Roles of Vanadium and Nitrogen in Photocatalytic Activity of VN‐Codoped TiO₂ Photocatalyst

Abstract

In the present manuscript, we explore the VN-codoped TiO system intended to understand the role played by each dopant in synergistic enhancement in performance of TiO photocatalyst. The photocatalytic decomposition of organic pollutants in aqueous solution under visible light was used as a probe reaction to evaluate the performance of VN-codoped TiO samples with different V and N concentrations. An optical measurement of VN-codoped TiO shows considerable improved visible light absorption with increase in V-concentration as compared to increase in N concentration, which was due to the effective narrowing of the band gap by V-doping. The energy levels formed by N-dopants act as the trapping centers for photogenerated holes to suppress recombination process as indicated by PL and TRPL results. It is also observed that at high V-concentrations recombination centers are created in the form of oxygen vacancies as indicated by XPS and PL. In VN-codoped TiO , addition of N partially fills these oxygen vacancies to reduce the number of recombination centers and prolong the lifetime of charge carriers. Thus, V improves the visible light absorption while N reduces the recombination of electron-hole pairs, thus creating the synergistic effect to produce three times better performance than pure TiO .

Recent developments in layered double hydroxide structures with their role in promoting photocatalytic hydrogen production: A comprehensive review

“…This corresponds to the study carried out by Varma et al as they remarked that V doping on TiO 2 promotes the visible light absorption compared to the N-doping, effectively narrowing the band gap value up to 2.42 eV. 223 However, it was also highlighted that a substantial increase in the V concentration could result in the formation of the recombination centers by creating oxygen vacancies to form a deep level within the band gap, reducing the photocatalytic activity of the TiO 2 . On the other hand, incorporating 2% loading of V on ZnS is shown to offer an astounding hydrogen generation that is 17-fold higher than pure ZnS.…”

Synthesis of Nitrogen-doped KTaTeO6 with Enhanced Visible Light Photocatalytic Degradation of Methylene Blue

“…After being doped with nitrogen, the degradation efficiency reached to 92%, revealing that the photocatalytic performance was distinctly enhanced. Previous research studies have manifested that photocatalytic activity depends on many properties of the catalyst, including the bandgap energy, the surface structure, separation of photoinduced electron-hole pairs, extent of crystallinity, the surface adsorbed hydroxyl/ water species and nature of pollutant [29,67,68]. In the present work, the observed higher photocatalytic performance of the N-KTTO sample could be attributed to the several beneficial effects produced by the doping of N into the lattice of KTTO.…”

Water Challenges in South Asian Countries: A Focused Review on Emerging Nanomaterials and Technological Processes in Wastewater Treatment

“…Chakinala et al also reported enhancement in dye degradation by using bimetallic bismuth–silver-doped TiO 2 (Bi–Ag/TiO 2 ). Bi–Ag/TiO 2 showed 100% photodegradation of dye molecules attributed to the synergistic action of Bi and Ag on TiO 2 by charge separation, increased e-transfer, and high ability to absorb in the visible light range …”