Photocatalytic Studies Research Articles

Photostable selenium-assisted ZnS nanocomposite with efficient visible light photocatalytic activity

Selenium-assisted ZnS nanocomposite has been successfully prepared through a simple soft chemical route and their photocatalytic activity was also investigated for degradation of methylene and rhodamine B dye under ultraviolet and sunlight irradiation. Various surface analysis techniques such as XRD, SEM, TEM, UV-visible, XPS, and photoluminescence were used to analyze the formation of Se/ZnS nanocomposites. XRD studies confirmed the formation of the selenium phase along with ZnS and zinc methacrylate. SEM images showed that ZnS and Se nanoparticles self-aggregated to form three-dimensional spherical nano-assemblies of an average size of about 527 nm. The presence of a different type of defect in Se/ZnS was analyzed from PL spectra. The photocatalytic study revealed the complete degradation of methylene blue in 75 min with a rate constant of 0.073 min−1 under UV light irradiation. In contrast, rhodamine B (RhB) degraded in 90 min with a corresponding rate constant of 0.038 min−1 under the same time duration. Further, this nanocomposite was also efficient under natural sunlight, and almost 85% degradation was achieved after 180 min. Thus, the synergistic effect of strong absorption under UV and visible light source of Se/ZnS nanocomposite minimizes the photogenerated electron-hole pair recombination., which makes them excellent photocatalysts towards the degradation of dyes. Also, this nanocomposite reduced the photo-corrosion under light irradiation and improved photocatalytic stability. In addition, scavenger studies and electron spin resonance in combination with spin trapping technique were used to analyze the contribution of reactive species involved in photocatalysis process.

In Situ UV-Vis-NIR Absorption Spectroscopy and Catalysis.

This review highlights in situ UV-vis-NIR range absorption spectroscopy in catalysis. A variety of experimental techniques identifying reaction mechanisms, kinetics, and structural properties are discussed. Stopped flow techniques, use of laser pulses, and use of experimental perturbations are demonstrated for in situ studies of enzymatic, homogeneous, heterogeneous, and photocatalysis. They access different time scales and are applicable to different reaction systems and catalyst types. In photocatalysis, femto- and nanosecond resolved measurements through transient absorption are discussed for tracking excited states. UV-vis-NIR absorption spectroscopies for structural characterization are demonstrated especially for Cu and Fe exchanged zeolites and metalloenzymes. This requires combining different spectroscopies. Combining magnetic circular dichroism and resonance Raman spectroscopy is especially powerful. A multitude of phenomena can be tracked on transition metal catalysts on various supports, including changes in oxidation state, adsorptions, reactions, support interactions, surface plasmon resonances, and band gaps. Measurements of oxidation states, oxygen vacancies, and band gaps are shown on heterogeneous catalysts, especially for electrocatalysis. UV-vis-NIR absorption is burdened by broad absorption bands. Advanced analysis techniques enable the tracking of coking reactions on acid zeolites despite convoluted spectra. The value of UV-vis-NIR absorption spectroscopy to catalyst characterization and mechanistic investigation is clear but could be expanded.

Synergistic potential in spinel ferrite MFe2O4 (M = Co, Ni) nanoparticles-mediated graphene oxide: Structural aspects, photocatalytic, and kinetic studies

