification process via oil-in-water emulsions was developed as a new surface modification method for both surface protection and hydrophilization of the perovskite NCs.

Free Research Field

無機材料化学

Academic Significance and Societal Importance of the Research Achievements

ペロブスカイトナノ結晶は、その特徴的な光電子特性から次世代の機能性材料と期待されているものの、化学安定性の低さが課題である。本研究を通じて、ペロブスカイトナノ結晶の表面状態の制御に基づき、その分散安定性、発光特性や化学耐久性を大幅に向上できること、水やアルコールなどの極性溶媒中でも安定分散し、光電子特性を長時間維持できることを明らかにした。本研究で培った手法は、発光デバイスや太陽電池、触媒開発などに適用することができ、ペロブスカイトナノ結晶の新たな応用展開を拓くと期待される。今後はこれらの応用に向けた検討を行い、環境エネルギー問題の解決に資する革新的マテリアル創出に関する研究を展開する。