One‐Step Plasma Synthesis of Nb₂O₅ Nanofibers and their Enhanced Photocatalytic activity

Abstract

Fiberform nanostructured niobium (Nb) was fabricated by one step helium (He) plasma irradiation. He ion implantation formed He nano-bubbles on a Nb plate and led to formation of protrusions while migrating in Nb matrix; fiberform nanostructures (FN) were grown when the fluence became high (> 10 26 m À2 ). The necessary conditions for the formation of Nb FN were revealed to be the surface temperature range of 900-1100 K and the incident ion energy higher than 70 eV. The sample was oxidized at 573-773 K in an air atmosphere, and Pt nanoparticles were photo-deposited on the Nb 2 O 5 samples. The surface was analyzed by scanning electron microscope, transmission electron microscope, x-ray photoelectron spectroscopy, and ultraviolet-visible spectrophotometry. Photocatalytic activity of the fabricated materials was studied using methylene blue (MB) decolorization process. An enhanced photocatalytic performance was identified on FN Nb 2 O 5 substrate with Pt deposition.[a] Dr.

Photocatalytic decomposition of ethylene using He plasma induced nano-TiO2

“…18) Although formation mechanism has yet to be fully understood, it is recognized that formed He nanobubbles by He ion bombardment play important roles for the growth of fiberform nanostructures. 19) Photocatalytic activity of He plasma induced nanostructures have been investigated on (partially) oxidized W, [20][21][22][23] vanadium, 24) niobium, 25) iron 26) and Ti. 27) In this study, we use He plasmas to induce morphology changes in micro-and nano-meter scales, and photocatalytic performance of those fabricated materials to degrade ethylene is measured.…”

Growth of nano-fibers on HCP-metals by He plasma irradiation

“…The shear modulus and melting point of Zr were in between those of Co and Hf. Following the categorization of the He-induced FN growth in terms of T m and G, as discussed in, 17) Re is categorized to the metal on which FNs can be easily formed, while Co, Zr, and Hf can be categorized to the metals on which thin FN layers are grown. It is noted that G of Zr and Hf is lower than that of Nb, which has the lowest shear modulus in Table I.…”

“…The FN growth was identified on various metals that have body centered cubic (BCC) crystal structures such as W, face centered cubic (FCC), and hexagonal close packing (HCP) crystal structures; Table I summarizes metals on which the growth of FNs was identified, as was discussed in Refs. [14][15][16][17]. The He-plasma-induced FN growth was clearly observed on twelve metals as far as we know: six of them [W, molybdenum (Mo), iron (Fe), tantalum (Ta), vanadium (V), and niobium (Nb)] have BCC crystal structure, four of them [iridium (Ir), rhodium (Rh), nickel (Ni), and platinum (Pt)] have FCC crystal structure, and two of them [rhenium (Re) and ruthenium (Ru)] have HCP crystal structure.…”