Photocatalytic Activity For Degradation Research Articles

Performance evaluation of Bi/Zn‐impregnated commercial TiO2 nanoparticles for photocatalytic nitrobenzene decomposition

AbstractBACKGROUNDCommercial TiO2 nanoparticles were subjected to modification through Bi and Zn metal doping. The resulting catalysts were comprehensively characterized, and their performance was then reviewed for removal of model pollutant nitrobenzene in water.RESULTSAmidst the synthesized catalysts, the co‐doping of Bi/Zn (0.25:0.75 wt%) demonstrated the best photocatalytic degradation activity, achieving 95% degradation within 90 min of reaction time, with 2.99 × 10−2 min−1 rate constant value. The involvement of different radicals during the degradation process was elucidated by employing appropriate radical scavengers. Furthermore, the degradation results were investigated applying the first‐order kinetic model, leading to the determination of reaction rate constants and initial rates of the degradation process.CONCLUSIONAn improved photocatalytic activity was observed with metal doping due to the synergistic effect of doped metals with commercial TiO2 and profound charge transfer among them. It was observed that performance was increased with temperature rise in the practical range of application, that is, 5–20 °C. This behavior was due to high rate of movement of charge carriers. Further, involvement and functioning of various radical species such as h+, OH− and O2− in nitrobenzene degradation were successfully established using appropriate radical scavengers. © 2024 Society of Chemical Industry (SCI).

Reduced Work Function in Anatase ⟨101⟩ TiO2 Films Self-Doped by O-Vacancy-Dependent Ti3+ Bonds Controlling the Photocatalytic Dye Degradation Performance.

TiO2 has the proven capability of catalytically decomposing pollutants under light illumination, thereby embracing potential applications in wastewater management. The photocatalytic dye degradation activity is largely controlled by the optical band gap that dictates the extent of electron-hole pair generation via photon absorption, and the recombination kinetics of charges. In this context, the material's work function governs how easily the charge carriers can be transferred at the dye-adsorbed photocatalytically active sites. Accordingly, nanocrystalline TiO2 thin films are grown in the anatase phase with ⟨101⟩ orientation, using RF magnetron sputtering at 200 °C. Besides studying the film's structural morphology, optical band gap, and elemental composition, the electronic properties are extensively investigated. The work function of the material was controlled by varying the O-vacancy-dependent Ti3+ bonding configuration in the network. It has been demonstrated how the photocatalytic methylene blue dye degradation activity of the nanocrystalline TiO2 films of predominantly the anatase phase improves on reducing the sputtering pressure during deposition. At a low deposition pressure of 20 mTorr, a low work function of ∼4.2 eV of the film, resulting from the formation of a Ti3+-bond through the O vacancies in the network, potentially increases its carrier lifetime and delivers the superior photocatalytic activity (∼82.7% dye degradation with a rate constant of k ∼ 0.0073 min-1) via silently facilitating fast electron transfer from the photocatalyst to the dye in the aqueous solution. The higher stoichiometric film prepared at p = 40 mTorr exhibits an inferior photocatalytic activity (∼20.4% dye degradation with a rate constant of k ∼ 0.0009 min-1), as retarded by its higher work function of ∼4.62 eV, despite retaining a relatively low band gap. Thus, without using any heterojunction or extrinsically doped photocatalyst, the dye degradation can be controlled simply by reducing the work function of nanocrystalline TiO2 thin films via controlling the O-vacancy-dependent Ti3+ bonding in its self-doped network.

Synthesis of Fe-doped ZnO/biochar nanocomposites for Acid Orange 7 photodegradation and antibacterial activity under visible light region

Abstract In the present study, different molar ratios of Fe-doped ZnO/biochar (FZBC) were synthesized using a coprecipitation method. ZnO nanoparticles with a size of approximately 30 nm were well dispersed on the biochar matrix. The bandgap energy decreases from 3.11 to 3.08 eV as the Fe-ion concentration increases from 1 to 7 mol%. Photocatalytic studies demonstrated that FZBC exhibited photodegradation toward acid orange 7 (AO7). FZBC exhibited a photodegradation efficiency of AO7 at a concentration of 10 mg. L-1 (93.17%), which was nine times greater than that of pure ZnO (10.30%). Furthermore, the FZBC materials also demonstrated effective inactivation of E. coli, with an antibacterial rate reaching 98%. Overall, these materials are expected to be cost-effective and suitable for photocatalytic degradation and antibacterial activities.

