Stojadinović Stevan, Radić Nenad, Vasilić Rastko
Faculty of Physics, University of Belgrade, Studentski trg 12-16, 11000 Belgrade, Serbia.
Faculty of Forestry, University of Belgrade, Kneza Višeslava 1, 11000 Belgrade, Serbia.
Micromachines (Basel). 2023 Mar 22;14(3):701. doi: 10.3390/mi14030701.
TaO coatings were created using micro-arc discharges (MDs) during anodization on a tantalum substrate in a sodium phosphate electrolyte (10 g/L NaPO·10HO). During the process, the size of MDs increases while the number of MDs decreases. The elements and their ionization states present in MDs were identified using optical emission spectroscopy. The hydrogen Balmer line H shape analysis revealed the presence of two types of MDs, with estimated electron number densities of around 1.1 × 10 m and 7.3 × 10 m. The effect of MDs duration on surface morphology, phase and chemical composition, optical absorption, and photoluminescent, properties of TaO coatings, as well as their applications in photocatalytic degradation of methyl orange, were investigated. The created coatings were crystalline and were primarily composed of TaO orthorhombic phase. Since TaO coatings feature strong absorption in the ultraviolet light region below 320 nm, their photocatalytic activity is very high and increases with the time of the MDs process. This was associated with an increase of oxygen vacancy defects in coatings formed during the MDs, which was confirmed by photoluminescent measurements. The photocatalytic activity after 8 h of irradiation was around 69%, 74%, 80%, and 88% for TaO coatings created after 3 min, 5 min, 10 min, and 15 min, respectively.
通过在磷酸钠电解液（10 g/L NaPO·10HO）中对钽基底进行阳极氧化时利用微弧放电（MDs）来制备TaO涂层。在此过程中，微弧放电的尺寸增大而数量减少。利用发射光谱法确定了微弧放电中存在的元素及其电离态。氢巴尔末线H形状分析揭示存在两种类型的微弧放电，估计电子数密度分别约为1.1×10 m和7.3×10 m。研究了微弧放电持续时间对TaO涂层的表面形貌、相结构和化学成分、光吸收以及光致发光性能的影响，以及它们在甲基橙光催化降解中的应用。所制备的涂层为晶体，主要由TaO正交相组成。由于TaO涂层在320 nm以下的紫外光区域具有强吸收，其光催化活性非常高，并且随着微弧放电过程的时间增加而提高。这与微弧放电过程中形成的涂层中氧空位缺陷的增加有关，这通过光致发光测量得到证实。对于分别在3分钟、5分钟、10分钟和15分钟后制备的TaO涂层，辐照8小时后的光催化活性分别约为69%、74%、80%和88%。
