Controlled Nitrogen Doping and Film Colorimetrics in Porous TiO₂ Materials Using Plasma Processing

Abstract

Nitrogen doping of TiO(2) films (N:TiO(2)) has been shown to improve the visible-light sensitivity of TiO(2), thereby increasing the performance of both photovoltaic and photocatalytic devices. Inductively coupled rf plasmas containing a wide range of nitrogen precursors were used to create nitrogen-doped TiO(2) films. These treatments resulted in anatase-phased materials with as high as 34% nitrogen content. As monitored with high-resolution X-ray photoelectron spectroscopy spectra, the nitrogen binding environments within the films were controlled by varying the plasma processing conditions. XPS peak assignments for multiple N 1s binding environments were made based on high resolution Ti 2p and O 1s XPS spectra, Fourier transform infrared spectroscopy (FTIR) data, and literature N 1s XPS peak assignments. The N:TiO(2) films produced via plasma treatments displayed colors ranging from gray to brown to blue to black, paralleling the N/Ti ratios of the films. Three possible mechanisms to explain the color changes in these materials are presented.

Higher visible photocatalytic activities of nitrogen doped In2TiO5 sensitized by carbon nitride

“…The density of N from Ti-N in the powder samples was evaluated to be 2.2 at.%, therefore only a small amount of nitrogen is doped into In 2 TiO 5 . Similar phenomena about nitrogen dopant were also found in other reports [10,30].…”

N-doped Na2Ti6O13@TiO2 core–shell nanobelts with exposed {1 0 1} anatase facets and enhanced visible light photocatalytic performance

“…These two peaks are quite similar to those in TTO-6 and Na 2 Ti 3 O 7 , and thus, can be assigned to the octahedrally coordinated Ti. In addition, there shows no shoulder at lower binding energies which are classically attributed to Ti 3+ species due to oxygen vacancies, indicating the existence of only Ti 4+ in N-TTO-6-2 [50,51]. As shown in Fig.…”

Investigation of cation (Sn2+) and anion (N3−) substitution in favor of visible light photocatalytic activity in the layered perovskite K2La2Ti3O10

“…The broad band near 3400 cm −1 corresponds to the N-H stretching vibration. The peak noticed around 2150 cm −1 can be assigned to the N C O stretching or -N C N stretching [40]. The strong bands in the range 1200-1700 cm −1 are correlated to the skeletal stretching vibrations of the aromatic rings and can be taken as the finger print for the presence of CN polymers.…”