Effects of Pulsed Negative Bias and Current Density on Properties of N-doped TiO_2 Films Deposited by Arc Son Plating

摘要

The N-doped TiO_2 thin films of different pulsed negative bias and different current density were deposited on medical glass slide by arc ion plating. The influence of pulsed substrate bias and arc current on film properties was investigated by varying pulsed negative biases from 0 V to-600V and arc current from 40A to 60A. Film structure, surface morphologies and optical properties were measured with XRD, SEM and UV-VIS transmittance spectroscope. Photo-catalytic performance of the films was evaluated by degrading methyl orange. The results show that the N-doped TiO_2 films absorption edges successfully move to 550nm and the films have better visible light response. Applying the negative pulse bias extends the absorption edge 5 nm - 40 nm, the absorption edges shift towards the visible region with increasing arc current. The annealing treatment has a great impact on extending the absorption edge of the lower arc current, and the best extending can increase 64nm after annealing. The as-deposited film surface roughness decreases with the pulsed negative bias increasing, the film surface grain size increases significantly after annealing. The N dope not only reduces TiO_2 films UV catalytic performance, but also extends its catalytic properties to the sun light.