Photodegradation Of Methylene Blue Dye Research Articles

Polyaniline-supported g-C3N4/ZnO/Ag2CrO4 composite for photodegradation of methylene blue under visible light irradiation

Organic dyes are a major source of environmental pollution from different industries. To remove these recalcitrant, a novel ternary g-C3N4/ZnO/Ag2CrO4 and its polyaniline-supported (PANI) composites were synthesized using an “in situ” oxidative polymerization approach. XRD, SEM, UV–Vis DRS, and PL techniques were utilized to characterize the as-prepared composites. The photocatalytic efficiency was evaluated using a model organic pollutant, methylene blue (MB), and samples of the effluent of the textile industry. The as-synthesized ternary g-C3N4/ZnO/Ag2CrO4 (ZT3= 87.87 %) composite showed better photocatalytic performance than the single (5 %) and binaries (15–25 %) counterparts for MB degradation. The influence of various experimental settings on the photodegradation of MB dye was examined and these were an initial dye amount of 10 ppm, photocatalyst load of 0.15 g/L, and pH 10. Under optimized conditions, PANI-supported g-C3N4/ZnO/Ag2CrO4 composite (PAST) demonstrated substantial degradation efficiency (97.5 %). The reusability study of the spent catalyst revealed a reduced efficiency from 97.5 to 78.5 % photodegradation of MB after four successive cycles, demonstrating the photocatalyst's stability and efficiency. According to the study on the effect of scavengers, h+ plays a significant part in the discoloration of MB. The PAST photocatalyst outperformed the MB discoloration (97.5 %) and adequate degradation for real textile effluent samples (77.7 %) collected from Hawassa textile industries. The photodegradation efficiency result of this study demonstrated that PANI-supported g-C3N4/ZnO/Ag2CrO4 might serve as an advantageous photocatalyst for the efficient removal of MB and other dyes under visible light irradiation at the optimum conditions. The total estimated cost analysis of synthesis and photocatalytic degradation using Polyaniline-supported g-C3N4/ZnO/Ag2CrO4 composite found that it was quite affordable, costing around $5 per 1,000 L of wastewater treatment.

Synthesis of Reusable CNF/Ag2Se Films as Visible-Light-Driven Photocatalysts for Photocatalytic Degradation of MB

AbstractIn our study’s scenario, flexible films were fabricated from TEMPO-oxidized cellulose nanofibers and silver selenide (CNF/Ag2Se) as efficient membranes for the degradation of methylene blue (MB). Different concentrations of Ag2Se particles were in situ prepared in the presence of CNF. The in-situ synthesis of Ag2Se nanoparticles in the presence of CNF was reported as efficient technique for the formation of submicrosize Ag2Se particles with a narrow size distribution and homogeneous dispersion onto CNF. TEM analysis revealed that the nanofibers had uniform width and diameter, while XRD demonstrated single-phase orthorhombic β-Ag2Se formation. 3D-FESEM showed tiny root measurer values of 28, 30, and 32.56 nm in polymeric films with 2.5, 5, and 10% Ag2Se-filled CNF. Polymeric films had visible-driven-light photocatalytic activity because the band gap fell from 4.61 eV (UV area) to 2.71 eV (visible region). The composite’s photocatalytic performance was assessed by MB degradation. 10% of CNF/Ag2Se demonstrated maximal photocatalytic activity under simulated sunlight for 60 min, pH 9, and 3 g/L composite weight. The factorial design statistical analysis showed that MB dye photodegradation is mostly affected by irradiation time and dye concentration. Environmental, social, and economic factors are all considered, making this study suitable for implementing photocatalysis to large-scale water treatment systems, which is a key component of sustainability.

