In-Situ Fabrication of g-C3N4/ZnO Nanocomposites for Photocatalytic Degradation of Methylene Blue: Synthesis Procedure Does Matter

Abstract

The nanocomposite preparation procedure plays an important role in achieving a well-established heterostructured junction, and hence, an optimized photocatalytic activity. In this study, a series of g-C3N4/ZnO nanocomposites were prepared through two distinct procedures of a low-cost, environmentally-friendly, in-situ fabrication process, with urea and zinc acetate being the only precursor materials. The physicochemical properties of synthesized g-C3N4/ZnO composites were mainly characterized by XRD, UV–VIS diffuse reflectance spectroscopy (DRS), N2 adsorption-desorption, FTIR, TEM, and SEM. These nanocomposites’ photocatalytic properties were evaluated in methylene blue (MB) dye photodecomposition under UV and sunlight irradiation. Interestingly, compared with ZnO nanorods, g-C3N4/ZnO nanocomposites (x:1, obtained from urea and ZnO nanorods) exhibited weak photocatalytic activity likely due to a “shading effect”, while nanocomposites (x:1 CN, made from g-C3N4 and zinc acetate) showed enhanced photocatalytic activity that can be ascribed to the effective establishment of heterojunctions. A kinetics study showed that a maximum reaction rate constant of 0.1862 min-1 can be achieved under solar light illumination, which is three times higher than that of bare ZnO nanorods. The photocatalytic mechanism was revealed by determining reactive species through adding a series of scavengers. It suggested that reactive ∙O2− and h+ radicals played a major role in promoting dye photodegradation.

Synthesis of g‐C3N4, Zn3(PO4)2 and g‐C3N4/Zn3(PO4)2 Composites for Application in Photodegradation of Crystal Violet Dye under Solar Light

“…The C1s spectra (Figure 8b) of the samples shows three deconvoluted peaks at 285.8 eV, 284.6 eV, and 282.1 eV, which can be ascribed to sp 3 CÀ N bond, CÀ C bond and originated from pure graphitic carbon may be formed during slight decomposition of the carbon nitride and carbidic carbon in g-C 3 N 4 /Zn 3 (PO 4 ) 2 respectively. [64][65][66] The peak at 287.3 eV can be attributed to C=O, which can be agree with the previous reported literature. [67] The deconvolution of N 1s spectra showed four peaks (Figure 8c).…”

The controlled synthesis of g-C3N4/Cd-doped ZnO nanocomposites as potential photocatalysts for the disinfection and degradation of organic pollutants under visible light irradiation

“…Ammonium oxalate (AO), benzoquinone (BQ), and isopropanol (IPA) scavengers were used as capture agents to remove photogenerated h + , cO 2À , and cOH radicals, respectively. 41,42 When benzoquinone (BQ) was added to the dye solution, the Fig. 11 (a) Natural logarithm and (b) inverse of natural logarithm with the rate of the change in concentration with time for the 7% Cd-ZnO NPs, (25%, 50%, 55%, 60%, and 65)% g-C 3 N 4 /Cd-ZnO and 60% g-C 3 N 4 /ZnO NCs.…”

A Water-Dispersible Carboxylated Carbon Nitride Nanoparticles-Based Electrochemical Platform for Direct Reporting of Hydroxyl Radical in Meat

“…The absorption bands at 1480 and 1634 cm −1 were caused by the stretching vibration of C–N and C=N in heptazine. The peak at 1706 cm −1 corresponded to the bending mode of C=O, and the absorption peaks at about 1393 and 1580 cm −1 were the characteristic bands of -COO, demonstrating carbon nitride is functionalized with the carboxyl group successfully [ 31 ]. The band at around 2214 cm −1 arose from the stretching vibration of C≡N, and the appearance of cyano groups might be ascribed to the cleavage of bulk carbon nitride in the molten salt environment [ 32 ].…”