Synthesis of Coral-Like Tantalum Oxide Films via Anodization in Mixed Organic-Inorganic Electrolytes

Abstract

We report a simple method to fabricate nano-porous tantalum oxide films via anodization with Ta foils as the anode at room temperature. A mixture of ethylene glycol, phosphoric acid, NH4F and H2O was used as the electrolyte where the nano-porous tantalum oxide could be synthesized by anodizing a tantalum foil for 1 h at 20 V in a two–electrode configuration. The as-prepared porous film exhibited a continuous, uniform and coral-like morphology. The diameters of pores ranged from 30 nm to 50 nm. The pores interlaced each other and the depth was about 150 nm. After calcination, the as-synthesized amorphous tantalum oxide could be crystallized to the orthorhombic crystal system. As observed in photocatalytic experiments, the coral-like tantalum oxide exhibited a higher photocatalytic activity for the degradation of phenol than that with a compact surface morphology, and the elimination rate of phenol increased by 66.7%.

Facile development and structural investigations of HAp and HAp/Ta nanostructures: Photocatalytic activity against Turq blue GL dye

“…In addition, the preparation of HAp/Ta by using a non-aqueous solvent in an inert atmosphere (Ar atmosphere) helps in the formation of metallic Ta around the HAp core. This is because, as reported in literature [4,46], the addition of a small amount of water molecules leads to the formation of the oxide layer of Ta (Ta 2 O 5 ). In the present work, a non-aqueous solvent and inert atmosphere were used for preparing HAp/Ta and water was not used.…”

“…The need to develop a suitable catalyst/photocatalyst that is in the nanoscale and with nanostructure has increased owing to the promising applications of nanomaterials in the field of industrial manufacturing processes [1][2][3], water splitting for environmental protection such as wastewater treatment [4,5], and bio diesel production to fulfil the requirement for alternate fuels [6]. Different types of catalysts have been used in the aforementioned processes and fields to produce suitable materials and to ensure environmental safety.…”

“…However, the photocatalytic activity of pure HAp is significantly low [41]. The transition series element Tantalum (Ta) is widely used as a catalyst in various industrial processes such as the photodegradation of pollutants [4,15]. Combination of materials like HAp and Ta can degrade organic and inorganic pollutants (dyes) and can be used for environmental waste purification and also for the photocatalytic decomposition of biomaterials like proteins and lipids.…”

A Novel Packed-bed Electrocatalysis Reactor (PBECR) for Efficient Degradation of Organic Compounds

“…8). The figure depicts generation of the hydroxyphenol molecules and carboxide or conjugated double bond groups (e.g., hydroquinone, benzoquinone and maleic anhydride), which locates in 200 nm to 220 nm and 230 nm to 270 nm wavelength, [32][33][34] respectively, during the whole process of the PBER (³2.77 h) and the initial stage of the PBECR (³2.08 h). While the accumulation of benzoquinone which is more poisonous than phenol was not found in the PBECR process after reaction time of 2.08 h, indicating the TiO 2 is favorable to accelerate phenol decomposition that lowers power consumption and should naturally be considered as a "green" technology.…”

Preparation of TiO2/boron-doped diamond/Ta multilayer films and use as electrode materials for supercapacitors

“…About 40% of the world Ta production is used for capacitors [22] which contain a Ta anode sintered in vacuum with a fine Ta powder and an anodic oxide film of Ta employed as a dielectric. In addition, exceptional corrosion resistance, high melting points, good mechanical strength, and excellent biocompatibility make tantalum capacitors ideal for use in harsh conditions [23][24][25]. Nanostructured Ta possesses large surface area high specific charge, and redox activity except the advantage of Ta bulk [26] and has promising application potential in supercapacitor.…”