Preparation of PANI Modified ZnO Composites via Different Methods: Structural, Morphological and Photocatalytic Properties

Abstract

Polyaniline modified zinc oxide (PANI-ZnO) photocatalyst composites were synthesized by focusing on dissolution disadvantage of ZnO. In-situ chemical oxidation polymerization method was performed under neutral conditions (PANI-ES) whereas in hybridization method physical blending was applied using emeraldine base of polyaniline (PANI-EB). PANI-ZnO composites were prepared in various ratios of aniline (ANI) to ZnO as 1%, 3%, 6% and 9%. The alterations on the structural and morphological properties of PANI-ZnO composites were compared by Fourier Transform Infrared (FT-IR), Raman Spectroscopy, X-Ray Diffraction (XRD) and Scanning Electron Microscopy-Energy Dispersive X-ray Analysis Unit (SEM-EDAX) techniques. FT-IR and Raman spectroscopy confirmed the presence of PANI in all composites. SEM images revealed the morphological differences of PANI-ZnO composites based on PANI presence and preparation methods. Photocatalytic performances of PANI-ZnO specimens were investigated by following the degradation of methylene blue (MB) in aqueous medium under UVA irradiation. The effects of catalyst dose and initial dye concentration were also studied. MB degradation was followed by both decolorization extents and removal of aromatic fractions. PANI-ZnO composites expressed enhanced photocatalytic performance (~95% for both methods) as compared to sole ZnO (~87%). The hybridization method was found to be more efficient than the in-situ chemical oxidation polymerization method emphasizing the significance of the neutral medium.

Recent Advances in the Removal of Organic Dyes from Aqueous Media with Conducting Polymers, Polyaniline and Polypyrrole, and Their Composites

“…This is based on the observation that any material in contact with the reaction mixture becomes coated with a thin submicrometre film [ 44 ], which is well suited for adsorption purposes. The coating of inorganic substrates is represented by the following: barium titanate [ 45 ]; cobalt ferrite [ 28 ]; cobalt sulfide [ 46 ]; copper(II) oxide [ 47 ]; fly ash [ 48 ]; iron oxyhydroxide [ 49 ]; iron sulfide [ 21 ]; magnetite [ 50 ]; manganese(IV) dioxide [ 34 , 40 ]; manganese ferrite [ 51 ]; magnesium ferrite [ 52 ]; molybdenum trioxide [ 53 ]; montmorillonite [ 54 ]; nickel oxide [ 40 ]; silica gel [ 55 ]; tin dioxide [ 56 ]; titanium dioxide [ 22 , 33 , 57 , 58 ]; zeolite [ 59 ]; zinc oxide [ 60 , 61 , 62 ]; zirconium(IV) dioxide [ 63 ].…”

“…The organic substrates coated with conducting polymers include synthetic polymers, such as carboxymethylcellulose gel [ 78 ], Kevlar fibers [ 73 ], macroporous melamine sponges [ 16 ], poly(ethylene oxide) [ 76 ], polyimide membrane [ 74 ], polystyrene [ 64 ], poly(vinyl alcohol) aerogel [ 42 ], polyurethane foam [ 77 ], and various natural materials, such as [ 24 , 75 ], chitosan [ 82 ], opuntia ficus [ 80 ], almond and wall nut shells [ 81 ] or tea saponin [ 41 ]. Only exceptionally, both components were simply mixed, e.g., polyaniline and nitrogen-containing carbon nanodots [ 87 ] or zinc oxide [ 61 ]. In this case, the fact that the organic component may also be an efficient adsorbent in addition to conducting polymer also has to be kept in mind [ 16 ].…”

“…The list of simple polyaniline composites includes the following moieties: bismuth oxychloride [ 95 ]; cadmium sulfide [ 96 , 97 ]; carbon nitride [ 98 ]; magnetite [ 89 ]; multiwall carbon nanotubes [ 99 ]; nickel [ 100 ]; reduced graphene oxide [ 101 ]; silver molybdate [ 29 ]; silver oxide [ 102 ]; tin dioxide [ 103 ]; titanium dioxide [ 104 , 105 , 106 ]; tungsten trioxide [ 107 ]; zinc oxide [ 61 , 104 , 108 , 109 , 110 ]; zirconium dioxide [ 9 ].…”

Comparative Kinetic and Isotherm Studies of Methyl Orange Dye adsorption using ZnO/PANi composite materials

“…The positive strain value indicates a tensile strain, whereas the negative value indicates a compressive strain. All the characteristics peaks of ZnO are slightly shifted to higher 2θ values in 70PANI/30ZnO nanocomposite than shifted towards lower 2θ values with increasing of PANI content, which may be due to the strong interaction between PANI and ZnO nanoparticles [30][31][32]. This indicated that in-suit formed zinc oxide nanoparticles well incorporated into polyaniline matrix.…”

New Perspectives in Photocatalytic Water Treatment

“…has been investigated for the last two decades. PANI-modified ZnO was used for the degradation of methylene blue dye that was selected as a model compound [4]. The major dissolution disadvantage of ZnO was eliminated by employing an in situ chemical oxidation polymerization method under neutral conditions (PANI-ES), whereas in the hybridization method, physical blending was applied using an emeraldine base of polyaniline (PANI-EB).…”