Wet Chemical Route Research Articles

Photothermal Conversion Boosted Photocatalytic CO2 Reduction over S-Scheme CeO2@Cu-TCPP: In Situ Experiments and DFT Calculations

Herein, interfacial and defect-engineering strategies synergistically promote photocatalytic properties. Because of the matching energy levels and the close interfacial contact, the CeO2@Cu-TCPP S-scheme architecture is successfully constructed via the in situ wet chemistry route. Photothermal conversion assists abundant OVs on the CeO2 compartment. Strong evidence of an S-scheme charge transfer path is verified by density functional theory (DFT) calculations and in situ irradiated X-ray photoelectron spectroscopy (XPS). This S-scheme heterojunction system is more deep-seated in facilitating the separation and transfer of photogenerated carriers as well as acquiring strong photoredox ability. Meanwhile, the abundant OVs proved by XPS and electron paramagnetic resonance spectra (ESR) enhanced the light-harvesting capacity and conductivity and shortened the transfer route. As a result, this synergistic heterojunction could mostly promote photocatalytic CO2 activation. The typical 0.25CeO2@ Cu-NS exhibited the best photocatalytic CO2RR to form CO and CH4 (rate: 229.6 μmol·g–1), which is even 45.8- and 1.5-folds higher than those of pristine LA-CeO2 (5.0 μmol·g–1) and Cu-TCPP (152.2 μmol·g–1), respectively, higher than those of other reported CeO2-based photocatalysts. This study presents a reinforcement and matrix prospect for domain charge behaviors to accelerate CO2 activation.

Rational design of a novel MnO2-FeSe2 nanohybrid with nanowires/cubic architecture as promising supercapattery electrode materials

A promising MnO2-FeSe2 nanohybrid is reported for the first time by the wet-chemical assisted route and directly utilized as a synergistic electrode for supercapattery applications. The optimized electrochemical performance of the MnO2-FeSe2 nanohybrid is realized when tested for capacitive signature and active redox reactions. Testing for capacitive signature and active redox reactions reveals the MnO2-FeSe2 nanohybrid's enhanced electrochemical performance. The MnO2-FeSe2 nanohybrid has a greater capacitance due to the cyclic voltammetry's bigger enclosed loop area, higher current response, and longer discharge time frame. Also, due to the synergistic impact between the two pseudocapacitive materials in the three-mode assembly, the least resistance in the impedance plot was attained when compared with MnO2 and FeSe2 electrodes. Based on these striking results, MnO2-FeSe2||AC||KOH supercapattery displayed a highly stable performance (95.3% retention) at the highest current response when run for 10,000 repeated discharge-charge cycles. It achieved a high energy of 55.39 Wh/kg at the power delivery of 4320 W/kg by expanding the upper voltage cutoff to 1.7 V in an aqueous medium. Our research paves a new way to develop metal selenide nanohybrid electrodes with conventional pseudocapacitive materials that could efficiently boost the electrochemical properties of the parent materials owing to the synergistic effect. The acquired results displayed the potential growth of MnO2 and FeSe2 nanohybrid as the future active materials for sustainable and clean energy storage devices.

SYNTHESIS OF COBALT FERRITE NANOPARTICLES AND THEIR APPLICATIONS IN HYPERTHERMIA THERAPY

Co-ferrite nanoparticles have been prepared by wet chemical route using micelles. Two sets of particles with sizes of⁓100 nm and ⁓200 nm were obtained by varying the concentration of micelles. The morphological and crystallographicstudy of the particles was performed by scanning electron microscope (SEM) and x-ray diffractometer respectively. Tocheck the suitability of the co-ferrite nanoparticles in magnetic hyperthermia therapy, various magnetic measurementswere carried out in presence of AC and DC magnetic fields. To investigate the suitability of the particles in hyperthermiatherapy hysteresis loss of the particles under the application of AC magnetic field with various frequencies has beencarried out. The parabolic nature of power loss with the frequency of the applied AC field has been verified fromexperimental data. From various measurements, it appeared that the particles with an average size ~100 nm have betterefficiency in view of hyperthermia therapy. A large value of the specific absorption rate (SAR) was found from the achysteresis of the particles.

