Cr, Fe - Doped Anatase TiO2 Photocatalyst: DFT+U Investigation on Band Gap

Ginting, Listra Yehezkiel; Agusta, Mohammad Kemal; Nugraha, Nugraha; Lubis, Ahmad Husin; Dipojono, Hermawan Kresno

doi:10.4028/www.scientific.net/amr.893.31

Cited by 4 publications

(3 citation statements)

References 26 publications

(25 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Considering the XPS result discussed above, the introduction of new intermediate levels at the nanoparticles’ surface may be a likely explanation for the emergence of this new absorption band. These levels can act as traps and reduce the rate of recombination [ 82 , 101 ]. Besides that, a further reduction of the nanoparticles’ size could accentuate their contribution from surface defects, due to the increase in the surface/volume ratio.…”

Section: Resultsmentioning

confidence: 99%

Enhanced Fe-TiO2 Solar Photocatalysts on Porous Platforms for Water Purification

et al. 2022

View full text Add to dashboard Cite

In this study, polyethylene glycol-modified titanium dioxide (PEG-modified TiO2) nanopowders were prepared using a fast solvothermal method under microwave irradiation, and without any further calcination processes. These nanopowders were further impregnated on porous polymeric platforms by drop-casting. The effect of adding iron with different molar ratios (1, 2, and 5%) of iron precursor was investigated. The characterization of the produced materials was carried out by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and Raman spectroscopy. Optical characterization of all the materials was also carried out. SEM showed that pure TiO2 and Fe-TiO2 nanostructures presented similar nanosized and spherical particles, which uniformly covered the substrates. From XRD, pure TiO2 anatase was obtained for all nanopowders produced, which was further confirmed by Raman spectroscopy on the impregnated substrates. XPS and UV–VIS absorption spectroscopy emission spectra revealed that the presence of Fe ions on the Fe-TiO2 nanostructures led to the introduction of new intermediate energy levels, as well as defects that contributed to an enhancement in the photocatalytic performance. The photocatalytic results under solar radiation demonstrated increased photocatalytic activity in the presence of the 5% Fe-TiO2 nanostructures (Rhodamine B degradation of 85% after 3.5 h, compared to 74% with pure TiO2 for the same exposure time). The photodegradation rate of RhB dye with the Fe-TiO2 substrate was 1.5-times faster than pure TiO2. Reusability tests were also performed. The approach developed in this work originated novel functionalized photocatalytic platforms, which were revealed to be promising for the removal of organic dyes from wastewater.

show abstract

Section: Resultsmentioning

confidence: 99%

Enhanced Fe-TiO2 Solar Photocatalysts on Porous Platforms for Water Purification

et al. 2022

View full text Add to dashboard Cite

show abstract

“…The Fe 3+ ion can become the trapping site of photoinduced electrons because of the reducibility of these electrons, thereby reducing Fe 3+ to Fe 2+ . Fe 2+ ions then become the trapping site of holes, as holes feature oxidizability [ 10 ]. These findings suggest that N and Fe codoping of AC/TiO 2 exerts a synergistic effect on reducing the band gap.…”

Section: Discussionmentioning

confidence: 99%

Microwave-Assisted Synthesis of Carbon-Based (N, Fe)-Codoped TiO2 for the Photocatalytic Degradation of Formaldehyde

