Tuneable conductivity at extreme electric fields in ZnO tetrapod-silicone composites for high-voltage power cable insulation
Artikel i vetenskaplig tidskrift, 2022
Resistive Field Grading Materials (RFGM) are used in critical regions in the electrical insulation system of high-voltage direct-current cable systems. Here, we describe a novel type of RFGM, based on a percolated network of zinc oxide (ZnO) tetrapods in a rubber matrix. The electrical conductivity of the composite increases by a factor of 108 for electric fields > 1 kV mm-1, as a result of the highly anisotropic shape of the tetrapods and their significant bandgap (3.37 eV). We demonstrate that charge transport at fields < 1 kV mm-1 is dominated by thermally activated hopping of charge carriers across spatially, as well as energetically, localized states at the ZnO-polymer interface. At higher electric fields (> 1 kV mm-1) band transport in the semiconductive tetrapods triggers a large increase in conductivity. These geometrically enhanced ZnO semiconductors outperform standard additives such as SiC particles and ZnO micro varistors, providing a new class of additives to achieve variable conductivity in high-voltage cable system applications.
Författare
Helena Greijer
Hitachi, Ltd.
Nicola Mirotta
Istituto per la Sintesi Organica e la Fotoreattività (ISOF-CNR)
E. Treossi
Istituto per la Sintesi Organica e la Fotoreattività (ISOF-CNR)
Filippo Valorosi
Istituto per la Sintesi Organica e la Fotoreattività (ISOF-CNR)
Fabian Schütt
Christian-Albrechts-Universität zu Kiel
Leonard Siebert
Christian-Albrechts-Universität zu Kiel
Yogendra Kumar Mishra
Syddansk Universitet
Rainer Adelung
Christian-Albrechts-Universität zu Kiel
Vincenzo Palermo
Istituto per la Sintesi Organica e la Fotoreattività (ISOF-CNR)
Chalmers, Industri- och materialvetenskap, Material och tillverkning
Henrik Hillborg
Hitachi, Ltd.
Scientific Reports
2045-2322 (ISSN) 20452322 (eISSN)
Vol. 12 1 6035-Ämneskategorier
Materialkemi
Annan elektroteknik och elektronik
Den kondenserade materiens fysik
DOI
10.1038/s41598-022-09966-4
PubMed
35410428