Adsorption of hexavalent chromium from water using graphene oxide/zinc molybdate nanocomposite: Study of kinetics and adsorption isotherms

Hexavalent chromium is one of the most hazardous contaminants that threaten the environment. The present research work involves the synthesis of Graphene Oxide/Zinc molybdate (GO/ZM) nanocomposite by wet chemical route. The structure and morphology of the synthesized samples were analysed by various characterization techniques such as X-Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), UV-Vis Spectroscopy, and High-Resolution Transmission Electron Microscopy (HR-TEM), Brunauer-Emmett-Teller (BET) surface area analysis, Barrett-Joyner-Halenda (BJH) pore size analysis and Raman Spectroscopy. The efficiency of the prepared samples for removing hexavalent chromium from the water was investigated by performing batch adsorption studies. The maximum adsorption capacity was optimum at using 6 mg adsorbent, under conditions pH 2 with contact time for 120 min and temperature 283 K. Two isotherm models and two kinetic models were used to study the adsorption mechanism of Cr(VI) ions adsorption on the surface of GO/ZM nanocomposite. The results of isotherm and kinetic modelling shows that the adsorption of Cr(VI) using GO/ZM nanocomposite was well described by Freundlich Isotherm model with higher correlation coefficient (R2 = .985) and follows pseudo second order kinetic model.

Fabrication of Superhydrophobic Surface on Anodized Aluminum Through a Wet-Chemical Route

Fabrication of superhydrophobic surfaces on anodized aluminum substrates by wet-chemical grafting using cost-effective chemicals through a simple immersion process is described in this work. Formation of formate-alumoxane is possible by treating the anodized and sealed aluminum substrate with formic acid at around 50 °C. On treatment with sodium salts of higher-order carboxylic acids (stearic acid, lauric acid, and palmitic acid), the formate ions are replaced by higher-order carboxylates. A possible bonding mechanism of the longer chain carboxylic acids with aluminium surfaces has been suggested based on IRRAS and XPS studies. The as-prepared superhydrophobic aluminum substrates exhibited a static water contact angle of up to 167° with a sliding angle not higher than 6°, with decent resistance against abrasion in addition to good UV, environmental and thermal stabilities. Aluminium substrates of any size, shape and surface finish can be easily rendered robust and superhydrophobic without the use of expensive chemicals and sophisticated machinery.

A facile electrochemical lithiation method to prepare porous nickel oxide electrodes with high electrochromic performance

A facile electrochemical lithiation method was developed in the framework of the wet chemical route, and NiO films with various lithium contents have been successfully prepared. The structure and electrochromic properties were characterized using SEM, HRTEM, XRD, XPS, etc. The results indicate that all NiO films show a porous morphology, and the ratio of Ni3+/Ni2+ increases from 1.12 to 1.46 after electrochemical lithiation. The storage capacity in lithium electrolytes, effective ionic diffusion rate, transmittance modulation, and coloring efficiency are effectively improved. The optimized NiO electrode exhibits an excellent storage capacity of 6.4 mC/cm2 and transmittance modulation at 550 nm of 35.7%, compared to the pristine NiO (Q = 4.4 mC/cm2, ΔT = 24.3%). Two electrochromic devices were respectively assembled with the pristine and lithiated NiO electrodes as the anodic electrochromic layer. The latter exhibits higher transmittance modulation and coloring efficiency, proving that the electrochemical lithiation method is an effective way to prepare high-performance electrochromic devices.

Square-Facet Nanobar MOF-Derived Co3O4@Co/N-doped CNT Core-Shell-based Nanocomposites as Cathode Materials for High-Performance Supercapacitor Studies.

The binary as well as ternary nanocomposites of the square-facet nanobar Co-MOF-derived Co3O4@Co/N-CNTs (N-CNTs: nitrogen-doped carbon nanotubes) with Ag NPs and rGO have been synthesized via an easy wet chemical route, and their supercapacitor behavior was then studied. At a controlled pH of the precursor solution, square-facet nanobars of Co-MOF were first synthesized by the solvothermal method and then pyrolyzed under a controlled nitrogen atmosphere to get a core-shell system of Co3O4@Co/N-CNTs. In the second step, different compositions of Co3O4@Co/N-CNT core-shell structures were formed by an ex-situ method with Ag NPs and rGO moieties. Among several bare, binary, and ternary compositions tested in 6 M aqueous KOH electrolyte, a ternary nanocomposite having a 7.0:1.5:1.5 stoichiometric ratio of Co3O4@Co/N-CNT, Ag NPs, and rGO, respectively, reported the highest specific capacitance (3393.8 F g-1 at 5 mV s-1). The optimized nanocomposite showed the energy density, power density, and Coulombic efficiency of 74.1 W h.kg-1, 443.7 W.kg-1, and 101.3%, respectively, with excellent electrochemical stability. After testing an asymmetrical supercapacitor with a Co3O4@Co/N-CNT/Ag NPs/rGO/nickel foam cathode and an activated carbon/nickel foam anode, it showed 4.9 W h.kg-1 of energy density and 5000.0 W.kg-1 of power density.