Sol-gel assisted β-cyclodextrin coated MoO3-Fe2O3 nanocomposite for photodegradation of methylene blue dye

Sol-gel assisted β-cyclodextrin coated MoO3-Fe2O3 nanocomposite for photodegradation of methylene blue dye

Synthesis, Crystal Structure and Spectral Characterization of a New Caesium–Sodium-Isopolyvanadate: Photodegradation of Methylene Blue Dye

Synthesis, Crystal Structure and Spectral Characterization of a New Caesium–Sodium-Isopolyvanadate: Photodegradation of Methylene Blue Dye

Characterization and photodegradation of methylene blue dye using bio-synthesized cerium oxide nanoparticles with Spirulinaplatensis extract

Increasing concern about environmental pollution attracts researchers to develop eco-friendly, low-cost, and sustainable approaches for green biosynthesis of nanoparticles to overcome pollutants. This study focuses on the green synthesis of ceria NPs using Spirulinaplatensis extract as a stabilizing and reducing agent. Characterization measurements, such as optical properties, X-ray diffraction, SEM, TEM, and FT-IR spectroscopy, confirmed the successful synthesis of crystalline and stable ceria NPs with well-defined morphological features. The calculated bandgaps energy of pure ceria, green CeO2@Sp 2:1, and CeO2@Sp 1:1 were 3.3, 3.15, and 2.94 eV, respectively. The as-synthesized and green ceria NPs showed an excellent degradation efficacy of MB dye under UV irradiation. Furthermore, the green ceria NPs showed high photodegradation efficiency of MB dye (R% = 86.2 and 88.8%) than pure ceria (R% = 76.4%) at certain specific conditions (pH = 11, contact time = 90 min, catalyst dose = 0.3 g/L and MB dye initial concentration = 100 mg/L). The isothermal constants confirmed that the degradation of MB dye is well-fitted with the Freundlich isotherm model (R2 > 0.99) better than the Langmuir model (R2 < 0.8). The kinetics models revealed a rapid degradation rate of MB dye, which follows pseudo-second-order models with Ce values ranging from 83.33 to 89.29 mg/g, with R2 > 0.99. These results indicated the potential applicability and promising avenue for developing advanced ceria NPs for wastewater treatment applications.

Photodegradation of methylene blue dye using graphene oxide incorporated, post-transition metal doped zinc oxide thin films by spray pyrolysis

Photocatalytic activity of graphene oxide incorporated pure and metal doped zinc oxide thin films were studied against methylene blue dye under simulated solar irradiation. Thin films were deposited on a glass substrate using an automated spray pyrolysis technique at a temperature of 425 °C. Aluminium, gallium, and indium were the post-transition metals used for doping. Graphene oxide content in the precursor solution was fixed at 0.00375 g/l. The formation of the wurtzite structure of zinc oxide has been confirmed using structural analysis. The average crystallite size of all the thin film samples was found to be in the range of 45–55 nm. The morphology and elemental composition of the films were studied using scanning electron microscopy and energy-dispersive x-ray spectroscopy. The energy band gap of the material was determined from UV–vis-NIR spectroscopic measurements using Tauc’s plot and it is in the range of 3.25–3.28 eV. Photoluminescence spectra of the as-deposited films were recorded. Intensity of the near band emission at 395 nm was found to decrease upon metal doping, indicating a better photocatalytic property. All the films were used for heterogeneous photocatalysis and the indium doped zinc oxide thin film incorporated with graphene oxide was found to be a better catalyst with an efficiency of 94.9% for degrading methylene blue dye in 180 min.

Retracted: Methylene Blue Dye Photodegradation during Synthesis and Characterization of WO3 Nanoparticles

Retracted: Methylene Blue Dye Photodegradation during Synthesis and Characterization of WO₃ Nanoparticles

Croton macrostachyus Leaf Extract-Mediated Green Synthesis of ZnO Nanoparticles and ZnO/CuO Nanocomposites for the Enhanced Photodegradation of Methylene Blue Dye with the COMSOL Simulation Model.