The existence of artificial dyes in water is a significant environmental concern, as it can lead to poor water quality. Photodegradation is becoming an increasingly popular method for treating water contaminated with dyes. In this study, the photodegradation of Reactive Red 66 and Reactive Red 120 dyes, as well as textile wastewater, was investigated under UV and visible light irradiation. To enhance the photoresponse of the MFe2O4 (M = Co, Ni) nanoparticles, modifications were made by incorporating graphene oxide. The MFe2O4 nanoparticles and MFe2O4/GO nanocomposite photocatalysts were subjected to several characterization techniques, including FT-IR, Raman spectroscopy, XRD, DRS, zeta potential, VSM, TGA, DSC, BET, SEM, and EDAX analysis. Experiments were conducted to optimize several key parameters involved in the photodegradation process, including pH, photocatalyst dosage, initial dye concentration, and irradiation time. The removal efficiency of Reactive Red 66 and Reactive Red 120 dyes using CoFe2O4 nanoparticles was found to be 86.97 and 82.63%, respectively. Also, the removal percentage of these dyes using CoFe2O4/GO nanocomposite photocatalyst was 95.57 and 90.9% for Reactive Red 66 and Reactive Red 120, respectively. Experiments found that NiFe2O4 nanoparticles removed 90.92% of Reactive Red 66 dye and 84.7% of Reactive Red 120 dye. The NiFe2O4/GO nanocomposite photocatalyst showed even higher removal efficiencies, degrading 97.96% of Reactive Red 66 and 93.44% of Reactive Red 120. After three days of exposure to visible light irradiation, the removal percentage of Reactive Red 66 using MFe2O4 and MFe2O4/GO nanocomposite was investigated.

Investigations on Chemically Synthesized Pure and Doped Manganese Dioxide Nanoparticles for Dye Removal and Photocatalytic Applications.

Pure and Mg2+, Ni2+, Cd2+ doped MnO2 nanoparticles were synthesized by chemical co-precipitation method. These samples were characterised by PXRD, SEM, EDX, FTIR, UV-Vis-NIR, PL, Antibacterial, Cyclic Voltammetry, Dye Degradation and Photocatalytic studies. From the powder XRD studies, the crystallite size of the particle was calculated using Scherer formula and found that the synthesized nanoparticles were in the range from 10 to 12nm. The morphology of all the synthesized samples was viewed from SEM micrograph. The composition and purity of the samples were identified from EDX studies. In FTIR spectra metal-oxygen stretching and bending modes of vibrations were observed. From the absorption spectra of UV-Vis optical analysis values of absorption coefficient, extinction coefficient, refractive index, real and imaginary part of optical dielectric constant and optical conductivity were compared. The band gap energy obtained from Tauc's plot varies from 1.21 to 1.51eV exhibits semiconducting behaviour of all the synthesized samples. Investigations on photoluminecsence spectrum reveals blue shift in wavelength for doped nanooxides compared to pure MnO2. Antimicrobial activity of synthesised samples against gram positive and gram negative bacteria was determined. The obtained results reveal very high bacterial resistance in Cd2+ doped MnO2 nanoparticles with higher activity towards bacterial resistance compared to standard drug. The specific capacitance values were determined from Cyclic Voltammetry studies. Using the batch method of dye removing technique the percentage of malachite green dye removal was calculated. Also the photocatalytic efficiency of all the synthesized MnO2 samples in removing malachite green dye was studied by exposing to sunlight for different dosage and contact time. Ni2+ doped MnO2 shows relatively higher % of dye degradation capacity about 93% for 0.1g of dosage of photocatalysts.

Application of natural solar photocatalytic and DSSC's studies AC loaded on Ag–In2O3 nanoparticles by hydrothermal approach

Contaminants are repeatedly being released into the land, water and air about the world as a consequence of the high levels of human movement and development, which causes a fast an increase in the growing of pollution. In this assessment, activated charcoals supported on Ag–In2O3 nanomaterials were blended by hydrothermal system. The morphology constitution, surface assets and optical description of synthesized nanomaterials were characterized by XRD, UV-DRS, PL, HR-SEM and EDAX, HR-TEM, SAED pattern, FT-IR, XPS, BET, CV and VSM techniques. The optimized heterogeneous catalyst AC/Ag–In2O3 depicts high electro catalytic activity, fast-charge transport development, weak ferromagnetism, brilliant accessibility and stability for Rh6G dye degradation, which is endowed for application in the alkaline medium. The prepared photocatalytic activity towards AC/Ag–In2O3 have been revealed as the degradation of Rhodamine 6G (Rh6G) dye in the presence of aqueous solution directed to solar light irradiation. AC/Ag–In2O3 is initiated to maintain some more efficient than synthesized Ag–In2O3 and In2O3 by pH9 positively mineralizing of Rh6G dye under sun light irradiation. The mineralization of Rh6G dye has been confirmed by measuring COD analysis. It is suggested that Rh6G degrades in the presence of solar light via a particular mechanism, which was discovered that the catalyst remained more stable and reusable. It has been effectively determined that the AC/Ag–In2O3 nanomaterial achieves photocatalytic effects.