Unraveling the potential of heteroanionic titanium oxycarbide photocatalysts for detoxifying SARS-Cov-2 antigen rapid test kit reagent solution in water sources

In the last few years, the COVID-19 pandemic has increased the usage of antigen rapid test (ART) kits and improper disposal of these kits has led to the mixing of toxic chemical compounds present in the ART reagent solution container into drinking water sources. When consumed with drinking water, these compounds can be harmful and toxic to both humans and aquatic life. Therefore, this research presents a study on the photocatalytic degradation of the Antigen Rapid Test-Reagent solution (ART-RS) using a single-phase titanium oxycarbide - TiO0.25 C0.75 (TiOC) photocatalyst synthesized through a solid-state reaction. The synthesized samples were studied using various characterization tools to analyze their structural, morphological, and optical characteristics. In the photocatalytic experiment, it was found that the synthesized titanium oxycarbide photocatalyst exhibited superior ART-RS degradation efficiency of 77% compared to commercial titanium dioxide (22%). The improved photocatalytic degradation efficiency of ART-RS is attributed to a combination of several factors. These factors include a narrower band gap, more efficient charge transfer kinetics, enhanced absorption of visible light, and an upward shift of the valence band (VB) edge in titanium oxycarbide. These collective effects contribute to the enhanced ART-RS photocatalytic degradation activity.

Fabrication of black phosphorus/CdS heterostructure with enhancement photocatalytic degradation activity for tetrabromobisphenol A and toxicity prediction of intermediates

Black phosphorus nanosheets (BPNs)/CdS heterostructure was successfully synthesized via hydrothermal method. The experimental results indicated that BPNs modified the surface of CdS nanoparticles uniformly. Meanwhile, the BPNs/CdS heterostructure exhibited a distinguished high rate of photocatalytic activity for Tetrabromobisphenol A (TBBPA) degradation under visible light irradiation ( > 420 nm), the kinetic constant of TBBPA degradation reached 0.0261 min−1 was approximately 5.68 and 9.67 times higher than that of CdS and P25, respectively. Moreover, superoxide radical (•O2−) is the main active component in the degradation process of TBBPA (the relative contribution is 91.57%). The photocatalytic mechanism and intermediates of the TBBPA was clarified, and a suitable model and pathway for the degradation of TBBPA were proposed. The results indicated that the toxicities of some intermediates were higher than the parent pollutant. This research provided an efficient approach by a novel photocatalyst for the removal of TBBPA from wastewater, and the appraisal methods for the latent risks from the intermediates were reported in this paper.

Potential enhancements in the photocatalytic activity of the anatase 001 surface by adding cerium impurity

AbstractThis research investigates the structural and electronic properties of titanium dioxide ($$ TiO_2 $$ T i O 2 ) surfaces with the addition of cerium (Ce) impurities using first principles calculations within the framework of density functional theory, employing the pseudopotential method and the computational package Quantum ESPRESSO. Density of states (DOS) calculations reveal that the clean surface exhibits semiconductor behavior. In contrast, the titanium dioxide surface with Ce impurities on the fifth layer generates intermediate states within the energy band gap, resulting in a reduction in the band, with an intraband energy gap of 0.7882 eV induced. Moreover, the inclusion of a Ce atom on the fourth layer of the surface results it is observed that the surface an important characteristic is the appearance of intermediate states in the band gap, which are close to the valence band with a magnetic moment of 0.91 $$ \mu \beta /cell $$ μ β / c e l l . The ntraband gap can enhance the utilization of the visible spectrum. Additionally, the Ce impurity on the $$ TiO_2 $$ T i O 2 surface could promote greater photocatalytic activity in pollutant degradation and increase the oxidative capacity of titanium dioxide.

