Co₂O₃‐NH₂‐MCM‐41 Decorated Graphite as an Effective Electrode: Synthesis, Characterization and its Application for Electro‐catalytic Oxidation of Acid Red 1

Abstract

1IntroductionDyes have been extensively used for thousands of years in textile [1],p rinting [2],p igments [3] and other applications.N owadays,w ith the rapid development of industries,d yes play ac ritical role in many fields. These are however plentifully discharged, leadingt oe ffluents having strong acidity or alkalinity,l arge amounts of colored species, huge amount of surfactant and even various harmful heavy metals like Cu, Cr and Ni [4].T heir intense color could reduce the transmission of sunlight throughw ater and thust he aquatic plants would be impacted;t hey are also hazardoust oa quatic organisms due to their cancerigenic property [5].H ence,r emoval of dyes from effluents is one of the most important environmentali ssues and admits of no delay.Mostly used conventionalm ethods for removing dyecontained waste water are chemical precipitation, membrane separation, catalytic oxidation, adsorption, electrochemical method and ozonation [ 6].A mong these treatments,c atalytic oxidation processes are considered as promising methods due to the in situ production of strong oxidants,m ainly hydroxyl radical( COH), and electro-catalytic oxidation has receivedg reat attention recently for the removal of organic pollutants,i ncludingd yes [7]. Moreover, the adsorption process is easy to manipulate, effective and cheap,w hich makes the combination of adsorptiona nd electro-catalytic oxidation to be both economical and efficient for removal of dyes.Thee lectrode materials play av ery important role in electro-catalytic oxidation. Many researchers have investigated lots of electrode materials,s uch as Au [8],I rO 2 [9],P d[ 10] and Pt-Ru alloys [11].A lthough electro-catalytic oxidation basedo nt hese materials exhibit good activities,high costs of these materials lead to the utilization of some less expensivem aterials,s uch as carbon, iron etc.[12].C orrosion of metallic materials during catalyst process limits the application of metals,w hich calls for utilization of carbon materials as efficient substitutes for solving these problems.A mongn umerousc arbonm aterials,g raphite has properties like high temperature resistance,c orrosionr esistance, porosity, large surface area and good conductivity [13].W hatsm ore,g raphite is perfectly suitable for acting as catalyst support due to its unique mechanical and electronic properties [14].M any previous literatures supported Co 2 O 3 as catalyst on electrode to acquire better catalytic efficiency [15].H ence,a pplying ac oating of Co on electrode could raise the activity of the electrode and the efficiencyo fe lectro-catalytic oxida-Abstract:T he graphite electrode decoratedw ith Co 2 O 3 -NH 2 -MCM-41w as successfully fabricated and the potential for applyingt his electrode for electro-catalytic oxidation of Acid Red 1( AR1)w as investigated.T he Co 2 O 3 -NH 2 -MCM-41w as characterized by Scanning Electron Microscope (SEM), Brunauer-Emmett-Teller (BET), Xray diffraction (XRD) and Fourier transform infrared spectra (FTIR). Electrochemicalm easurementsi ncluding cyc...

Formation of Nanocrystalline Cobalt Oxide-Decorated Graphene for Secondary Lithium-Air Battery and Its Catalytic Performance in Concentrated Alkaline Solutions

“…Ehrhardt et al indicated that Co 2 O 3 and Co 3 O 4 were likely to form simultaneously [ 43 ]. However, our sample was indexed to be mainly Co 3 O 4 (with 2θ = 19.0°, 36.9°, and 44.8° as described in PDF #42-1467) without the formation of Co 2 O 3 (whose XRD patterns are shown at 2θ = 51.2°, 56.3°, and 67.3° as described in PDF #02-0770 [ 44 ]). These results indicated that the hydrolysis reaction enabled the cobalt compound’s nucleation onto the GR sheets.…”