Separation of TiO2 and Fe2O3 from Indonesia Ilmenite Minerals and their Application as Photocatalysts for Eriochrome Black‐T Dye Degradation

AbstractAnatase‐TiO2 and α‐Fe2O3 were successfully separated from Indonesia ilmenite minerals using a modification of the hydrometallurgy process. Sodium salt was used as an initiated roasting before hydrochloric leaching. The study investigated parameters that affect separation such as mass ratios of sodium salt to ilmenite and leaching temperature. The results revealed that Ti composition in residue‐TiO2 increased to 76 % while Fe‐composition in filtrate‐Fe2O3 was 87 %. The XRD diffractogram analysis confirmed that main phase formed in residue of separation was anatase‐TiO2 whereas in hydrolysed of filtrate from separation was hematite. Both residue‐TiO2 and filtrate Fe2O3 had high thermal stability. The photocatalytic activity of anatase‐TiO2 and α‐Fe2O3 showed about 97 % and 85 % of Eriochrome Black‐T dye solution was degraded, respectively, when conducted to 4 hours of UV light irradiation. Photocatalytic kinetics study of anatase‐TiO2 and α‐Fe2O3 in degradation process followed pseudo‐first order with reaction rate at 0.0144 and 0.0070 min−1, respectively.

Biotemplated silicon carbide-loaded ytterbium oxide: Effective catalyst for photocatalytic hydrogen evolution reactions

SiC-doped Yb2O3 structure (Yb2O3/SiC) was prepared to enhance the photocatalytic hydrogen evolution performance of Yb2O3 nanofiber, which have been performed by using catalyst in the presence of eosin-Y dye and triethanolamine, called photosensitizer and electron donor, respectively under solar light with/out cellulose and chitosan. In this study, cellulose and chitosan were used as biotemplates to increase the hydrogen production of Yb2O3/SiC nanofibrous catalyst in the photocatalytic hydrogen evolution reaction. Bioorganic-inorganic structures, cellulose-Yb2O3/SiC and chitosan-Yb2O3/SiC, were obtained by simply adding cellulose and chitosan to the reaction cell without any additional treatment. Cellulose and chitosan also used as a mediator for dispersion, hydrophilicity, morphological transformation and adhesion to semiconductor with the help of functional groups. The hydrogen production rate of bare SiC, bare Yb2O3, Yb2O3/SiC composite have been measured as 391 μmol g−1, 818 μmol g−1 and 1685 μmol g−1, respectively. Moreover, the hydrogen production rate of cellulose-Yb2O3/SiC and chitosan-Yb2O3/SiC composites were came up to 3346 μmol g−1, 4084 μmol g−1, respectively. These results have been showed that the Yb2O3/SiC nanofibrous catalyst showed higher activity in the presence of cellulose and chitosan. The existence of biopolymers will create a new field in photocatalytic hydrogen production studies with the advantages mentioned above, thanks to the functional groups.

Hydrothermal synthesis of zinc molybdates (α-ZnMoO4) nanoparticles and its applications of supercapacitor and photocatalytic performances

Abstract The rational construction and design of nanostructured materials have a significant impact on the fabrication of high-performance electrode materials, which have attracted considerable interest in an effort to enhance the reliability and efficiency of energy storage devices. In this study, the α-ZnMoO4 nanoparticles were successfully prepared by facile hydrothermal method and the influence of various hydrothermal reaction times on structural, morphological, optical and electrochemical properties were studied. XRD analysis illustrated that α-ZnMoO4 nanoparticles exhibited anorthic crystal structure and the average crystallite size was 42 nm. FESEM images changed from a cubic structure to plate-like structures depending on reaction times. HRTEM analysis revealed that prepared sample showed a plate-like structure and the SAED pattern exhibited a polycrystalline nature. The FTIR spectrum confirmed the presence of vibrational molecules in α-ZnMoO4 nanoparticles. The BET and XPS measurements showed the α-ZnMoO4 nanoparticles were mesoporous and had Zn2+ and Mo6+ oxidation states, respectively. From UV–Visible spectra, a better spectral selectivity region was observed at higher reaction times, and the bandgap values were decreased from 2.73 to 2.48 eV. In photocatalytic studies, RhB dye was used as an organic pollutant and achieved a degradation efficiency of 85 % at an optimized reaction time of 24 h. For electrochemical performances, the prepared electrode material showed maximum specific capacitance values of 165 F g−1 and 110 F g−1 for cyclic voltammetry and galvanoststic charge-discharge analysis, respectively.

