Study on photocatalytic performance of cerium-graphene oxide-titanium dioxide composite film for formaldehyde removal

Abstract

In order to degrade in‐car formaldehyde gas, graphene oxide (GO), cerium (Ce), and TiO2 were organically combined by one‐step sol–gel method. Then the mixed collosol was coated onto the surface of inorganic glass substrates to form Ce‐GO‐TiO2 composite film by way of immersion, coating, and calcinations. The morphology and crystal structure of as‐prepared Ce‐GO‐TiO2 film were studied by a series of detection techniques. The photocatalytic performance of this film was analyzed by the degradation effect of formaldehyde under simulated sunlight. The results showed that the Ce‐GO‐TiO2 film had the inbuilt mesoporous structure in the lamellar stacking with particles. When the doping amount of Ce and GO were 0.4 and 0.2% (mass ratio), the composite film can improve effectively the response to the visible light and its degradation rate for low concentration of formaldehyde was up to 83.8% in simulated sunlight for 7 h, which could be attributed to the co‐function of Ce and GO.

Photocatalytic Properties of Titanium Dioxide Thin Films Doped with Noble Metals (Ag, Au, Pd, and Pt)

“…The most promising photocatalyst is TiO 2 . TiO 2 in different types and forms has been extensively studied as a semiconductor for photocatalytic degradation of water organic pollutants, such as dyes, phenolic compounds, and for disinfecting wastewater . The great interest in the development of TiO 2 ‐mediated photocatalysis is due to the high chemical stability, non‐toxicity, and optical properties of this material .…”

“…For photocatalytic applications, TiO 2 may be used as a suspension in an aqueous solution or it may be immobilized onto a supporting substrate . Although the TiO 2 suspension systems are more efficient due to the larger surface‐to‐volume ratio, they require a post‐treatment step of nanoparticle filtration/separation, in order to remove the catalyst nanoparticles to avoid the loss of catalyst material and pollution of water.…”

Reduced Graphene Oxide–Titanium Dioxide Nanocomposites: Structural Characterization and Photocatalytic Degradation of Gaseous Formaldehyde

“…The peak separation of ≈5.7 eV indicates the presence of Ti in the form of Ti 4+ ions. [ 2 ] Similarly, the O 1s peak at 529.9 and 531.5 eV can be assigned to TiOTi and TiOC bonds, respectively (Figure 4g,h). Furthermore, the shape of TiOC peak indicates that both TiO 2 and rGO have formed a chemical bond during the solvothermal process.…”

“…Moreover, inhalation of a high concentration of HCHO can result in headache, edema, coughing, diarrhea, emotional disorder, skin diseases, and several other health hazards. [ 2 ] Therefore, HCHO is named as a carcinogen by the International Agency for Research on Cancer (June 2004), the National Toxicology Program (June 2011), and the World Health Organization. [ 3,4 ] Therefore, the removal of released HCHO is extremely important to create a safe working and living environment.…”

“…In recent years, the HCHO elimination has received considerable research interest due to its harm to human health and environment. [ 1–9 ] For instance, Li et al [ 2 ] have prepared the CeGOTiO 2 ternary composites using sol–gel method and demonstrated that the presence of Ce (0.4 wt%) and GO (0.2 wt%) led to the HCHO degradation of 83.8% under simulated sunlight for 7 h. However, the utilization of TiO 2 /rGO nanocomposite is mainly focused on water splitting, [ 11 ] degradation of dyes, such as rhodamine B [ 17 ] and methylene blue, [ 18 ] and treatment of organic solvents, such as formic acid and acetone. [ 14,15 ] In 2013, Huang et al [ 9 ] have synthesized TiO 2 /GR composites by the solvothermal method and utilized tetra‐butyl orthotitanate (TBOT) as a Ti source and expensive GR as a C source.…”