Search

Your search keyword '"Tu Ngoc Lam"' showing total 2 results
Start Over Author "Tu Ngoc Lam" Journal micromachines
2 results on '"Tu Ngoc Lam"'

1. Enhanced Photocatalytic Performance of Nitrogen-Doped TiO2 Nanotube Arrays Using a Simple Annealing Process

Author

Phuoc Huu Le, Le Trung Hieu, Tu-Ngoc Lam, Nguyen Thi Nhat Hang, Nguyen Van Truong, Le Thi Cam Tuyen, Pham Thanh Phong, and Jihperng Leu

Subjects
N-doped TNAs, two-step anodization, photocatalytic activity, thermal annealing, modified TiO2, band gap, Mechanical engineering and machinery, TJ1-1570
Abstract

Nitrogen-doped TiO2 nanotube arrays (N-TNAs) were successfully fabricated by a simple thermal annealing process in ambient N2 gas at 450 °C for 3 h. TNAs with modified morphologies were prepared by a two-step anodization using an aqueous NH4F/ethylene glycol solution. The N-doping concentration (0–9.47 at %) can be varied by controlling N2 gas flow rates between 0 and 500 cc/min during the annealing process. Photocatalytic performance of as-prepared TNAs and N-TNAs was studied by monitoring the methylene blue degradation under visible light (λ ≥ 400 nm) illumination at 120 mW·cm−2. N-TNAs exhibited appreciably enhanced photocatalytic activity as compared to TNAs. The reaction rate constant for N-TNAs (9.47 at % N) reached 0.26 h−1, which was a 125% improvement over that of TNAs (0.115 h−1). The significant enhanced photocatalytic activity of N-TNAs over TNAs is attributed to the synergistic effects of (1) a reduced band gap associated with the introduction of N-doping states to serve as carrier reservoir, and (2) a reduced electron‒hole recombination rate.

Published
2018
Full Text
View/download PDF

2. Enhanced Photocatalytic Performance of Nitrogen-Doped TiO2 Nanotube Arrays Using a Simple Annealing Process

Author

Nguyen Thi Nhat Hang, Le Trung Hieu, Tu Ngoc Lam, Nguyen Van Truong, Pham Thanh Phong, Phuoc Huu Le, Le Thi Cam Tuyen, and Jihperng Leu

Subjects
thermal annealing, photocatalytic activity, Materials science, Annealing (metallurgy), Band gap, lcsh:Mechanical engineering and machinery, two-step anodization, Physics::Optics, 02 engineering and technology, 010402 general chemistry, 01 natural sciences, Condensed Matter::Materials Science, chemistry.chemical_compound, Reaction rate constant, band gap, modified TiO2, lcsh:TJ1-1570, N-doped TNAs, Electrical and Electronic Engineering, Aqueous solution, Anodizing, Mechanical Engineering, 021001 nanoscience & nanotechnology, 0104 chemical sciences, chemistry, Chemical engineering, Control and Systems Engineering, Photocatalysis, 0210 nano-technology, Ethylene glycol, Visible spectrum
Abstract

Nitrogen-doped TiO2 nanotube arrays (N-TNAs) were successfully fabricated by a simple thermal annealing process in ambient N2 gas at 450 &deg, C for 3 h. TNAs with modified morphologies were prepared by a two-step anodization using an aqueous NH4F/ethylene glycol solution. The N-doping concentration (0&ndash, 9.47 at %) can be varied by controlling N2 gas flow rates between 0 and 500 cc/min during the annealing process. Photocatalytic performance of as-prepared TNAs and N-TNAs was studied by monitoring the methylene blue degradation under visible light (&lambda, &ge, 400 nm) illumination at 120 mW&middot, cm&minus, 2. N-TNAs exhibited appreciably enhanced photocatalytic activity as compared to TNAs. The reaction rate constant for N-TNAs (9.47 at % N) reached 0.26 h&minus, 1, which was a 125% improvement over that of TNAs (0.115 h&minus, 1). The significant enhanced photocatalytic activity of N-TNAs over TNAs is attributed to the synergistic effects of (1) a reduced band gap associated with the introduction of N-doping states to serve as carrier reservoir, and (2) a reduced electron‒hole recombination rate.

Published
2018
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results