scholarly journals Synthesis of novel MgAl layered double oxide grafted TiO2 cuboids and their photocatalytic activity on CO2 reduction with water vapor

2015 ◽  
Vol 5 (6) ◽  
pp. 3288-3295 ◽  
Author(s):  
Cunyu Zhao ◽  
Lianjun Liu ◽  
Guiying Rao ◽  
Huilei Zhao ◽  
Luhui Wang ◽  
...  

Photocatalytic CO2 reduction with H2O by hybrid MgAl-LDO/TiO2 materials.

2020 ◽  
Vol 10 (9) ◽  
pp. 2893-2904 ◽  
Author(s):  
Ziyao Wan ◽  
Maocong Hu ◽  
Bingbing Hu ◽  
Tao Yan ◽  
Kang Wang ◽  
...  

A possible mechanism to explain the impact of La doping on electron transfer process in wide band gap semiconductor In(OH)3.


Author(s):  
Seremak Wioletta ◽  
Baszczuk Agnieszka ◽  
Jasiorski Marek ◽  
Gibas Anna ◽  
Winnicki Marcin

AbstractThis work shows that the titanium dioxide coatings obtained by low-pressure cold gas spraying with the use of the sol–gel amorphous TiO2 powder are characterized by photocatalytic activity despite their partial amorphous content. Moreover, the research outcome suggests that the decomposition rate of organic pollutants is enhanced after long-term exposure to moisture. The condensation humidity test is not detrimental to the continuity and integrity of the coating, but the phase composition of coatings changes—with the exposure to water vapor, the portion of the amorphous phase crystallizes into brookite. The mechanism responsible for the conversion of amorphous TiO2 into brookite is attributed to the water-driven dissolution and reprecipitation of TiO6 octahedra. It has been shown that an additional parameter necessary for the stabilization of the brookite is the oxygen depletion of the amorphous structure of titanium dioxide. Considering the results presented in this paper and the advantages of a portable, low-pressure cold spray system for industrial applications, it is expected that TiO2 coatings produced from a sol–gel feedstock powder can be further developed and tested as efficient photocatalysts.


2014 ◽  
Vol 14 (2) ◽  
pp. 122-130 ◽  
Author(s):  
Oman Zuas ◽  
Jin Seog Kim ◽  
Jarnuzi Gunlazuardi

In this report, the results from a study on the influence of operational parameters on TiO2 photocatalytic activity for CO2 reduction under an ultraviolet-visible (UV-vis) illumination are presented. The results indicated that the TiO2 was found to be active for CO2 reduction with CH3OH as the major products, while other minor products (CO, CH4, and C2H4) were also detected. In addition, the formation of such reduction products was obviously influenced by the operational parameters. Under this study, the optimum operational parameters for CO2 reduction at 298 °K were determined to be: NaOH concentration 0.2 M, TiO2 dosage 2 g/L, volume of the reaction media 75 mL, the pressure of system 800 kPa. It was also found that the increase in UV-vis illumination time have increased the yield of product formation. A possible reaction pathway for the formation of the reduction products is also discussed.


2020 ◽  
Vol 44 (39) ◽  
pp. 16795-16809 ◽  
Author(s):  
Zambaga Otgonbayar ◽  
Kwang Youn Cho ◽  
Won-Chun Oh

Effective charge transfer is a key factor in enhancing the catalytic activity of photocatalytic nanocomposite materials.


Catalysts ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 789
Author(s):  
Gang-Juan Lee ◽  
Yu-Hong Hou ◽  
Hsin-Ting Huang ◽  
Wenmin Wang ◽  
Cong Lyu ◽  
...  

A novel heterostructure consisting of Ru and Cu co-doped ZnS nanopowders (RCZS) into a MoS2-graphene hybrid (MSG) is successfully prepared by the microwave-assisted solvothermal approach. RCZS nanopowders are fabricated on the surface of MSG, which produces a nanoscale interfacial between RCZS and MSG. As the photo-excited electrons of RCZS can easily migrate to MoS2 through graphene by hindering the electron and hole (e– and h+) recombination, the photocatalytic activity could be improved by effective charge transfer. As RCZS are anchored onto the MSG, the photoluminescence intensity of the chalcogenide composite photocatalyst obviously decreases. In addition, a quaternary ruthenium and copper-based chalcogenide RCZS/MSG is able to improve the harvest and utilization of light. With the increase in the concentrations of Ru until 4 mol%, the band gap significantly decreases from 3.52 to 2.73 eV. At the same time, moderate modification by ruthenium can decrease the PL intensity compared to the pristine CZS/MSG sample, which indicates the enhancement of e– and h+ separation by Ru addition. The photocatalytic activity of as-synthesized chalcogenide composite photocatalysts is evaluated by the photocatalytic carbon dioxide reduction. Optimized operation conditions for carbon dioxide reduction have been performed, including the concentration of NaOH solution, the amount of RCZS/MSG photocatalyst, and the content of co-doped ruthenium. The doping of ruthenium would efficiently improve the performance of the photocatalytic activity for carbon dioxide reduction. The optimal conditions, such as the concentration of 2 M NaOH and the 0.5RCZS/MSG dosage of 0.05 g L–1, provide the maximum methane gas yield of 58.6 μmol h−1 g–1.


2020 ◽  
Vol 93 (5) ◽  
pp. 694-700 ◽  
Author(s):  
Ryota Ito ◽  
Masato Akatsuka ◽  
Akiyo Ozawa ◽  
Muneaki Yamamoto ◽  
Tetsuo Tanabe ◽  
...  

Molecules ◽  
2019 ◽  
Vol 24 (9) ◽  
pp. 1779 ◽  
Author(s):  
Asif Hayat ◽  
Mati Ur Rahman ◽  
Iltaf Khan ◽  
Javid Khan ◽  
Muhammad Sohail ◽  
...  

This work incorporates a variety of conjugated donor-acceptor (DA) co-monomers such as 2,6-diaminopurine (DP) into the structure of a polymeric carbon nitride (PCN) backbone using a unique nanostructure co-polymerization strategy and examines its photocatalytic activity performance in the field of photocatalytic CO2 reduction to CO and H2 under visible light irradiation. The as-synthesized samples were successfully analyzed using different characterization methods to explain their electronic and optical properties, crystal phase, microstructure, and their morphology that influenced the performance due to the interactions between the PCN and the DPco-monomer. Based on the density functional theory (DFT) calculation result, pure PCN and CNU-DP15.0 trimers (interpreted as incorporation of the co-monomer at two different positions) were extensively evaluated and exhibited remarkable structural optimization without the inclusion of any symmetry constraints (the non-modified sample derived from urea, named as CNU), and their optical and electronic properties were also manipulated to control occupation of their respective highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO). Also, co-polymerization of the donor–acceptor 2,6-diamino-purine co-monomer with PCN influenced the chemical affinities, polarities, and acid–base functions of the PCN, remarkably enhancing the photocatalytic activity for the production of CO and H2 from CO2 by 15.02-fold compared than that of the parental CNU, while also improving the selectivity.


Sign in / Sign up

Export Citation Format

Share Document