A visible light driven nanocomposite containing AgBr and sheet-like g-C3N4 was prepared by precipitation of AgBr nanoparticles (NPs) onto the surface of g-C3N4 nano-sheets. The composite system showed a significant enhancement in photocatalytic activity with respect to the mono-component systems in the degradation of methyl orange (MO) under visible light irradiation. Different methods including, bulky, thermal oxidation, protonation, and ultra-sonication were used for synthesis of g-C3N4 nanosheets. The resulted g-C3N4 samples were then modified by AgBr NPs via deposition-precipitation (DP) method. Among them, the catalyst containing the ‘protonated g-C3N4’ showed the best photocatalytic activity. The composite with AgBr:g-C3N4 mole ratio of 2:1 containing the ‘protonated g-C3N4’ showed the best activity. Different coupling techniques including: ‘grinding’, ‘grinding-ultra-sonication’, ‘ultra-sonication/deposition-precipitation’ and ‘ultra-sonication/deposition-precipitation/ultra-sonication’ were used for coupling of the protonated g-C3N4 with AgBr NPs. Among these catalysts, two later cases showed the best photocatalytic activities. Among the type II- heterojunction and the direct Z-scheme mechanisms, later case well described the boosted photocatalytic activity of the composite with respect to the mono-component systems.

A visible light driven AgBr/g-C3N4 photocatalyst composite in methyl orange photodegradation: Focus on photoluminescence, mole ratio, synthesis method of g-C3N4 and scavengers

The cost-effective, robust, and efficient electrocatalysts for photoelectrochemical (PEC) water-splitting has been extensively studied over the past decade to address a solution for the energy crisis. The interesting physicochemical properties of CuO have introduced this promising photocathodic material among the few photocatalysts with a narrow bandgap. This photocatalyst has a high activity for the PEC hydrogen evolution reaction (HER) under simulated sunlight irradiation. Here, the recent advancements of CuO-based photoelectrodes, including undoped CuO, doped CuO, and CuO composites, in the PEC water-splitting field, are comprehensively studied. Moreover, the synthesis methods, characterization, and fundamental factors of each classification are discussed in detail. Apart from the exclusive characteristics of CuO-based photoelectrodes, the PEC properties of CuO/2D materials, as groups of the growing nanocomposites in photocurrent-generating devices, are discussed in separate sections. Regarding the particular attention paid to the CuO heterostructure photocathodes, the PEC water splitting application is reviewed and the properties of each group such as electronic structures, defects, bandgap, and hierarchical structures are critically assessed.

https://onlinelibrary.wiley.com/doi/pdf/10.1002/adma.202007285

Photoelectrochemical Water-Splitting Using CuO-Based Electrodes for Hydrogen Production: A Review

We unprecedentedly report that layered MnO₂ nanosheets were in situ formed onto the surface of covalently bonded graphitic carbon nitride/reduced graphene oxide nanocomposite (g-C₃N₄/rGO), forming sheet-on-sheet structured two dimension (2D) graphitic carbon nitride/reduced graphene oxide/layered MnO₂ ternary nanocomposite (g-C₃N₄/rGO/MnO₂) with outstanding catalytic properties on thermal decomposition of ammonium perchlorate (AP). The covalently bonded g-C₃N₄/rGO was firstly prepared by the calcination of graphene oxide-guanidine hydrochloride precursor (GO-GndCl), following by its dispersion into the KMnO₄ aqueous solution to construct the g-C₃N₄/rGO/MnO₂ ternary nanocomposite. FT-IR, XRD, Raman as well as the XPS results clearly demonstrated the chemical interaction between g-C₃N₄, rGO and MnO₂. TEM and element mapping indicated that layered g-C₃N₄/rGO was covered with thin MnO₂ nanosheets. Furthermore, the obtained g-C₃N₄/rGO/MnO₂ nanocomposite exhibited promising catalytic capacity on thermal decomposition of AP. Upon addition of 2 wt % g-C₃N₄/rGO/MnO₂ ternary nanocomposite as catalyst, the thermal decomposition temperature of AP was largely decreased up by 142.5 °C, which was higher than that of pure g-C₃N₄, g-C₃N₄/rGO and MnO₂, respectively, demonstrating the synergistic catalysis of the as-prepared nanocomposite.