The photodegradation of organic pollutants using metal oxide-based catalysts has drawn great attention as an effective method for wastewater treatment. In this study, zinc oxide nanoparticles (ZnO NPs) and zinc oxide/copper oxide nanocomposites (ZnO/CuO NCs) were fabricated using the leaf extract of Croton macrostachyus as a nontoxic, natural reducing and stabilizing agent. The synthesized samples were characterized by employing X-ray diffraction, microscopic, spectroscopic, and electrochemical methods. The results confirmed the successful synthesis of ZnO NPs and ZnO/CuO NCs with well-defined crystalline structures and morphologies. The prepared samples were tested for the photodegradation of methylene blue (MB) dye under visible light irradiation. Compared to ZnO NPs, ZnO/CuO NCs showed greatly improved photocatalytic performances, particularly with the sample prepared with the 20 mol % Cu precursor (97.02%). The enhancement could be related to the formed p-n heterojunction, which can suppress the recombination of charge carriers and extend the photoresponsive range. A theoretical study of the photocatalytic activity of ZnO/CuO NCs against MB dye degradation was also conducted by using COMSOL Multiphysics software. The results of the simulation are in reasonable agreement with those of the experiment. This study contributes to the development of sustainable and effective photocatalytic materials that are suitable for application in environmental remediation, particularly in the treatment of wastewater.

EFFECT OF THE CONCENTRATION OF SILVER NANOPARTICLES ON THE PHOTOCATALYTIC ACTIVITY OF TITANIUM DIOXIDE NANORODS

In this paper the results of a study of the effect of the concentration of silver nanoparticles in films of titanium dioxide nanorods on their photocatalytic activity are presented.Titanium dioxide nanorods with a rutile structure was obtained usingthe method of hydrothermal synthesis. Due tochanging with the amount of substance of the transition metal silver salt (AgNO3) and chemical reduction on the surface of the titanium dioxide nanorods, Ag nanoparticles of different concentrations were obtained. The photocatalytic activity of the samples was assessed by the amount of photocurrent obtained from a unit of film surface and photodegradation of methylene blue dye when illuminating the surface with a light source of a Xenon lamp.Surface morphologies and energy dispersive X-ray studies showed that Ag nanoparticles were uniformly distributed and anchored on the titanium dioxide nanorods surface.

Enhanced photocatalytic degradation of methylene blue dye using eco-friendly synthesized rGO@ZnO nanocomposites

Industrial chemical pollutants such as methylene blue (MB) dye are released into the water body and potentially cause harm to the human and aquatic biosphere. Therefore, this study aims to synthesize eco-friendly nanocatalysts, i.e., reduced graphene oxide (rGO), zinc oxide (ZnO), and reduced graphene oxide-zinc oxide (rGO@ZnO) nanocomposites, for efficient photocatalytic degradation of MB dye. A graphite rod was obtained from waste dry cell batteries for the electrochemical exfoliation synthesis of graphene oxide (GO) and rGO. For the eco-friendly synthesis of ZnO and rGO@ZnO nanocatalysts, Croton macrostachyus leaf extract was used as a reducing and capping agent. The synthesized nanocatalysts were characterized using a UV–Vis spectrophotometer, Fourier transform infrared spectroscopy, X-ray diffraction, and scanning electron microscopy with energy-dispersive X-ray. The eco-friendly synthesized rGO, ZnO, and rGO@ZnO nanocatalysts were applied for the photocatalytic degradation of MB dye using direct sunlight irradiation. At optimum parameters, photocatalytic degradation of MB dye efficiency reached up to 66%, 96.5%, and 99.0%, respectively. Furthermore, kinetics of the photodegradation reaction based on rGO, ZnO, and rGO@ZnO nanocatalysts follow pseudo-first-order with a rate constant of 2.16 × 10–3 min−1, 4.97 × 10−3 min−1, and 5.03 × 10−3 min−1, respectively. Lastly, this study promotes a low catalyst load (20 mg) for the efficient photodegradation of MB dye.

G-C3N4/graphene oxide/SnFe2O4 ternary composite for the effective sunlight-driven photocatalytic degradation of methylene blue.

