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Zaera F. The surface chemistry of the atomic layer deposition of metal thin films. NANOTECHNOLOGY 2024; 35:362001. [PMID: 38888294 DOI: 10.1088/1361-6528/ad54cb] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2024] [Accepted: 06/06/2024] [Indexed: 06/20/2024]
Abstract
In this perspective we discuss the progress made in the mechanistic studies of the surface chemistry associated with the atomic layer deposition (ALD) of metal films and the usefulness of that knowledge for the optimization of existing film growth processes and for the design of new ones. Our focus is on the deposition of late transition metals. We start by introducing some of the main surface-sensitive techniques and approaches used in this research. We comment on the general nature of the metallorganic complexes used as precursors for these depositions, and the uniqueness that solid surfaces and the absence of liquid solvents bring to the ALD chemistry and differentiate it from what is known from metalorganic chemistry in solution. We then delve into the adsorption and thermal chemistry of those precursors, highlighting the complex and stepwise nature of the decomposition of the organic ligands that usually ensued upon their thermal activation. We discuss the criteria relevant for the selection of co-reactants to be used on the second half of the ALD cycle, with emphasis on the redox chemistry often associated with the growth of metallic films starting from complexes with metal cations. Additional considerations include the nature of the substrate and the final structural and chemical properties of the growing films, which we indicate rarely retain the homogeneous 2D structure often aimed for. We end with some general conclusions and personal thoughts about the future of this field.
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Affiliation(s)
- Francisco Zaera
- Department of Chemistry, University of California, Riverside, CA 92521, United States of America
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Smela D, Chang CJ, Hromadko L, Macak J, Bilkova Z, Taniguchi A. SiO 2 Fibers of Two Lengths and Their Effect on Cellular Responses of Macrophage-like Cells. Molecules 2022; 27:4456. [PMID: 35889328 PMCID: PMC9320682 DOI: 10.3390/molecules27144456] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Revised: 06/30/2022] [Accepted: 07/09/2022] [Indexed: 01/27/2023] Open
Abstract
The immunoreactivity or/and stress response can be induced by nanomaterials' different properties, such as size, shape, etc. These effects are, however, not yet fully understood. This study aimed to clarify the effects of SiO2 nanofibers (SiO2NFs) on the cellular responses of THP-1-derived macrophage-like cells. The effects of SiO2NFs with different lengths on reactive oxygen species (ROS) and pro-inflammatory cytokines TNF-α and IL-1β in THP-1 cells were evaluated. From the two tested lengths, it was only the L-SiO2NFs with a length ≈ 44 ± 22 µm that could induce ROS. Compared to this, only S-SiO2NFs with a length ≈ 14 ± 17 µm could enhance TNF-α and IL-1β expression. Our results suggested that L-SiO2NFs disassembled by THP-1 cells produced ROS and that the inflammatory reaction was induced by the uptake of S-SiO2NFs by THP-1 cells. The F-actin staining results indicated that SiO2NFs induced cell motility and phagocytosis. There was no difference in cytotoxicity between L- and S-SiO2NFs. However, our results suggested that the lengths of SiO2NFs induced different cellular responses.
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Affiliation(s)
- Denisa Smela
- Department of Biological and Biochemical Sciences, Faculty of Chemical Technology, University of Pardubice, Studentska 573, 532 10 Pardubice, Czech Republic;
- Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan; (C.-J.C.); (A.T.)
| | - Chia-Jung Chang
- Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan; (C.-J.C.); (A.T.)
| | - Ludek Hromadko
- Center of Materials and Nanotechnologies, Faculty of Chemical Technology, University of Pardubice, Nam. Cs. Legii 565, 530 02 Pardubice, Czech Republic; (L.H.); (J.M.)
- Central European Institute of Technology, Brno University of Technology, Zerotinovo nam. 617/9, 601 77 Brno, Czech Republic
| | - Jan Macak
- Center of Materials and Nanotechnologies, Faculty of Chemical Technology, University of Pardubice, Nam. Cs. Legii 565, 530 02 Pardubice, Czech Republic; (L.H.); (J.M.)
- Central European Institute of Technology, Brno University of Technology, Zerotinovo nam. 617/9, 601 77 Brno, Czech Republic
| | - Zuzana Bilkova
- Department of Biological and Biochemical Sciences, Faculty of Chemical Technology, University of Pardubice, Studentska 573, 532 10 Pardubice, Czech Republic;
| | - Akiyoshi Taniguchi
- Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan; (C.-J.C.); (A.T.)
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