Photoluminescence and photocatalytic degradation studies of Zn-based nanoparticles on malachite green dye

Water, the most fundamental source of life, is contaminated by various organic pollutants, especially organic dyes from the dying industry. The photocatalytic degradation of malachite green (MG) was studied using a zinc-based metal-organic framework (Zn-BTC MOF) and ZnO. Thermally decomposing Zn-MOF synthesized ZnO and its structural and optical properties were analyzed using various spectroscopic techniques. This article focuses primarily on the wavelength-dependent photoluminescence properties of Zn-MOF and ZnO materials and their role in the photocatalytic degradation of MG dye in water. Zn-MOF and ZnO photocatalysts exhibited a photodegradation efficiency of approximately 99% after 40 min of visible light exposure. Based on kinetic experiments, the degrading efficiency of these catalysts followed pseudo-first-order reaction kinetics with a correlation of R2 = 0.99 and a rate constant of 0.031 min−1. This manuscript is helpful to researchers working on ZnO and Zn-MOF materials for photocatalytic and environmental applications.

3D-Cobalt-Dicyanamide-Derived 2D-Layered-Co(OH)2-Based Catalyst for Light-Driven Hydrogen Evolution.

Derivation of 3D coordination polymers to produce active catalysts has been a feasible strategy to achieve a precise coordination sphere for the catalytic site. This study demonstrates the partial conversion of a 3D cobalt dicyanamide coordination polymer, Co-dca, to a 2D layered hydroxide-oxyhydroxide structure under photocatalytic conditions. The catalyst exhibits an activity as high as 28.3 mmol h-1 g-1 in the presence of a [Ru(bpy)3]2+/triethylamine (TEA) couple to maintain it for at least 12 h. Photocatalytic and characterization studies reveal that the dicyanamide ligand within the coordination polymer is crucial for governing modification and achieving a superior H2 evolution rate. Moreover, we observed the critical role of TEA as the hydrolyzing agent for the transformation process. This study displays that the metal dicyanamides can be utilized as templates for preparing active and robust catalysts.

Photocatalytic Studies on Zinc Oxide Nanoparticles Doped with Selenium and Silicon Dioxides for Photodegradation of Lasix Drug

Metal oxide nanoparticles have taken a broad area of intense research because of their unique properties and application in diversified fields. Zinc oxide (ZnO) nanoparticles show varied morphologies and significant activities especially after doped with different metals. In this work, ZnO nanoparticles, Selenium dioxide (SeO2) doped Zinc oxide nanoparticles and Silicon dioxide (SiO2) doped Zinc oxide nanoparticles are synthesised by sol-gel method. The dopant effect on ZnO for band gap energy, crystal size and morphology are investigated by analysing the UV-DRS, powder X-ray diffraction and FESEM measurements respectively. The photocatalytic activities of these synthesised nanoparticles are compared by subjecting them into degradation of drug Lasix (furosemide) under UV and Solar irradiation sources. The progress of drug degradation is studied by measuring absorbance versus time interval at constant wavelength (325 nm) of the drug. The rate coefficient values found in this oxidative (H2O2) and reductive (NaBH4) catalytic degradation process of the drug is found efficient in solar irradiations. The results of characterisation studies and the order of photocatalytic activities of the nanoparticles are discussed.

