TY - JOUR

T1 - Effect of substrates on femtosecond laser pulse-induced reductive sintering of cobalt oxide nanoparticles

AU - Mizoshiri, Mizue

AU - Yoshidomi, Kyohei

AU - Darkhanbaatar, Namsrai

AU - Khairullina, Evgenia M.

AU - Tumkin, Ilya I.

N1 - Publisher Copyright: © 2021 by the authors. Li-censee MDPI, Basel, Switzerland.

PY - 2021/12/10

Y1 - 2021/12/10

N2 - Direct writing of cobalt/cobalt oxide composites has attracted attention for its potential use in catalysts and detectors in microsensors. In this study, cobalt-based composite patterns were selectively formed on glass, polyethylene naphthalate (PEN), and polyethylene terephthalate (PET) substrates via the femtosecond laser reductive sintering of Co3O4 nanoparticles in an ambient at-mosphere. A Co3O4 nanoparticle ink, including the nanoparticles, ethylene glycol as a reductant, and polyvinylpyrrolidone as a dispersant, was spin-coated onto the substrates. Near-infrared femto-second laser pulses were then focused and scanned across the ink films to form the patterns. The non-sintered nanoparticles were subsequently removed from the substrate. The resulting sintered patterns were found to be made up of Co/CoO composites on the glass substrates, utilizing various pulse energies and scanning speeds, and the Co/CoO/Co3O4 composites were fabricated on both the PEN and PET substrates. These results suggest that the polymer substrates with low thermal re-sistance react with the ink during the reductive sintering process and oxidize the patterns more easily compared with the patterns on the glass substrates. Such a direct writing technique of co-balt/cobalt oxide composites is useful for the spatially selective printing of catalysts and detectors in functional microsensors.

AB - Direct writing of cobalt/cobalt oxide composites has attracted attention for its potential use in catalysts and detectors in microsensors. In this study, cobalt-based composite patterns were selectively formed on glass, polyethylene naphthalate (PEN), and polyethylene terephthalate (PET) substrates via the femtosecond laser reductive sintering of Co3O4 nanoparticles in an ambient at-mosphere. A Co3O4 nanoparticle ink, including the nanoparticles, ethylene glycol as a reductant, and polyvinylpyrrolidone as a dispersant, was spin-coated onto the substrates. Near-infrared femto-second laser pulses were then focused and scanned across the ink films to form the patterns. The non-sintered nanoparticles were subsequently removed from the substrate. The resulting sintered patterns were found to be made up of Co/CoO composites on the glass substrates, utilizing various pulse energies and scanning speeds, and the Co/CoO/Co3O4 composites were fabricated on both the PEN and PET substrates. These results suggest that the polymer substrates with low thermal re-sistance react with the ink during the reductive sintering process and oxidize the patterns more easily compared with the patterns on the glass substrates. Such a direct writing technique of co-balt/cobalt oxide composites is useful for the spatially selective printing of catalysts and detectors in functional microsensors.

KW - CoO nanoparticle ink

KW - Cobalt/cobalt oxide composite

KW - Femtosecond laser reductive sintering

KW - Polymer substrate

KW - Printing

UR - http://www.scopus.com/inward/record.url?scp=85120819830&partnerID=8YFLogxK

U2 - 10.3390/nano11123356

DO - 10.3390/nano11123356

M3 - Article

AN - SCOPUS:85120819830

VL - 11

JO - Nanomaterials

JF - Nanomaterials

SN - 2079-4991

IS - 12

M1 - 3356

ER -