Efficient photocatalytic degradation of 4‐nitrophenol over graphene modified TiO₂

Abstract

BACKGROUND: Photocatalytic degradation of organic compounds, including nitrophenol, is one of the most popular approaches to pollution control and disposal. Graphene-based nanocomposites have attracted considerable attention in photocatalytic research owing to their excellent electrical, thermal and mechanical properties. In this work, TiO 2 material was modified with graphene by a hydrothermal method, the photocatalytic performance of the prepared catalyst was evaluated by degradation of 4-nitrophenol, which is a highly toxic, stable and carcinogenic organic pollutant. RESULTS:The characterization results showed that the low amount of graphene disperses well over TiO 2 and it does not influence the crystal phase, but makes the specific surface area of graphene/TiO 2 greater than that of TiO 2 . Compared with TiO 2 , graphene/TiO 2 exhibits enhanced photocatalytic activity for the degradation of 4-nitrophenol under simulated solar irradiation. CONCLUSION:The enhanced activity of photo-degradation could be attributed to the involved graphene being beneficial to charge transportation and separation of photogenerated charge carriers, and providing more surface active sites for degradation reaction of the target pollutant. The present result highlights the important application of graphene as a novel carbon material in treating highly toxic pollutant through photocatalysis technology.

Photocatalytic and photosensitization reactions of surface modified W6+ and N3‒ doped TiO2 with curcumin/potassium curcuminate molecules

“…This model pollutant was chosen since it was found to be highly stable in aqueous media due to the substituted electron withdrawing -NO 2 group along with electron donating -OH group. The literature also shows similar results and the time duration taken for degradation was found to be quite high [11][12][13].…”

Visible-light-driven H2production and decomposition of 4-nitrophenol over nickel phosphides

“…Samples were taken out every 60 min, and centrifuged at speed of 10 000 rpm for 10 min in order to remove the photocatalysts, the obtained clear solution was analyzed using spectrophotometric method on a 7SS2 spectrophotometer (made in Shanghai, China), and the absorbance was measured at the wavelength of 315 nm. 34 …”

Graphene decorated MoS2for eosin Y-sensitized hydrogen evolution from water under visible light

“…Graphene oxide (denoted as GO) was synthesized by the modied Hummers method according to our previous work. 42 In a typical process, natural graphite (1.0 g) and NaNO 3 (0.50 g) were mixed with 23 mL of concentrated H 2 SO 4 (98%) in an ice bath (#4 C), and the mixture was stirred for 20 min, then 6.0 g of KMnO 4 was added within 60 min. The reaction system was kept at room temperature for 2 h, subsequently the suspension was rapidly heated to 95 C and kept for 30 min, aer that, the cold mixture (#1 C) of distilled water (100 mL) and H 2 O 2 (10 mL) was added and the system immediately became yellow-brown, the resulting mixture was ltrated and washed with distilled water and absolute ethanol until the ltrate is neutral and no SO 4 2À (determined with saturated BaCl 2 solution) in it.…”