Novel g‐C₃N₄ nanosheets/CDs/BiOCl photocatalysts with exceptional activity under visible light

Abstract

We fabricated novel ternary nanocomposites through integration of C‐dots (carbon dots), BiOCl, and nanosheets of graphitic carbon nitride (g‐C3N4 nanosheets) by a cost‐effective route. The fabricated photocatalysts were subsequently characterized by XRD, EDX, TEM, HRTEM, XPS, FT‐IR, UV‐vis DRS, TGA, BET, and PL methods to gain their structure, purity, morphology, optical, textural, and thermal properties. In addition, the degradation intermediates were identified by gas chromatography‐mass spectroscopy (GC‐MS). Photocatalytic performance of the synthesized samples was studied by photodegradations of three cationic (RhB, MB, and fuchsine), one anionic (MO) dyes, one colorless (phenol) pollutant and removal of an inorganic pollutant (Cr(VI)) under visible light. It was revealed that the ternary nanocomposite with loading 20% of BiOCl illustrated superlative performances in the selected photocatalytic reactions compared with the corresponding bare and binary photocatalysts. Visible‐light photocatalytic activity of the g‐C3N4 nanosheets/CDs/BiOCl (20%) nanocomposite was 42.6, 27.8, 24.8, 20.2, and 15.9 times higher than the pure g‐C3N4 for removal of RhB, MB, MO, fuchsine, and phenol, respectively. Likewise, the ternary photocatalyst showed enhanced activity of 15.3 times relative to the g‐C3N4 in photoreduction of Cr(VI). Moreover, the ternary nanocomposite exhibited excellent chemical stability and recyclability after five cycles. Finally, the mechanism for improved photocatalytic performance was discussed based on the band potential positions.

Pharmaceuticals and personal care products in water and wastewater: a review of treatment processes and use of photocatalyst immobilized on functionalized carbon in AOP degradation

“…However, some of the challenges encountered with the use of photosensitive semiconductors as catalysts are low quantum efficiency, rapid recombination of photogenerated carriers, narrow optical response, and a slow transfer rate of electrons to oxygen which hinder their applications in the treatment of organic pollutants [143]. These limitations could be eliminated by employing strategies such as the modification of the textural properties, heterojunction construction, elemental doping, and morphology control to improve their photocatalytic performance [141].…”

“…Nano-photocatalysts consist of nano-size order metal oxides, with semiconducting properties and strong ability to degrade large varieties of persistent organic pollutants such as dyes, detergents, pesticides, and volatile organic compound that WWTPs cannot remove [138,139]. Quite several semiconductors such as ZnO, SrTiO 3 , Fe 2 O 3, SnO 2 , CuO 2 , WO 3, and Fe 3 O 4 have been used for the decomposition of organic pollutants from different environmental matrices [139][140][141]. They can also be used for degrading halogenated and non-halogenated organic compounds, PPCPs, and heavy metals in some specific situations [7].…”

Synthesis and photocatalytic H2‐production activity of plasma‐treated Ti3C2Tx MXene modified graphitic carbon nitride

“…To date, various photocatalysts have been studied, such as sulfides, oxides, graphitic carbon nitride . As a metal‐free polymer semiconductor, the graphitic carbon nitride (g‐C 3 N 4 ) has been developed as a photocatalytic material because of suitable band gap, good stability, high specific surface area and simple preparation methods . Due to a band gap of 2.7 eV, g‐C 3 N 4 is an optional photocatalyst for H 2 production in visible light range .…”

“…[10][11][12][13] As a metal-free polymer semiconductor, the graphitic carbon nitride (g-C 3 N 4 ) has been developed as a photocatalytic material because of suitable band gap, good stability, high specific surface area and simple preparation methods. [14][15][16] Due to a band gap of 2.7 eV, g-C 3 N 4 is an optional photocatalyst for H 2 production in visible light range. [17][18][19][20] However, bulk g-C 3 N 4 without any co-catalyst possesses a very low rate of hydrogen generation due to the high recombination rate of electron-hole pairs.…”

LaCoO3 acts as a high‐efficiency co‐catalyst for enhancing visible‐light‐driven tetracycline degradation of BiOI

“…Finally, in order to definitely elucidate the promotion mechanism, reactive species trapping experiments were employed to determine the predominant active species in the TC degradation processes over the LaCoO 3 /BiOI hybrid. In this investigation, triethanolamine (TEOA), 1, 4‐benzoquinone (BQ), and tert‐butyl alcohol ( t ‐BuOH) were chosen as the quenchers of photogenerated holes, superoxide radicals and hydroxyl radicals, respectively. As presented in Figure D, it could be clearly seen that the TC removal efficiency was severely inhibited after adding BQ or bubbling N 2 (to remove oxygen that was dissolved in the solution), and the same phenomenon could be observed when the TEOA was added, demonstrating that superoxide radicals and photo‐induced holes were the main reactive species of LaCoO 3 /BiOI in the photocatalytic degradation process of TC.…”