Hierarchically Grown NiO-Decorated Polyaniline-Reduced Graphene Oxide Composite for Ultrafast Sunlight-Driven Photocatalysis

Abstract

Polymers and transition-metal oxides have gained great interest as a photocatalyst in environmental remediation. They could be modified with each other in order to improve their activity. Here, a sunlight-responsive hierarchically structured ternary composite of nickel oxide, polyaniline, and reduced graphene oxide (NiO@PANI/RGO) has been synthesized and employed as a catalyst for dye [methylene blue (MB)] degradation. PANI/GO synthesized by interfacial polymerization acts as a matrix for the growth of NiO using a microemulsion solvothermal method, ensuing an in situ reduction of graphene oxide during the formation of a hierarchical NiO@PANI/RGO composite. Morphological studies of the as-synthesized NiO@PANI/RGO composite reveal fine NiO (10 nm) nanoparticles intercalated between the uniformly grown PANI spines (50–60 nm) over the RGO surface. The optical band gap of ∼1.9 eV calculated from the UV–vis spectrum illustrates the extended light absorption range for the NiO@PANI/RGO photocatalyst. The efficiency of 98% MB degradation within 11 min with the degradation rate constant 0.086 min –1 for NiO@PANI/RGO has surpassed any other report on metal oxide/graphene-based ternary composites. Overall, this work could pave the way for the fabrication of futuristic hierarchical structured ternary nanocomposites as an efficient photocatalyst and facilitate their application in the environmental protection issues.

Photocatalytic Degradation of Organic Dyes with Magnetically Separable PANI/Fe3O4 Composite under Both UV and Visible‐light Irradiation

“…Where C 0 , C t , k and t are the initial concentration, the final concentration, first-order rate constant and irradiation time. [50] The degradation of all dyes obeys a pseudo-first-order kinetic model (R 2 < 1) which was in worthy agreement with previous similar materials. [51,52,21] The k values were found to be 0.1997, 0.0521, and 0.1993 min À 1 , for MG, JK and LR, respectively under UV light illumination.…”

Fur-Imine-Functionalized Graphene Oxide-Immobilized Copper Oxide Nanoparticle Catalyst for the Synthesis of Xanthene Derivatives

“…20,22 Graphene and graphene oxide (GO) have excellent mechanical strength, electron transport properties, large specific surface area, good adsorption capacity, high chemical, and thermal stability. 21−23 GO and its nanocomposites have a wide range of applications as catalysts, 24−29 photocatalysts, 30−32 energy storage, 33 sensors, 34−36 hydrogen storage, 37 drug delivery, 38 biomedical devices, 39 super-capacitors, 40,41 and waste water treatment. 42,43 In the backdrop of their excellent synergistic action, GO-based nanocatalysts are rationalized using nanoparticles (NPs) adorning its surface for them to be used as heterogeneous catalysts to overcome different economic and environmental problems.…”

Recent progresses in photocatalytic hydrogen production: design and construction of Ni‐based cocatalysts

“…Among them, NiO nanoparticles own high hole mobility, low-cost, unique electric, and catalytic properties. 76 Yin et al 77 designed and prepared the p-n heterojunction of TiO 2 /NiO hybrid shells by a combined sol-gel and hydrothermal strategy, as shown in Figures 3A-D. The NiO nanoparticles coated on the surface of TiO 2 could significantly enhance photocatalytic performance for H 2 production and dye degradation under visible light irradiation.…”

“…Nickel oxides and hydroxides are more convenience to be prepared via some facile methods, or controlled their formation, structure, size, and morphology in comparison to other Ni‐based compounds. Among them, NiO nanoparticles own high hole mobility, low‐cost, unique electric, and catalytic properties 76 . Yin et al 77 designed and prepared the p‐n heterojunction of TiO 2 /NiO hybrid shells by a combined sol‐gel and hydrothermal strategy, as shown in Figures 3A‐D.…”