A broadly used dye, methylene blue (MB), adversely impacts human health and water resources, which triggers efficient methods for its elimination. Semiconductor-based heterogeneous photocatalysis is an environmentally friendly approach that effectively degrades organic pollutants. The purpose of the current work is to elucidate and validate the application of a promising g-C3N4/GO/SnFe2O4 (CGS) composite for the environmental remediation of methylene blue dye. The ternary CGS composite has been synthesized using a solvothermal approach. The fabricated composites were analyzed through FTIR, XRD, SEM/EDX, UV-VIS spectroscopy, TEM, and XPS. The photoactivity of composites and affecting parameters (pH, H2O2 dosage, composite amount, initial dye concentration, and irradiation time) were observed in sunlight illumination. The optimal conditions for photocatalytic degradation were pH = 5, photocatalyst dosage = 30 mg/100 mL, H2O2 dosage = 6 mM, and initial dye concentration (IDC) of 10 ppm employing ternary CGS composite, and MB dye was degraded effectively within 1 h. Ninety-eight percent degradation efficacy was attained by employing ternary CGS composite under the optimized conditions. Scavenging analysis suggested that •OH radicals were the key reactive oxygen species (ROS) responsible for the photodegradation of MB dye. Furthermore, the CGS nanocomposite exhibited outstanding recyclability of 84% after five consecutive runs, demonstrating its potential for use in practical applications, particularly pollutant removal.

Design and preparation of novel LaFeO3/NiFe2O4 nanohybrid for highly efficient photodegradation of methylene blue dye under visible light illumination

Most dyes are carcinogenic; thus, they must be removed from the water to save aquatic and human life. Among the various methods, the photocatalytic degradation of dyes is attracting much attention due to the easy strategy driven by the solar light. Herein, we report the fabrication of nickel ferrite (NiFO), lanthanum ferrite (LFO) and their composite are utilized as a light-driven catalyst for the deprivation of significant commercial dyes. The straightforward microemulsion method is used to produce both pure ferrite materials and their composite counterparts. The phases of the synthesized materials were verified through XRD analysis while scanning electron microscopy was employed to examine their morphology. The average crystallite size of the LFO, NiFO and their composite was 53, 62 and 42 nm, respectively. The elemental composition of the pristine and composite was confirmed by the energy dispersive spectroscopic analysis, indicating no other impurity in the materials. The optical properties are analyzed via UV visible and photoluminescence to measure the band gap value of 2.05, 1.73 and 1.9 eV for LFO, NiFO and their composite, respectively. It is observed that the LaFeO3/NiFe2O4 has the highest photodegradation efficiency (92 %) as compared to the LFO (LaFeO3) and NiFO (NiFe2O4). The composite material also showed excellent reusability as well as good stability. It was also confirmed that OH radicals are the major contributor toward the dye degradation, as confirmed by the scavenger tests. The higher mineralization of methylene blue in the occurrence of composite as a catalyst may cause rapid charge transfers, as confirmed by EIS, and it may stop the recombination of electrons/hole pairs due to suitable band alignments.

Biopolymer assisted synthesis of metal–silica hybrid nanoflowers as a medium for the photocatalytic degradation of dye pollutants

This report presents an ecofriendly synthesis and characterization of biopolymer (sodium alginate)-capped silver nanoparticle-silicon dioxide (Ag-SiO2) hybrid nanoflowers and their efficiency for the plasmon-mediated dye degradation of methylene blue. The reducing and capping agents for the initial silver nanoparticles (AgNPs) synthesis were glucose and sodium alginate, respectively. The mesoporous silica nanostructures were introduced using two-step hydrolysis followed by a polycondensation process. Detailed structural and morphological characterizations of the as-prepared hybrid nanostructures were done using various techniques. The results revealed the formation of nanoflower-like hybrid alginate-capped Ag-SiO2 nanostructures with a size range of approximately 523 ± 56 nm. The BET surface area analysis showed that the hybrid nanostructure has a surface area of 15.6 m2/g together with a pore diameter of 18.2 nm. The hybrid Ag-SiO2 nanoflowers showed excellent catalytic properties for the visible light photodegradation of methylene blue dye after 1 min exposure compared to silver nanoparticles at the same condition. The synergistic effect of SiO2 and Ag nanoparticles improved the catalytic property of the hybrid nanostructure. This study demonstrated a simple and effective model for the efficiency of designed hybrid nanostructures for degradation of industrial dyes.