Combination of ensemble machine learning models in photocatalytic studies using nano TiO2 - Lignin based biochar

Synergizing photocatalytic reactions with machine learning methods can effectively optimize and automate the remediation of pollutants. In this work, commercial Degussa TiO2 nanoparticles and lignin based biochar (LB) where used to prepare TiO2: lignin based biochar (TLB) composites using ultrasound-assisted co-precipitation method. The photocatalytic property of the TLB composites where studied by conducting the photocatalytic degradation of a Basic blue 41 (BB41) dye. The influence of calcination temperature, T:LB compositions, catalyst dosage, initial dye pH, initial dye concentration, and illumination time on photocatalytic dye degradation were experimentally studied. The degradation efficiency of 96.72 % was obtained under optimized conditions for the photocatalyst calcined at 500 °C containing a 1:1 wt percentage of TiO2 and LB. The experimental data was further used to predict the photocatalytic degradation efficiency using Gradient Tree Boosting (GTB) and Extra Trees (ET) models. The GTB model gave the highest prediction accuracy of 94 %. The permutation variable importance revealed catalyst dosage and dye concentration as the most influential parameters in the prediction of the photocatalytic dye degradation efficiency.

Ultrasound-assisted green synthesis of single phase Fe3O4 nanoparticles and its photocatalytic study for tetracycline photooxidation

Presently, Fe3O4 nanoparticles with high photocatalytic activity were prepared using the ultrasound-assisted green synthesis method using Tagetes erecta flower extract. A single phase Fe3O4 nanoparticles is well-recognized by physicochemical characterization utilizing x-ray diffraction (XRD), transmission electron microscopy (TEM), and x-ray photoelectron spectroscopy (XPS). Morphological study using scanning electron microscopy (SEM) on the material showed a flower-like shape of the nanoparticles. The particle’s size distribution analysis recognized a mean particle size of 29.9 nm. Further study using diffuse reflectance UV–Visible spectroscopy (UV-DRS) gave the band gap energy of 2.68 eV, and VSM analysis has revealed the purity of the nanoparticles that support its feature as magnetic separability as easy method for reusability. The features support the photocatalytic applications as the nanoparticles was demonstrated by fast removal of tetracycline at varied concentration (5–40 mg/L). The highest value of degradation efficiency was 99.9 % expressed by the treatment to 10 mg/L of tetracycline. Mechanistic studies of photooxidation including the effect of pH and photocatalyst stability, suggested the potency of synthesized Fe3O4 nanoparticles as low-cost method for environmental applications.

An Effective Strategy for the Photocatalytic Elimination of Industrial Wastewaters Via MgFe-LDH/TiO2 Heterojunctions

Reactive dyes are presently the most common type of dye utilised by the garment sector to colour wool, cotton, and viscose-based clothing. By using the typical biological degradation & sediment absorb approaches, it is quite impossible to get rid of them. Thus reactive dye colors in the effluent are major environmental issues in recent times. In this work Reactive dye series has been choosen for the photocatalytic degradation studies over calcined form of TiO2 and MgFe-LDHcal nanocomposites (TiO2/MgFe-LDHcal). This work assesses, a detailed investigation of the photocatalytic degradation of the reactive class dyes Ca. Reactive green 19, Reactive red 120, Reactive blue 4 and Eosin Yellowish dye by layered double hydroxide (LDH) and TiO2 heterojunction (MgFe-LDHcal/TiO2). Here for the first time, photocatalytic application of the said heterojunction was investigated toward the degradation of the reactive dyes. As these dyes are cytotoxic, mutagenic, and inhibit certain mitochondrial functions and often are carcinogens. This heterojunction system degrades the reactive dyes in 1 hour of visible light irradiation. The said LDH heterojunction was characterised by powder XRD to confirm the phase and composite formation, Uv-Visible and PL spectra to know the optical activity of the material in presence of light. The size, interplanar spacing and morphology of the nanoparticles were inspected by HR-TEM analysis. All the batch experiments were carried out at room temperature, without any adjustment of pH, at the dye concentration varying from 20 to 50 mg/L. Furthermore, according to the rejuvenation study, the prepared LDH heterojunction system could potentially be put to use for a number of cycles.