Tian¹,

Wu²,

Tong³

et al. 2015

Nanoscale Res Lett

View full text Add to dashboard Cite

A microwave-assisted sol–gel method was used to synthesize (N, Fe)-codoped activated carbon (AC)/TiO2 photocatalyst for enhanced optical absorption in the visible light region. The prepared samples were characterized via X-ray diffraction, scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, Brunauer–Emmett–Teller analysis, ultraviolet–visible light spectroscopy, X-ray photoelectron spectroscopy, and photoluminescence spectroscopy. The results showed no significant difference in the surface area of AC/TiO2 (approximately 500 m2/g) after doping. TiO2 was uniformly distributed on the surface of AC, which exhibited coexisting anatase and rutile structures with a mean crystallite diameter of approximately 20 nm. N and Fe monodoping on AC/TiO2 reduced the energy band gap of TiO2 to 2.81 and 2.79 eV, respectively, which mainly attributed to the impurity energy formed in the energy gap of TiO2. In (N, Fe)-codoped AC/TiO2, N and Fe are incorporated into the TiO2 framework and narrow the band gap of TiO2 to 2.58 eV, thereby causing a large redshift. Codoping of N and Fe enhanced the production of hydroxyl radicals (⋅OH) and improved the photocatalytic activity of the resultant AC/TiO2 compared with those of undoped and N- or Fe-monodoped AC/TiO2. N-Fe-AC/TiO2 degraded 93 % of the formaldehyde under Xe-lamp irradiation. Moreover, the photocatalyst was easily recyclable. In summary, a novel and efficient method to mineralize low concentrations of HCHO in wastewater was discovered.

show abstract

“…Therefore, it is important to improve the photocatalytic performance of TiO 2 by improving its internal structure. Metal or nonmetal doping of TiO 2 could extend its optical absorption range into the visible light region and modify the generation rate of the electron-hole pairs [9][10][11][12]. TiO 2 doped with transition metals has recently been prepared, and studies on these materials have shown that the energy band gap of TiO 2 decreases with decreasing recombination rate of photogenerated electron-hole pairs [13][14][15].…”

Section: Introductionmentioning

confidence: 99%

Microwave-Assisted Synthesis of Carbon-Based (N, Fe)-Codoped TiO2 for the Photocatalytic Degradation of Formaldehyde

Tian¹,

Wu²,

Tong³

et al. 2016

Nano Online

View full text Add to dashboard Cite

A microwave-assisted sol-gel method was used to synthesize (N, Fe)-codoped activated carbon (AC)/TiO 2 photocatalyst for enhanced optical absorption in the visible light region. The prepared samples were characterized via X-ray diffraction, scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, Brunauer-Emmett-Teller analysis, ultraviolet-visible light spectroscopy, X-ray photoelectron spectroscopy, and photoluminescence spectroscopy. The results showed no significant difference in the surface area of AC/TiO 2 (approximately 500 m 2 /g) after doping. TiO 2 was uniformly distributed on the surface of AC, which exhibited coexisting anatase and rutile structures with a mean crystallite diameter of approximately 20 nm. N and Fe monodoping on AC/TiO 2 reduced the energy band gap of TiO 2 to 2.81 and 2.79 eV, respectively, which mainly attributed to the impurity energy formed in the energy gap of TiO 2 . In (N, Fe)-codoped AC/TiO 2 , N and Fe are incorporated into the TiO 2 framework and narrow the band gap of TiO 2 to 2.58 eV, thereby causing a large redshift. Codoping of N and Fe enhanced the production of hydroxyl radicals (⋅OH) and improved the photocatalytic activity of the resultant AC/TiO 2 compared with those of undoped and N-or Femonodoped AC/TiO 2 . N-Fe-AC/TiO 2 degraded 93 % of the formaldehyde under Xe-lamp irradiation. Moreover, the photocatalyst was easily recyclable. In summary, a novel and efficient method to mineralize low concentrations of HCHO in wastewater was discovered.

show abstract

Cr, Fe - Doped Anatase TiO2 Photocatalyst: DFT+U Investigation on Band Gap

Cited by 4 publications

References 26 publications

Enhanced Fe-TiO2 Solar Photocatalysts on Porous Platforms for Water Purification

Enhanced Fe-TiO2 Solar Photocatalysts on Porous Platforms for Water Purification

Microwave-Assisted Synthesis of Carbon-Based (N, Fe)-Codoped TiO2 for the Photocatalytic Degradation of Formaldehyde

Microwave-Assisted Synthesis of Carbon-Based (N, Fe)-Codoped TiO2 for the Photocatalytic Degradation of Formaldehyde

Contact Info

Product

Resources

About