Development and characterization of solar active Ag-ZnO/g-C3N4 as a highly efficient photocatalyst for the detoxification of organic pollutant

In today's biosphere, a major problem is water pollution caused by the discharge of effluents from dying industries, such as the printing and textile industries. In our current work, we have successfully fabricated photocatalytic bare and composite material 1%Ag-ZnO/6% g-C3N4 (Ag-ZnO/gCN), along with pristine ZnO and g-C3N4 (gCN), for the efficient degradation of dye wastewater. Structural investigations performed using FT–IR, XRD, FE–SEM/EDS, XPS, PL, EIS, and HR-TEM/EDS confirmed the structures of the pristine and composite photocatalysts. According to XPS studies, Ag exists in the metallic form. The photocatalytic performance of all the catalysts was evaluated by degrading methylene blue (MB) dye in an aqueous solution under direct sunlight illumination, and the most active composite catalyst was utilized for conducting dye degradation under visible light in the optimized experimental conditions. The effects of operating parameters, such as catalyst amount and initial pH, on MB degradation have been evaluated. Under solar irradiation, the photodegradation of MB dye over the Ag-ZnO/gCN composite catalyst was measured to be ≈ 100% in 50 min, and its degradation rate constant Kapp (0.1266 min–1) was higher than that of other pristine and composite catalysts. A Total Organic Carbon (TOC) study validated MB mineralization. Further experimental results corroborate the conclusion that superoxide radical anions (O2•–) play a pivotal role in this degradation process, with hydroxyl radicals (•OH) and photogenerated holes (h+) following suit insignificant. Moreover, after undergoing 5 consecutive cycles, the catalysts exhibited a remarkable photostability of 88%. A possible photocatalytic mechanism was proposed for the improved photocatalytic activity.

Photo(electro)catalytic Performance of ZnO‐Based Nanopowders Prepared through Pulse Alternating Current Electrosynthesis in Alkaline Earth Chloride Electrolytes

AbstractPhoto(electro)catalysis is a technology that allows abundant and clean solar energy to be harvested as an essential step to achieving sustainable development goals. However, controllable and economically viable synthesis of nanocatalysts is one of the key challenges that hinder the practical application of many important energy‐related photo(electro)catalytic reactions. In this study insights into the electrosynthesis of ZnO‐based materials using pulse alternating current as a green oxidant and the alkaline earth metal chloride aqueous solutions as electrolytes were provided. The effect of electrolyte on composition and structure of final products was demonstrated. ZnO photocatalyst prepared in BaCl2 exhibited different activity tendency in photoelectrocatalytic and photocatalytic systems showing the highest photocurrent (0.18 mA cm−2) for ZnO photoelectrode annealed at 300 °C and maximum rate constant for methylene blue dye photodegradation in the presence of ZnO particles annealed at 500 °C. Optimized ZnO nanopowder was further employed for the degradation of 2,4‐dinitrophenol pollutant in a custom‐designed flow photoreactor operating under low‐power UV. 2,4‐dinitrophenol was degraded to 90.1 % at ZnO dosage of 0.2 mg L−1 within 280 min of illumination. Overall, the optimization of pulse alternating current electrosynthesis and post‐annealing might be promising and sustainable approach to ZnO‐based nanopowders for environmental photo(electro)catalytic applications.