Optical and photocatalytic studies of the novel 2D penta-M4P4X2Y2 (M=Pd, Pt; X≠Y[dbnd]S, Se, Te) Janus monolayers

In this article we report novel penta-like M4P4X2Y2 (M = Pd, Pt; X≠YS, Se, Te) Janus monolayers. The structural stability of the monolayers is double checked by using the phonon spectra and AIMD simulations. After confirming the thermodynamic stability of the monolayers, their structural, mechanical, electronic, and optical properties are systematically explored using the density functional theory (DFT). The calculated results demonstrate indirect bandgap for these monolayers, ranging from 1.57 to 2.58 eV. Furthermore, the photocatalytic investigations show that M4P4X2Y2 Janus monolayers exhibit the capability of oxidizing H2O/O2 to O2, while reducing H+ to H2. These findings strongly indicate the potential of M4P4X2Y2 monolayers as photocatalysts for water splitting reaction.

A new BiOCl–ZnFe2O4/CNTs ternary composite for remarkable photocatalytic degradation studies of a herbicide and a diazo dye

Fabrication of binary or ternary nanocomposite of different semiconducting materials has received considerable attention for the development of an efficient, novel and realistic photocatalyst. Herein, we report the synthesis of BiOCl, spinel ZnFe2O4, BiOCl–ZnFe2O4 hybrid, and BiOCl–ZnFe2O4/CNTs ternary composite. Pure BiOCl and spinel ZnFe2O4 were synthesized by co-precipitation method while BiOCl–ZnFe2O4 hybrid and BiOCl–ZnFe2O4/CNTs ternary composite by an ultra-sonication approach. The prepared photocatalytic samples were scrutinized by X-ray diffraction (XRD) technique, Fourier transform infra-red (FTIR) spectroscopy, and UV–Visible (UV–Vis) spectroscopy. The calculated optical energy gaps of BiOCl and spinel ZnFe2O4 using Tauc equation were 3.21 eV and 2.19 eV respectively. The photocatalytic efficiency of all prepared photocatalysts was tested against a herbicide (Pendimethalin), and an anionic diazo dye (Congo red). The obtained results revealed that carbon nanotubes based ternary composite of BiOCl–ZnFe2O4 hybrid has high rate and percentage degradation for both pendimethalin and congo red among all synthesized materials. For pendimethalin removal, the value of rate constant of BiOCl–ZnFe2O4/CNTs is 0.01 min−1 and % degradation is 88.6 %. Moreover, BiOCl–ZnFe2O4/CNTs ternary composite exhibits 95.27 % degradation and rate constant of 0.02 min−1 for congo red dye. The higher photocatalytic removal activity of ternary composite (BiOCl–ZnFe2O4/CNTs) as compared to other fabricated photocatalysts is due to its high surface area, greater adsorption capability, high charge transfer rate and low e−/h+ pair recombination. Hence, BiOCl–ZnFe2O4/CNTs composite could be an efficient photocatalyst for the mineralization of various organic industrial effluents.

Revealing the impact of different precursors and solvents for supramolecular complex formation and in-situ C-doping in g-C3N4 with enhanced photocatalytic H2O2 production

The reinforced light-harvesting capability suppresses photocarrier recombination and increases the specific surface area, representing the possibility of excellent photocatalytic performance for graphitic carbon nitride (CN) photocatalysts. Herein, the remarkable photocatalytic properties of porous carbon-doped g-C3N4 (CCN) were enhanced through the incorporation of a supramolecular complex, M-CA-U (melamine-cyanuric acid-urea), in DMSO as the carbon dopant source. Through the diverse characterization methods, the successful formation of the supramolecular g-C3N4 using varying polarity of solvent was verified, achieved through a simple hydrothermal/solvothermal process. The CCN-MCAU-DMSO photocatalyst achieved the maximum photocatalytic H2O2 production rate, 1.3-fold higher than other prepared samples. The outstanding performances of CCN-MCAU-DMSO were probably attributed to the extended specific surface area, robust visible light response, adjusted electronic band structure, accelerated charge separation, and limited charge recombination. The photocurrent response and photoluminescence spectroscopy analysis confirmed excellent charge carriers and separation. Overall, this work provided a new idea to design and construct high-efficiency porous supramolecular assembly of CCN photocatalysts for photocatalytic studies.

