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Theoretical Study of the Mechanism for the Reaction of Trimethylaluminum with Ozone.

ABSTRACT: The mechanism for the reaction of trimethylaluminum (TMA, Al(CH₃)₃) with ozone (O₃) was investigated in detail using density functional theory calculations to understand the atomic layer deposition processes that form aluminum oxide surfaces. We examined the reactions of TMA and some possible intermediates with O₃ and revealed plausible paths to form methoxy (-OCH₃), formate (-OCHO), bicarbonate (-CO₃H), and hydroxyl (-OH) species. These species have been observed in previous experimental studies. It was shown that TMA easily reacts with O₃ to generate the Al(CH₃)₂(OCH₃)(O₂) intermediate. The subsequent reaction between the OCH₃ and O₂ groups finally generated an intermediate having a formate group. When all of the CH₃ groups are converted into OCH₃ or OCHO, O₃ will react with these groups. In the latter reaction, bicarbonate was shown to be formed.

SUBMITTER: Kayanuma M

PROVIDER: S-EPMC8515592 | biostudies-literature | 2021 Oct

REPOSITORIES: biostudies-literature

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Theoretical Study of the Mechanism for the Reaction of Trimethylaluminum with Ozone.

Kayanuma Megumi M Choe Yoong-Kee YK Hagiwara Takayuki T Kameda Naoto N Shimoi Yukihiro Y

ACS omega 20210928 40

The mechanism for the reaction of trimethylaluminum (TMA, Al(CH3)3) with ozone (O3) was investigated in detail using density functional theory calculations to understand the atomic layer deposition processes that form aluminum oxide surfaces. We examined the reactions of TMA and some possible intermediates with O3 and revealed plausible paths to form methoxy (-OCH3), formate (-OCHO), bicarbonate (-CO3H), and hydroxyl (-OH) species ...[more]

PMID: 34660987

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