Effect of Fe3+ and/or PO43– Doping on the Electrochemical Performance of LiNi0.5Mn1.5O4 Cathode Material for Li-Ion Batteries

An Fe3+/PO43– codoped LiNi0.5Mn1.4667Fe0.02P0.0133O4 sample has been prepared by a coprecipitation–hydrothermal method followed by two-step calcination. A novel wet chemical route, using FeSO4 rather than Fe2(SO4)3 as the Fe3+ source and NaH2PO4 as the PO43– source, is adopted to obtain uniform codoping of Fe3+ and PO43– ions in a carbonate precursor according to the precipitation–dissolution–transformation mechanism. For comparison, Fe3+-doped and PO43–-doped samples have been also synthesized via the same route. The effects of Fe3+/PO43– codoping and single doping on the crystalline structure, morphology, and electrochemical performance of LiNi0.5Mn1.5O4 are investigated. Compared with pristine and single doped samples, the codoped sample shows better electrochemical performance, with a specific discharge capacity of 125.2 mAh g–1 at 10 C and a capacity retention rate of 85.9% after 200 cycles at 1 C, under the synergy of Fe3+/PO43– codoping, including enhanced crystallinity, decreased Mn3+ content, significantly reduced primary particle size and secondary agglomeration, as well as the appearance of (110) surfaces in truncated octahedral primary particles.

Surface-functionalized boron nanosheets and their assembled suprastructures with unprecedented proton-transport properties.

Two-dimensional (2D) boron nanomaterials have received considerable attention due to their distinct physicochemical properties in contrast to bulk boron. However, the susceptibility to oxidation in air has limited their practical applications. In this study, we synthesize an environmentally stable bifunctionalized boron nanosheet via a wet chemical route. By lyophilization, we have hierarchically assembled the boron nanosheets into various well-ordered macroscopic forms, which exhibit unique structural features, such as stacking-induced nanochannels for proton transport. The resulting suprastructures show exceptionally high proton conductivity (∼90 mS cm-1 at 85 °C) and humidity sensitivity (response >40 000% at 97% RH). These findings demonstrate the immense potential of boron nanomaterials in electrochemical applications.

Application of ZnO-NRs@Ni-foam substrate for electrochemical fingerprint of arsenic detection in water.

Arsenic (As3+) is the most carcinogenic and abundantly available heavy metal present in the environment. Vertically aligned ZnO nanorod (ZnO-NR) growth was achieved on metallic nickel foam substrate via a wet chemical route and it was used as an electrochemical sensor towards As(iii) detection in polluted water. Crystal structure confirmation, surface morphology observation and elemental analysis of ZnO-NRs were conducted using X-ray diffraction, field-emission scanning electron microscopy and energy-dispersive X-ray spectroscopy, respectively. Electrochemical sensing performance of ZnO-NRs@Ni-foam electrode/substrate was investigated via linear sweep voltammetry, cyclic voltammetry and electrochemical impedance spectroscopy in a carbonate buffer solution of pH = 9 and at different As(iii) molar concentrations in solution. Under optimum conditions, the anodic peak current was found proportional to the arsenite concentration from 0.1 μM to 1.0 μM. The achieved values for limit of detection and limit of quantification were 0.046 ppm and 0.14 ppm, respectively, which are far lower than the recommended limits for As(iii) detection in drinking water as suggested by the World Health Organization. This suggests that ZnO-NRs@Ni-foam electrode/substrate can be effectively utilized in terms of its electrocatalytic activity towards As3+ detection in drinking water.

Investigation of conduction mechanism and UV light response of vertically grown ZnO nanorods on an interdigitated electrode substrate.