Photocatalytic and antimicrobial studies of green synthesized Dy3+doped ZnO nanoparticles prepared from Rhododendron arboreum petal extract

In this study, the primary focus revolves around the synthesis of zinc oxide (ZnO) and dysprosium-doped zinc oxide (Dy-doped ZnO) nanoparticles utilizing a green chemistry approach, employing Rhododendron arboreum petal extract as a key component. A thorough characterization of nanoparticles has been carried out, involving a range of analytical techniques including UV–visible spectroscopy, Fourier-transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDX), high-resolution transmission electron microscopy (HRTEM), selected-area electron diffraction (SAED), and fluorescence emission spectroscopy. The structural examination confirmed the persistent hexagonal wurtzite structure of ZnO nanoparticles, which remained unaltered even with Dy doping. The XPS analysis corroborated the presence of lattice oxygen in addition to confirming the presence of Dy3+ and Zn2+. The results indicated that the incorporation of Dy3+ ions replaces Zn2+ ions in host ZnO leading to an increase in the defects inside ZnO. Based on HRTEM images, the particle size was determined to be 31 nm for ZnO nanoparticles and 39 nm for Dy-doped ZnO nanoparticles. FESEM imaging unveils a morphology reminiscent of pebbles, and EDX spectra provide additional evidence of the presence of Zn, Dy, and O elements within the nanoparticles, which aligns with the findings from XPS. Subsequently, these synthesized nanoparticles were harnessed for the remediation of novacron brown, a textile dye. Additionally, nanoparticles were explored for their antibacterial and antifungal properties which highlight the considerable potential of these nanoparticles in these specific domains.

Effect of Co Doping on the Physical Properties and Organic Pollutant Photodegradation Efficiency of ZnO Nanoparticles for Environmental Applications.

This paper presents a comprehensive investigation of the synthesis and characterization of Zn1-xCoxO (0 ≤ x ≤ 0.05) nanopowders using a chemical co-precipitation approach. The structural, morphological, and vibrational properties of the resulting ZnO nanostructures were assessed through X-ray diffraction, scanning electronic microscopy, and Raman spectroscopy to examine the influence of cobalt doping. Remarkably, a notable congruence between the experimental results and the density functional theory (DFT) calculations for the Co-doped ZnO system was achieved. Structural analysis revealed well-crystallized hexagonal wurtzite structures across all samples. The SEM images demonstrated the formation of spherical nanoparticles in all the samples. The vibrational properties confirmed the formation of a hexagonal wurtzite structure, with an additional Raman peak corresponding to the F2g vibrational mode characteristic of the secondary phase of ZnCo2O4 observed at a 5% cobalt doping concentration. Furthermore, a theoretical examination of cobalt doping's impact on the elastic properties of ZnO demonstrated enhanced mechanical behavior, which improves stability, recyclability, and photocatalytic activity. The photocatalytic study of the synthesized compositions for methylene blue (MB) dye degradation over 100 min of UV light irradiation demonstrated that Co doping significantly improves photocatalytic degradation. The material's prolonged lifetime, reduced rate of photogenerated charge carrier recombination, and increased surface area were identified as pivotal factors accelerating the degradation process. Notably, the photocatalyst with a Zn0.99Co0.01O composition exhibited exceptional efficiency compared to that reported in the literature. It demonstrated high removal activity, achieving an efficiency of about 97% in a shorter degradation time. This study underscores the structural and photocatalytic advancements in the ZnO system, particularly at lower cobalt doping concentrations (1%). The developed photocatalyst exhibits promise for environmental applications owing to its superior photocatalytic performance.

A thienothiophene and anthracene based functional hyperbranched polymer: synthesis, photophysical properties and photocatalytic studies

Conjugated polymer photocatalysts containing thienothiophene are emerging to be important in the field of photocatalytic hydrogen evolution, owing to their tunable molecular structures and electronic properties.