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New Acidic Precursor and Acetone-Based Solvent for Fast Perovskite Processing via Proton-Exchange Reaction with Methylamine.

ABSTRACT: A new solvent system for PbI2 based on HI solution in acetone with a low boiling point is proposed. High solubility of PbI2 is caused by the formation of iodoplumbate complexes, and reaches a concentration of 1.6 M. Upon its crystallization metastable solvate phases PbI2?HI?n{(CH3)2CO} are formed. The latter allows for their easy deposition on substrates in a form of smooth and uniform thin films by spin-coating. Through a fast acid-base reaction with a gaseous amine, the films of the intermediate phase can be completely converted to single-phase perovskite films. The developed method allows one to form smooth perovskite films with high crystallinity with a thickness up to 1 ?m. Due to easy and fast processing, the developed method can be promising for perovskite technology upscaling.

SUBMITTER: Fateev SA

PROVIDER: S-EPMC7221818 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature

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New Acidic Precursor and Acetone-Based Solvent for Fast Perovskite Processing via Proton-Exchange Reaction with Methylamine.

Fateev Sergey A SA Marchenko Ekaterina I EI Petrov Andrey A AA Goodilin Eugene A EA Tarasov Alexey B AB

Molecules (Basel, Switzerland) 20200417 8

A new solvent system for PbI2 based on HI solution in acetone with a low boiling point is proposed. High solubility of PbI2 is caused by the formation of iodoplumbate complexes, and reaches a concentration of 1.6 M. Upon its crystallization metastable solvate phases PbI2∙HI∙n{(CH3)2CO} are formed. The latter allows for their easy deposition on substrates in a form of smooth and uniform thin films by spin-coating. Through a fast acid-base rea ...[more]

PMID: 32316550

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