title: Rapid atomic layer deposition of silica nanolaminates: synergistic catalysis of Lewis/Brønsted acid sites and interfacial interactions.
abstract: Rapid atomic layer deposition (RALD) has been applied to prepare various nanolaminates with repeated multilayer structures. The possible reaction pathways for RALD of the Al2O3/SiO2 nanolaminate using trimethylaluminum (TMA) and tris(tert-butoxy)silanol (TBS) are investigated by using density functional theory (DFT) calculations. The introduction of a Lewis-acid catalyst, TMA, can result in the formation of the catalytic site, which accelerates the propagation of the siloxane polymer. The rate-determining step of whole RALD is the elimination of isobutene of the tert-butoxy groups. The Brønsted acid site of [AlO4] can catalyze the elimination of isobutene. At the same time, the interfacial interactions, such as hydrogen bonding interactions between tert-butoxy groups and the surface, further catalyze the elimination of isobutene and accelerate SiO2 RALD reactions. The synergistic catalysis of Lewis/Brønsted acid sites and interfacial interactions may be applied in the RALD fabrication of other silica nanolaminates, such as HfO2/SiO2, ZrO2/SiO2, and TiO2/SiO2, in microelectronics, catalysis, energy storage, and conversion.
authors.affiliation: Institute of Theoretical and Computational Chemistry, Key Laboratory of Mesoscopic Chemistry of Ministry of Education, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, P. R. China. majing@nju.edu.cn.
authors.forename: Guoyong
authors.initials: G
authors.lastname: Fang
authors.forename: Jing
authors.initials: J
authors.lastname: Ma