Development of g-C3N4-TiO2 visible active hybrid photocatalyst for the photodegradation of methyl orange

Abstract

In this paper, we report the synthesis of g-C 3 N 4 -TiO 2 hybrid photocatalyst by using the simple, cost-effective and eco-friendly process. The development of TiO 2 nanoflakes on the surface of g-C 3 N 4 nanosheet was carried out by the in situ sol-gel method. The XRD patterns reveal the anatase phase of TiO 2 in the g-C 3 N 4 -TiO 2 nanocomposite. HR-TEM images confirm the size of the nanoflakes in the range of 15-25 nm. The O-Ti and Ti-O-Ti bridge produces the absorption band from 560 to 710 cm −1 for TiO 2 ; it is due to stretching vibrations and the specific band at 805 cm −1 marks the sym-triazine ring of g-C 3 N 4 . UV-Vis spectra show a redshift from 394 to 471 nm in the nanocomposite concerning a decrease in band gap. From BET, it is seen that the surface area of bare TiO 2 and g-C 3 N 4 -TiO 2 are 66 and 146 m 2 g −1 , respectively. The nanoflakes morphology of g-C 3 N 4 -TiO 2 was confirmed from FE-SEM images. The EDS spectrum confirms C, N, Ti, and O elements which prove the purity of the nanocomposite. The g-C 3 N 4 -TiO 2 (1:4) acquired a noticeable enhancement of photocatalytic activity which is double for methyl orange degradation than TiO 2 .

Microwave Synthesis of Visible-Light-Activated g-C3N4/TiO2 Photocatalysts

“…To investigate the main active species involved in the photocatalytic degradation of MO, several reactive oxygen species (ROS) scavengers were added to the methyl orange solution prior to the addition of the catalyst. To evaluate the role of these species, ethylene diamine tetra acetic acid (EDTA, C 10 H 16 N 2 O 8 , ≥98% purity from Sigma-Aldrich, CAS: 60-00-4), isopropanol (IPA, C 3 H 8 O, 99.8% purity from Sigma-Aldrich) and p -benzoquinone (BQ, C 6 H 4 O 2 , ≥98% purity from Midland Scientific (Sigma-Aldrich), CAS: 106-51-4) were used, respectively, as hole scavengers (h + ), hydroxyl radical scavengers (·OH) and superoxide radical scavengers (·O 2 − ) [ 21 , 77 ]. The trapping experiments were conducted under the same conditions as those to evaluate the photocatalytic performance, additionally including 5 mL of a 0.5 mM aqueous solution of each scavenger [ 78 ].…”

“…Lately, a lot of attention has been paid to semiconductors with visible-light absorption as photocatalysts due to the abundance of visible light on the solar spectrum [ 16 , 21 , 22 , 23 , 24 ]. Although titanium dioxide (TiO 2 ) is a widely employed semiconductor in photocatalysis owing to its low toxicity, reduced cost and excellent photochemical stability [ 25 ], it mainly absorbs in the UV region [ 22 ], limiting its use in photocatalytic applications [ 16 ].…”

“…Several techniques have already been studied to improve the photocatalytic performance of TiO 2 under visible light, such as doping with metals [ 33 ]/non-metals [ 34 ], modification of surface defects [ 35 ] and the fabrication of heterostructures [ 21 , 36 ]. Among them, the formation of an enhanced heterostructure was proved not only to suppress the photogenerated charge carriers’ recombination rate but also to extend visible-light absorption, thereby improving the photocatalytic activity under visible light [ 21 , 37 ]. One material, which has started to be used to produce visible-light-activated photocatalysts based on heterostructures with TiO 2 , is graphitic carbon nitride [ 27 , 38 , 39 ].…”

g-C3N4 Based Photocatalyst for the Efficient Photodegradation of Toxic Methyl Orange Dye: Recent Modifications and Future Perspectives

“…The ZnO/Fe 3 O 4 /g-C 3 N 4 -50% composite exhibited a higher photocatalytic activity after five recycles [ 82 ]. Some g-C 3 N 4 composites reported for the efficient PD of MO dye are AgBr:g-C 3 N 4 [ 83 ], g-C 3 N 4 /TNTs heterojunctions [ 84 ], ternary g-C 3 N 4 /ZnO–W/M nanocomposites [ 85 ], g-C 3 N 4 -TiO 2 nanocomposite [ 86 ], CdS/g-C 3 N 4 hybrid nano-photocatalysts [ 87 ], MoO 3 –g-C 3 N 4 composites [ 88 ], g-C 3 N 4 /ZnO composites [ 89 ], CoFe 2 O 4 /g-C 3 N 4 nanocomposites [ 90 ], g-C 3 N 4 /Bi 4 O 5 I 2 [ 91 ], ternary g-C 3 N 4 /Ag/γ-FeOOH photocatalysts [ 92 ], etc. Some g-C 3 N 4 -based composites/nanocomposites used for the efficient PD of MO dye are consolidated in Table 1 .…”

(001)-TiO2 nanosheets loaded on BiOI improve carrier separation and enhance the photocatalytic activity

“…11(b), XRD analysis of the catalysts was also carried out, and the TB2 remained stable after the photocatalytic reaction, which met the requirements of the catalysts in practical applications. 46…”