Ultrafast photodegradation of methylene blue dye and supercapacitor applications of flower like hydrothermal synthesized V2O5 nano -structures on rGO as nano - composite

In recent years, studies into the energy storage and water remediation are on the top priority of material scientists. Development of graphene-based materials for the purpose is a novel attempt in current research. Novel rGO - V2O5 nano composite having excellent photocatalytic and supercapacitor properties was designed and characterized in the present manuscript. V2O5, reduced graphene oxide (rGO) and rGO-V2O5 composite (with concentrations 1:0.5, 1:1, 1:2, and 1:3), were synthesized by hydrothermal method, standard modified Hummer's method followed by Hydrazine based reduction and sonochemical method, respectively. All the compounds were characterized by X-ray diffraction (XRD), Raman spectroscopy and Scanning Electron Microscopic techniques to study the structural and morphological aspects. Photocatalytic dye degradation experiments for Methylene Blue dye degradation and Electrochemical studies including cyclic voltammogram (CV), Galvanostatic Charging and Discharging (GCD), Electrochemical Impedance Analysis (EIS) experiments were performed on these compounds. XRD and Raman studies confirm the successful synthesis of these compounds and SEM images manifest excellent distribution of nano V2O5 on rGO sheets. At the concentration of 1:1, the rGO-V2O5 composite exhibits an ultrafast degradation of MB up to 94% under visible irradiations in just 8 min because of its narrow bandgap (2.4 eV) compared to the bare rGO (51%@135) and V2O5 (15%@22), respectively. Trapping-active-species experiment was performed to understand the MB degradation mechanism with rGO-V2O5, where the superoxide ion role has been found to be superior to other elements present in the degradation reaction. The optimized rGO-V2O5 (1:1) composite was further employed in the supercapacitors, showing a higher specific capacitance (Cs) of 818 F/g than that of the bare rGO (548 F/g) and V2O5 (246 F/g) at the 1 A/g of current density in 3 M KOH aqueous electrolytes. The results manifest ultrafast degradation and superior electrochemical performance for the designed composite of rGO and V2O5.

Black sand as a cost-effective catalyst for methylene blue photo-remediation under visible light

Methylene blue (MB) is commonly a persistent and perilous pollutant in industrial wastewater effluent. While MB has a massive negative effect on human and ecology safety. The neutralization of such harmful material would save a huge clean water amount. This work proposes the natural and abundant black sand as a catalyst for MB photodegradation. The sand sample was calcined at three temperatures of 300°, 400°, and 600 °C. The properties of samples were analyzed with different micro- as well as spectroscopic techniques. The experimental data revealed the sample's main composition of SiO2, Fe2O3, and Al2O3. XRD and XPS results proved the formation of mixed oxides composites due to calcination, especially at 400 °C. The UV–vis analysis conducted showed that samples can absorb light in the visible range. The photodegradation reached a maximum of 975.3%, 82.7%, and 75.7% for BS400, BS600, and BS300 respectively; by illumination for 2.5 h in the visible range. The observed distinguishable catalytic performance was discussed via the spectroscopic analysis and oxygen availability in the catalyst lattice. When AO, t-BuOH, and BQ are used as scavengers instead of just BQ during the photodegradation of MB dye over BS400 catalyst, the photodegradation rate drops significantly. The degradation % of MB dye diminished to 60%, and 70% by using AO, t-BuOH, and BQ scavengers; respectively. This proved that rather than hydroxyl radicals, superoxide radicals or positive hole production is the main determining step in MB photo-degradation over BS400 catalyst.

Imine-Decorated Copper-Based Metal-Organic Framework for the Photodegradation of Methylene Blue.

