Tippo Posak, Thongsuwan Wiradej, Wiranwetchayan Orawan, Kumpika Tewasin, Kantarak Ekkapong, Singjai Pisith
Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai, 50200, Thailand.
Graduate School, Chiang Mai University, Chiang Mai, 50200, Thailand.
Sci Rep. 2020 Sep 24;10(1):15690. doi: 10.1038/s41598-020-72883-x.
Nickel oxide (NiO) films cover numerous electronic applications, including transparent conducting oxides and hole transport layer, because of its high transparency and wide band gap. A sparking discharge is a new and unique method for the deposition of NiO films due to non-complex operation and non-requirement of a vacuum atmosphere. Unfortunately, NiO films by the sparking method display a porous surface with inferior crystallinity. By assisting a uniform magnetic field in the sparking method, the porous and the crystallinity of NiO are improved. However, electrical properties of the NiO films deposited by this strategy are poor. In order to improve the electrical properties of NiO, a substitutional of Ni ions by Co ions is considered. In this study, we report an influence of Co concentration on properties of NiO films by sparking under a uniform magnetic field. Our results indicate that an increase in Co concentration to 0.1 M improves the crystallinity and increases a carrier concentration of NiO, resulting in a reduction of the resistivity. This consequence is in agreement with the increase in a number of higher-valence Ni because of the Co substituted Ni. Based on our research, Co-NiO film is promising materials for a transparent conductor.
氧化镍（NiO）薄膜因其高透明度和宽带隙而覆盖了众多电子应用，包括透明导电氧化物和空穴传输层。火花放电是一种沉积NiO薄膜的新颖独特方法，因为其操作不复杂且无需真空环境。不幸的是，通过火花法制备的NiO薄膜呈现出多孔表面且结晶度较差。在火花法中辅助施加均匀磁场，可改善NiO的多孔性和结晶度。然而，通过这种策略沉积的NiO薄膜的电学性能较差。为了改善NiO的电学性能，考虑用Co离子替代Ni离子。在本研究中，我们报道了在均匀磁场下通过火花放电时Co浓度对NiO薄膜性能的影响。我们的结果表明，将Co浓度提高到0.1 M可改善结晶度并增加NiO的载流子浓度，从而降低电阻率。这一结果与由于Co替代Ni而导致的高价Ni数量增加相一致。基于我们的研究，Co-NiO薄膜是一种很有前途的透明导体材料。