https://www.mdpi.com/2079-4991/7/12/450/pdf

Constructing Sheet-On-Sheet Structured Graphitic Carbon Nitride/Reduced Graphene Oxide/Layered MnO₂ Ternary Nanocomposite with Outstanding Catalytic Properties on Thermal Decomposition of Ammonium Perchlorate.

Microwave-assisted synthesis of graphitic carbon nitride/CuO nanocomposites and the enhancement of catalytic activities in the thermal decomposition of ammonium perchlorate

Catalytic activities of two different morphological nano-MnO2 on the thermal decomposition of ammonium perchlorate

Enhanced catalytic activity of mesoporous graphitic carbon nitride on thermal decomposition of ammonium perchlorate via copper oxide modification

Novel graphitic carbon nitride/CuO (g-C₃N₄/CuO) nanocomposite was synthesized through a facile precipitation method. Due to the strong ion-dipole interaction between copper ions and nitrogen atoms of g-C₃N₄, CuO nanorods (length 200-300 nm, diameter 5-10 nm) were directly grown on g-C₃N₄, forming a g-C₃N₄/CuO nanocomposite, which was confirmed via X-ray diffraction (XRD), transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM), and X-ray photoelectron spectroscopy (XPS). Finally, thermal decomposition of ammonium perchlorate (AP) in the absence and presence of the prepared g-C₃N₄/CuO nanocomposite was examined by differential thermal analysis (DTA), and thermal gravimetric analysis (TGA). The g-C₃N₄/CuO nanocomposite showed promising catalytic effects for the thermal decomposition of AP. Upon addition of 2 wt % nanocomposite with the best catalytic performance (g-C₃N₄/20 wt % CuO), the decomposition temperature of AP was decreased by up to 105.5 °C and only one decomposition step was found instead of the two steps commonly reported in other examples, demonstrating the synergistic catalytic activity of the as-synthesized nanocomposite. This study demonstrated a successful example regarding the direct growth of metal oxide on g-C₃N₄ by ion-dipole interaction between metallic ions, and the lone pair electrons on nitrogen atoms, which could provide a novel strategy for the preparation of g-C₃N₄-based nanocomposite.

Direct Growth of CuO Nanorods on Graphitic Carbon Nitride with Synergistic Effect on Thermal Decomposition of Ammonium Perchlorate

The invention discloses a g-C3N4/CuO composite material as well as a preparation method and application thereof and belongs to the field of material preparation and energetic materials. The composite material is formed by compounding g-C3N4 and CuO according the mass ratio of (99:5)-(80:20). The preparation method comprises the following steps: placing g-C3N4 and Cu(NO3)2.3H2O in an ethanol solution to be subjected to ultrasonic dispersion and stirring, after completion, grinding in an agate mortar until the mixture is pasty, placing the mixture in a drying oven to be dried, and roasting in a tube furnace, so as to obtain the g-C3N4/CuO composite material. The prepared g-C3N4/CuO composite material is applied to catalytic decomposition of ammonium perchlorate, and shows a good catalytic effect. The decomposition temperature of ammonium perchlorate is reduced to 318.3 DEG C. Compared with the prior art, the g-C3N4/CuO composite material and the preparation method have the advantages as follows: the preparation process is simple, and good repeatability, a high preparation speed and high preparation efficiency are achieved.

Shiying Li

Papers

Enhanced catalytic activity of mesoporous graphitic carbon nitride on thermal decomposition of ammonium perchlorate via copper oxide modification

Direct Growth of CuO Nanorods on Graphitic Carbon Nitride with Synergistic Effect on Thermal Decomposition of Ammonium Perchlorate

G-C3N4/CuO composite material as well as preparation method and application thereof