A low cost imine-decorated linker, 4,4'-(hydrazine-1,2-diylidenedimethylylidene)dibenzoic acid was utilized for the preparation of copper-based metal-organic framework (MOF) denoted as Cu-L via a solvothermal technique. The synthesized MOF material has been fully characterized by different analytical techniques such as Fourier-transform infrared (FT-IR) spectroscopy, powder X-Ray diffraction (PXRD), scanning electron microscopy (SEM), energy dispersive X-Ray spectroscopy (EDX), nitrogen adsorption-desorption isotherm analysis, and thermogravimetric analysis (TGA). It has been found that the coordination of Cu2+ with L considerably reduced the band gap of the L of nearly about 1eV, which is approximately 26% decline in total. Notably, a narrow band gap of the photocatalyst is an essential requirement for the proficient photodegradation of organic contaminants. An excellent optical properties and narrow band gap of (2.8eV) of Cu-L ensure their suitability as a photocatalyst for the degradation of methylene blue (MB) dye. In the presence of Cu-L photocatalyst, 84.22% degradation of MB dye was observed after 150min under sunlight exposure. It is the first time that imine-functionalized MOF was utilized for the degradation of MB dye under sunlight irradiation. For understanding the photodegradation of MB dye by the Cu-L photocatalyst, all the plausible mechanistic studies have been carried out in detail. Both theoretical (with the help of density functional theory (DFT) calculations) as well as experimental studies have been conducted to justify the possible mechanisms for the photodegradation of MB dye by Cu-L. The current work may open a new opportunity to construct a cheap MOF-based photocatalysts for fast degradation of dye contaminants.

Surface embellishment accelerates the oxygen evolution reaction and removal of organic pollutant using solvothermally designed Co2O3/CuO nanocomposite

This study generates a heterostructure composed of Co2O3/CuO via a simple hydrothermal procedure as an effective OER electrocatalyst and photocatalyst. The fabricated electrode material was then analyzed to confirm the structural, morphological, and textural analysis using various methods. The nanoparticles decorated on rods nanocomposite are helpful for the electrochemical and photochemical reactions with a higher BET surface area of 112 m2 g−1. For the electrochemical investigation, CV (cyclic voltammetry), LSV (liner sweep voltammetry), EIS (electrochemical impedance), chronoamperometry, and ECSA (electrochemical active surface area) tests are performed. The fabricated electrode material showed an outstanding overpotential of 272 mV to attain 10 mA cm−2 current density, with a low Tafel value of 40 mV dec−1. The designed material is also utilized for the photodegradation of methylene blue dye with 98 % degradation under solar light and retains its stability for up to 5 cycles. The increased various active sites, more surface area, and superior charge transport properties of Co2O3/CuO explain its greater OER and degradation efficiency than its pristine oxides. The resultant material will be useful for many industrial applications in future.

Titanium Dioxide (TiO2) Modified Bentonite for Photodegradation in Methylene Blue Dye

Dye is one of the waste waters, which will be a problem if the content is excessive in the water. Modifying bentonite with titanium dioxide (TiO2) as a photocatalyst for removal of dye waste. In this study, composite synthesis was carried out by mixing bentonite and TiO2 suspensions. The mass of bentonite is 20 g, and the mass variations of TiO2 are 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, and 100%. The resulting composite was heated using a furnace at 550°C for 5 hours. Bentonite-TiO2 composites were characterized using Fourier Transform Infrared, X-Ray Diffraction, and Scanning Electron Microscope-Energy Dispersive X-Ray (SEM-EDX). Photodegradation of methylene blue dye with bentonite-TiO2 was carried out by varying the mass of bentonite-TiO2 photocatalysts (0.02, 0.04, 0.06, 0.08 g); variations in pH (1, 3, 5, 7, and 9), and variations in UV irradiation time (30, 60, 90, and 120 minutes). The results of characterization with FTIR showed the presence of Ti-O-Ti vibrations at wavenumber 1419 cm-1 and Si-O-Ti at wave numbers 780 cm-1 and 799 cm-1. Characterization of 20% bentonite-TiO2 by XRD showed rutile, anatase, and montmorillonite phases. The SEM-EDX bentonite-TiO2 characterization results produced some small particles with a layered structure with TiO2 particles clumping and still in the form of agglomerates, and the EDX results showed the chemical composition of Si and Ti. The results of photodegradation showed that the best activity for the bentonite-TiO2 composite occurred in photocatalyst BT-20% with a mass of 0.08 g, pH 1, and UV irradiation time of 120 minutes with methylene blue 99.942% degraded.