The synthesis of nitrogen/sulfur co-doped TiO2 nanocrystals with a high specific surface area and a high percentage of {001} facets and their enhanced visible-light photocatalytic performance

Abstract

Nitrogen/sulfur co-doped anatase TiO2 nanocrystals with a high specific surface area and a high percentage of {001} facets were synthesized by a solvent-thermal process followed by the calcination with thiourea at an optimum heat treatment temperature. Under current experimental conditions, the optimum heat treatment temperature was found at 300°C, which successfully introduced nitrogen and sulfur dopants into the anatase lattice to replace a small portion of oxygen atoms while preserving the geometry of these anatase TiO2 nanocrystals to maintain a high percentage of {001} facets. These nitrogen/sulfur co-doped anatase TiO2 nanocrystals demonstrated a largely enhanced light absorption in the whole visible-light range and exhibited much higher photocatalytic performance than both P25 TiO2 nanoparticles and anatase TiO2 nanocrystals with a high percentage of {001} facets under visible-light illumination.

Photocatalytic Treatment of An Actual Confectionery Wastewater Using Ag/TiO2/Fe2O3: Optimization of Photocatalytic Reactions Using Surface Response Methodology

“…Advanced oxidation processes (AOPs) are promising and environmentally friendly wastewater treatment technologies capable of mineralizing deleterious substances in wastewater systems [4,[8][9][10]. Among all, photocatalysis, especially with titanium dioxide (TiO 2 ), is commonly studied owing to its high chemical stability, promising efficiency, low cost, and non-toxicity [10][11][12]. The study conducted by Sang et al showed promising efficiency of TiO 2 in degrading the artificial sweeteners found in confectionery wastewater and in mineralizing the intermediate products generated during the degradation process [4].…”

“…However, the application of TiO 2 is limited by the ultraviolet (UV) activation and the fast recombination rate of the generated electron-hole pairs [10,12,14]. Hence, modifications of TiO 2 photocatalysts through metal doping, non-metal doping, and its combination with another semiconductor photocatalyst are common methods to extend the absorption wavelength of TiO 2 towards visible light spectrum, to restrict the recombination of electron-hole pairs, and to increase the specific surface area of the photocatalyst [9][10][11][12][13][14][15][16][17].…”

The selective deposition of silver nanoparticles onto {1 0 1} facets of TiO 2 nanocrystals with co-exposed {0 0 1}/{1 0 1} facets, and their enhanced photocatalytic reduction of aqueous nitrate under simulated solar illumination

“…Recently, anatase TiO 2 nanocrystals with exposed facets were developed, which demonstrated enhanced photocatalytic performance than their counterparts in the micrometer size range due to their largely increased surface areas [14][15][16][17][18]. It was found that the photocatalytic activity of anatase TiO 2 could be further modulated by incorporating different exposed crystal facets [19][20][21][22].…”

Co‐doping Nitrogen/Sulfur through a Solid‐State Reaction to Enhance the Electrochemical Performance of Anatase TiO2 Nanoparticles as a Sodium‐Ion Battery Anode

“…Due to the partial overlapping of S 2 p 3/2 and S 2 p 1/2 , XPS signals associated with the substituted sulfur ( S sub ) should be found in the 159.8 eV–165.4 eV range (peak I) . The peak around 169 eV (peak II) corresponds to the S species adsorbed on the N/S‐TiO 2 ,…”