Building organosilica hybrid nanohemispheres via thiol-ene click reaction on alumina thin films deposited by atomic layer deposition (ALD)

Gabriela Ambrožić; Maria Kolympadi Markovic; Robert Peter; Ivna Kavre Piltaver; Ivana Jelovica Badovinac; Duško Čakara; Dean Marković; Mato Knez

doi:10.1016/j.jcis.2019.10.074

Building organosilica hybrid nanohemispheres via thiol-ene click reaction on alumina thin films deposited by atomic layer deposition (ALD)

J Colloid Interface Sci. 2020 Feb 15:560:303-311. doi: 10.1016/j.jcis.2019.10.074. Epub 2019 Oct 21.

Authors

Gabriela Ambrožić¹, Maria Kolympadi Markovic², Robert Peter², Ivna Kavre Piltaver², Ivana Jelovica Badovinac², Duško Čakara³, Dean Marković⁴, Mato Knez⁵

Affiliations

¹ Department of Physics, University of Rijeka, Radmile Matejčić 2, 51000 Rijeka, Croatia; Centre for Micro- and Nanosciences and Technologies, University of Rijeka, Radmile Matejčić 2, 51000 Rijeka, Croatia. Electronic address: gabriela.ambrozic@uniri.hr.
² Department of Physics, University of Rijeka, Radmile Matejčić 2, 51000 Rijeka, Croatia; Centre for Micro- and Nanosciences and Technologies, University of Rijeka, Radmile Matejčić 2, 51000 Rijeka, Croatia.
³ Centre for Micro- and Nanosciences and Technologies, University of Rijeka, Radmile Matejčić 2, 51000 Rijeka, Croatia; Department of Biotechnology, University of Rijeka, Radmile Matejčić 2, 51000 Rijeka, Croatia.
⁴ Department of Biotechnology, University of Rijeka, Radmile Matejčić 2, 51000 Rijeka, Croatia.
⁵ CIC nanoGUNE, 20018 San Sebastian, Spain; IKERBASQUE, Basque Foundation for Science, 48013 Bilbao, Spain.

PMID: 31670103
DOI: 10.1016/j.jcis.2019.10.074

Abstract

The present work shows a surface-induced preparation of sub-100 nm organosilica nanohemispheres on atomic layer deposited (ALD) Al₂O₃ thin films, which was achieved by cooperative condensation/hydrolysis and thiol-ene click chemical reactions. The two-step synthetic approach consists of an initial silanization of the Al₂O₃ film with vinyltrimethoxysilane (VTMS), followed by a photo-promoted growth of surface-bound nanoparticles in the presence of (3-mercaptopropyl)trimethoxysilane (MPTMS). Characterization by means of FE-SEM, XPS and EDS points towards the growth of the nanohemispherical structures being governed by an initial nucleation of thiolated organosilica seeds in solution as a result of self-condensation of MPTMS and oxidation of thiols to disulfides. Once bound to the vinyl terminated Al₂O₃via photo-assisted thiol-ene coupling, these seeds promote area-selective growth of the nanoparticles through binding of further MPTMS from the solution. After an additional ALD deposition of ZnO, the resulting thin hybrid film exhibits enhanced hydrophobicity when compared to ZnO films deposited directly on Al₂O₃ under the same processing conditions.

Keywords: Al(2)O(3); Atomic layer deposition; Nanohemispheres; Organosilica hybrids; Thin films; Thiol-ene reaction; ZnO.