Vertically aligned zinc oxide nanorod (ZnO-NR) growth was achieved through a wet chemical route over a comb-shaped working area of an interdigitated Ag-Pd alloy signal electrode. Field-emission scanning electron microscopy images confirmed the formation of homogeneous ZnO-NRs grown uniformly over the working area. X-ray diffraction revealed single-phase formation of ZnO-NRs, further confirmed by energy-dispersive X-ray spectroscopy analysis. Temperature-dependent impedance and modulus formalisms showed semiconductor-type behavior of ZnO-NRs. Two electro-active regions i.e., grain and grain boundary, were investigated which have activation energy ∼0.11 eV and ∼0.17 eV, respectively. The conduction mechanism was investigated in both regions using temperature-dependent AC conductivity analysis. In the low-frequency dispersion region, the dominant conduction is due to small polarons, which is attributed to the grain boundary response. At the same time, the correlated barrier hopping mechanism is a possible conduction mechanism in the high dispersion region attributed to the bulk/grain response. Moreover, substantial photoconductivity under UV light illumination was achieved which can be attributed to the high surface-to-volume ratio of zinc oxide nanorods as they provide high density of trap states which causes an increase in the carrier injection and movement leading to persistent photoconductivity. This photoconductivity was also facilitated by the frequency sweep applied to the sample which suggests the investigated ZnO nanorods based IDE devices can be useful for the application of efficient UV detectors. Experimental values of field lowering coefficient (βexp) matched well with the theoretical value of βS which suggests that the possible operating conduction mechanism in ZnO nanorods is Schottky type. I-V characteristics showed that the significantly high photoconductivity of ZnO-NRs as a result of UV light illumination is owing to the increase in number of free charge carriers as a result of generation of electron-hole pairs by absorption of UV light photons.

Rapid controllable synthesis of branched Au superparticles: formation mechanism of toggling the growth mode and their applications in optical broadband absorption.

We develop a tunable, ultrafast (5 seconds), and mass-producible seed-mediated synthesis method to prepare branched Au superparticles consisting of multiple small Au island-like nanoparticles by a wet chemical route. We reveal and confirm the toggling formation mechanism of Au superparticles between the Frank-van der Merwe (FM) growth mode and the Volmer-Weber (VW) growth mode. The key factor of this special structure is the frequent toggling between the FM (layer by layer) growth mode and the VW (island) growth mode induced by 3-aminophenol, which is continuously absorbed on the surface of newborn Au nanoparticles, leading to a relatively high surface energy during the overall synthesis process, thus achieving an island on island growth. Such Au superparticles demonstrate broadband absorption from visible to near-infrared regions due to their multiple plasmonic coupling and hence they have important applications in sensors, photothermal conversion and therapy, etc. We also exhibit the excellent properties of Au superparticles with different morphologies, such as NIR-II photothermal conversion and therapy and SERS detection. The photothermal conversion efficiency under 1064 nm laser irradiation was calculated to be as high as 62.6% and they exhibit robust photothermal therapy efficiency. This work provides insight into the growth mechanism of plasmonic superparticles and develops a broadband absorption material for highly efficient optical applications.

Influence of Cu induced crystallographic disorder on the optical and lattice vibrational properties of ZnO nanoparticles.

In this study, the vibrational and optical responses of 0-10% excess Cu incorporated ZnO nanoparticles (NPs) prepared by the low temperature (∼400 °C) wet chemical route were investigated experimentally and were found to be predominantly linked to the formation of both intrinsic and Cu induced crystallographic defects instead of substitutional Cu itself for the first time. For low temperature chemical synthesis, the effective band gap (Eg) of pristine ZnO NPs was found to be as low as 2.84 eV, which was followed by a further reduction by as high as ∼24.4% with gradual Cu inclusion. Excess Cu incorporation was found to drastically restrict the particle growth phenomenon by ∼61% and alter the shape morphology from anisotropic to irregular isotropic. Although all NPs showed a single phase structure with hexagonal P63mc symmetry, the X-ray peak profile analysis along with the characteristic E2(High) Raman peak and electron-phonon coupling strength obtained from the 2nd order Raman mode suggested the presence of appreciable crystallographic disorders pertaining to point defects like Cu induced Zn and O interstitials and vacancies. Optical analysis revealed a gradual increase in Urbach tailing (Eu) from 0.35 to 0.96 eV directly associated with both intrinsic and Cu induced disorders arising from successive Cu incorporation at low processing temperature. A correlation between Eg and Eu predicted a direct-type band-to-band transition energy of ∼3.2 eV for the pristine ZnO crystal, suggesting both intrinsic and excess Cu induced extrinsic disorders to be the primary source of optical modulation of the NPs for the low temperature processing condition.

