Yasni Novi Hendri, Robi Kurniawan, Kouichi Takase, Yudi Darma
One-dimensional ZnO exhibits high polarization but is considered to be non-ferroelectric. Here, we show ferroelectricity in carbon-doped ZnO nanocolumnars deposited using one-step DC-unbalanced magnetron sputtering. Doping carbon effectively increases its lattice strain and turns the ZnO nanocolumnars into a ferroelectric material. The existence of a reversible permanent electric dipole is found from the P–E hysteresis loop of the carbon-doped ZnO nanocolumnars, where the highest coercivity (11.1 kV/cm) originated from zinc vacancies and remnant polarization (4.7 μC/cm2) originated from oxygen vacancies. Moreover, the presence of carbon modified the optical bandgap of the system. Supporting the experimental results, the first-principle calculation shows that the increment of C concentration decreases bandgap contributed by C 2p. Furthermore, the existence of ferroelectricity in ZnO has the potential to bring out the multiferroic properties for developing next-generation ZnO-based storage devices. © 2021 Elsevier Ltd and Techna Group S.r.l.
Department of Physics, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Ganesha 10, Bandung, 40132, Indonesia; Department of Physics, Faculty of Mathematics and Natural Sciences, Universitas Negeri Malang, Jl. Semarang No.5, East Java, 65145, Indonesia; Department of Physics, College of Sciences and Technology, Nihon University, Chiyoda, Tokyo, 101-0062, Japan