Facile aqueous synthesis of hollow dual plasmonic hetero-nanostructures with tunable optical responses through nanoscale Kirkendall effects.

Herein, we report the colloidal synthesis of hollow dual-plasmonic nanoparticles (NPs) using Au@Cu2O core-shell NPs as templates and exploiting the nanoscale Kirkendall effect. In our synthesis, we used organic compounds as a source of chalcogenide ions for an anion exchange reaction at elevated temperatures using polyvinylpyrrolidone (PVP) as a capping reagent to transform the solid Cu2O shell into a hollow copper chalcogenide shell. The resulting structures possess different features depending on the chalcogenide precursor employed. TEM images confirm the complete transformation of Au@Cu2O templates when 1,1-dimethyl-2-selenourea was added and the formation of hollow Au@Cu2-x Se nanostructures. In contrast, residues of Cu2O attached to the Au core were present when thioacetamide was used for the synthesis of Au@Cu2-x S with all other conditions kept the same. The divergence of architectures caused distinct optical properties of Au@Cu2-x S and Au@Cu2-x Se NPs. This synthetic approach is an effective pathway for maneuvering the size of interior voids by varying the concentration of chalcogenide ions in the reaction mixture. The insights gained from this work will enrich the synthetic toolbox at the nanoscale and guide us on the rational design of multicomponent plasmonic nanoparticles with precisely controlled hollow interiors and sophisticated geometries, further enhancing our capabilities to fine-tune the electronic, optical, compositional, and physicochemical properties.

Analytical probing of membranotropic effects of antimicrobial copper nanoparticles on lipid vesicles as membrane models.

Copper nanoparticles (CuNPs) are antimicrobial agents that are increasingly being used in several real-life goods. However, concerns are arising about their potential toxicity and thus, appropriate legislation is being issued in various countries. In vitro exploration of the permeability and the distribution of nanoparticles in cell membranes should be explored as the first step towards the investigation of the toxicity mechanisms of metal nanoantimicrobials. In this work, phosphatidylcholine-based large unilamellar vesicles have been explored as mimics of cellular membranes to investigate the effect of ultra-small CuNPs on the physicochemical features of phospholipid membranes. 4 nm-sized CuNPs were synthesized by a wet-chemical route that involves glutathione as a stabilizer, with further characterization by UV-vis absorption spectroscopy, fluorescence spectroscopy, transmission electron microscopy, X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared (FTIR) spectroscopy. Two fluorescent membrane probes bearing naphthalene moieties (laurdan and prodan) were used to monitor the bilayer structure and dynamics, as well as to demonstrate the strong membranotropic effects of CuNPs. The fluorescence spectroscopic studies were supported by dynamic light scattering (DLS) measurements and the calcein leakage assay. Additionally, the degree of perturbation of the phospholipid bilayer by CuNPs was compared against that of Cu2+ ions, the latter resulting in negligible effects. The findings suggested that CuNPs are able to damage the phospholipid membranes, leading to their agglomeration or disruption.

Brushite mineralised Scots pine (Pinus sylvestris L.) sapwood - revealing mineral crystallization within a wood matrix by in situ XRD.

Dicalcium phosphate dihydrate (CaHPO4·2H2O, DCPD, brushite) crystals were synthesised within Scots pine sapwood via a wet-chemistry route from aqueous solutions of Ca(CH3COO)2 and NH4H2PO4 salts. SEM/EDS analysis was used to assess the saturation of the wood cell lumina and cell wall as well as morphological features and elemental composition of the co-precipitated mineral. Brushite mineral crystallization and crystallite growth within the wood matrix was studied by in situ XRD. The chemical composition of the mineral before and after the dissolution was evaluated using FTIR spectroscopy. The overall impact of brushite on the thermal behaviour of wood was studied by TGA/DSC and TGA/DTA/MS analysis under oxidative and pyrolytic conditions. Bending and compression strength perpendicular and parallel to the fibre directions as well as bending strengths in longitudinal and transverse directions of the mineralised wood were also evaluated. Results indicate the viability of the wet-chemistry processing route for wood reinforcement with crystalline calcium phosphate (CaP)-based minerals, and imply a potential in producing hybrid bio-based materials that could be attractive in the construction sector as an environmentally friendly building material.

Aluminium Doped Cerium Oxide as an Efficient Nanophotocatalyst for the Elimination of Rhodamine B Dye Present in Water

The photodegradation efficiency of rhodamine B (RhB) dye present in water using aluminium-doped CeO2 (Ce1-xAlxO2-δ; x = 0, 0.1, 0.2, 0.3, 0.4 and 0.5) nanoparticles was studied in this work. The synthesis of nanoparticles was done by simple wet chemical precipitation route. The photochemical characteristics of Al doped CeO2 was studied by UV-visible (UV) and photoluminescence (PL) techniques. The photocatalytic removal of RhB dye was studied using the above nanomaterials as photocatalysts and the degradation efficiency was optimized by varying the pH and the concentration of dye solution under UV light. Among the samples studied, 0.02 g of sample with the composition of Ce0.50Al0.50O2- δ exhibited a higher photocatalytic degradation efficiency of 70.94% against RhB dye having concentration of 0.05 g/L at the pH of 11 under UV irradiation for 60 min at room temperature.

Design and photovoltaic studies of W@TiO2/rGO nanocomposites with polymer gel electrolyte

Designing the tungsten(vi) ion-doped TiO2/rGO nanocomposites (TR NCs) via a single-step in situ wet chemical route for Co2+/Co3+-based PEO–PEG polymer gel electrolyte-assisted D–π–A carbazole dye (SK3) sensitized solar cells (DSSCs).

Wet chemical synthesis of TGA capped Ag2S nanoparticles and their use for fluorescence imaging and temperature sensing in living cells.

In this work, we describe a simple wet chemical route for preparing silver sulfide nanoparticles (Ag2S) encapsulated with thioglycolic acid (TGA). By using Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), energy dispersive X-ray (EDS) microanalysis, transmission electron microscopy (TEM), and dynamic light scattering (DLS), we have found that these nanoparticles were enrobed by TGA molecules and they have an Ag/S ratio nearly equal to 2.2 and a nearly spherical shape with two average size populations. Photoluminescence (PL) spectroscopy has shown that these nanoparticles are highly luminescent, photostable and photobleaching resistant and they emit in the first biologic window with a band peaking in the NIR region at 915 nm. We have demonstrated through a 3-(4,5-dimethyl-thiazol-2yl)-2,5-diphenyltetrazolium bromide (MTT) assay protocol and using U-87 MG human living cells that these nanoparticles are biocompatible with a viability ratio higher than 80% for a concentration equal to 100 μg mL-1. By investigating the effect of pH, ionic strength and thermal quenching on the PL emission, we have shown that these nanoparticles provide a convenient stable tool to measure temperature in the biological range with a relative thermal sensitivity higher than 5% per °C and they may be used as suitable fluorescent probes for living cell imaging and intracellular temperature mapping.

Rapid Degradation of Methyl Orange by Heterogeneous Fenton Process Using Fewo4 Nanocatalyst Prepared by Wet Chemical Route.

To remove the hazardous organic adulterants from the wastewater, iron tungstate nanoparticles were prepared by a simple wet chemical route. These nanoparticles characterized to be polydispersed, polycrystalline with irregular spherical morphologies without any notable impurities were used as a catalyst for heterogeneous Fenton reaction, an advanced oxidation process. Their catalytic properties, degradation efficiency, and recyclability were analyzed for methyl orange degradation, a common -reactive azo dye in an acidic aqueous. The rapid fall of absorption peak exhibits the complete degradation of dye within 50 minutes of reaction with discoloration efficiency of ~97% without any additional external exposures such as light or ultrasonic waves. In addition to this, the durability of the FeWO4 nanoparticles catalyst is proved to be maintained over five catalyst reuse cycles, which strongly suggests that at this present scenario of ecological deterioration, the chosen nanomaterial is one of the apt candidates for azo dye removal by heterogeneous dark Fenton process.