Controlled preparation of bamboo charcoal/BiOCl with efficient visible-light-driven photocatalytic activity for organic pollutant degradation using the residues of bamboo processing

In this research, bamboo charcoal (BC)/BiOCl composites were successfully prepared by a simple hydrothermal method, where the BC was derived from the residues of bamboo processing. The BC/BiOCl composites displayed nanosheet structures with tight combination between bamboo charcoal and BiOCl. The oxygen vacancies (OVs) concentration and photoelectric properties of BC/BiOCl composites were boosted with the doped bamboo charcoal. The photocatalytic performance of the composites was evaluated by the degradation of RhB and TCH. Meanwhile, the possible intermediates, degradation pathways and toxicity of the pollutants in the photocatalytic process were elucidated. When the additive dosage of BC and hydrothermal temperature were 5% and 140°C, the 5BC-140 has highest photocatalytic efficiency under visible light irradiation, and the degradation rates of RhB and TCH over the 5BC-140 composite were 97.9% and 69% at 36 min and 120 min, with the kinetic constants of 6.2 times and 2.0 times as high as those of pure BiOCl, respectively. The establishment of Bi-O-C bonds in the BC/BiOCl played a pivotal role in constructing atomic-level interfacial channels to boost the charge carriers’ separation. The enhanced photocatalytic activity was originated from the robust interaction between bamboo charcoal and BiOCl, promoting the rapid transfer of electrons and suppressing the combination of photogenerated electron-hole pairs through the increased oxygen vacancies. In addition, incubation experiments on green beans demonstrated the nontoxicity of contaminant solution degraded by the BC/BiOCl composites.

Gum karaya polymer-based biodegradable silver nanocomposite hydrogel through green approach for photocatalytic dye degradation and antimicrobial activity

The rise in industrialization and population growth has elevated water pollution to a critical environmental concern. This study introduces a novel polymer-mediated silver nanocomposite hydrogel for antibacterial activity and photocatalytic dye degradation for environmental remediation. In this study, silver nanocomposite hydrogels were developed using Karaya gum (KG), acrylamide, N-isopropyl acrylamide (NI), and 2-Bismethacryloyloxy ethyl phosphate (BMEP) as a crosslinker through a radical polymerization process. These hydrogels were utilized as templates for the eco-friendly synthesis of silver nanoparticles by employing an aqueous Canthium leaf extract as a reducing and stabilizing agent. Various analytical methods, including FTIR, UV–Vis, XPS, FESEM, EDX, XRD, AFM, and HRTEM, are characterized by the green synthesized KG-NIB-Ag nanocomposite hydrogel. Evaluation of the KG-NIB-Ag hydrogel involved examining its chemical composition, morphology, size, crystallinity, surface properties, bandgap, and chemical purity. TEM analysis validated an average crystallite size 33.2 nm. Moreover, the photocatalytic performance of the green-synthesized KG-NIB-Ag nanocomposite hydrogel was utilized to examine the degradation of Congo red dye under visible light irradiation. The findings of this study demonstrate that the degradation efficiency of CR reached approximately 73.25 % within 90 min, with a corresponding kinetic rate constant of 0.032 min−1. Furthermore, the antibacterial efficacy of the Ag nanocomposite hydrogel was evaluated against both Staphylococcus aureus and Escherichia coli. The disc diffusion method was employed to assess its antibacterial activity, and the diameter of the inhibition zones was measured. This study introduces an innovative and influential strategy for environmental remediation, emphasizing the potential of KG-NIB-Ag nanocomposite hydrogel in tackling ecological challenges associated with wastewater treatment across various industries.

In-situ assembling novel N-Ti3C2/BiOClxBr1−x composites with enhanced photocatalytic degradation and nitrogen reduction activity

Herein, a collection of novel N-Ti3C2/BiOClxBr1−x composites are fabricated via a simple in-situ sonochemical process. Not only the preparation method for N-Ti3C2 but also the photocatalytic system of N-Ti3C2/BiOClxBr1−x are firstly developed. Multiple characterizations jointly demonstrate the successful fabrication of the composites. Compared to that of BiOClxBr1−x, the maximum improvements of 1.16, 1.25 and 1.26 folds are severally confirmed for the photocatalytic degradation of levofloxacin, Rhodamine B, and methylene blue over N-Ti3C2/BiOClxBr1−x composites. In addition, through radicals trapping tests, the primary active species in photocatalytic degradation process are verified to be O2−. Moreover, N-Ti3C2/BiOClxBr1−x composites also exhibit 1.18 and 1.14 times enhancements for NH3 production compared with that of BiOClxBr1−x with or without the presence of methanol, respectively. In addition, the maximum improvements of photo-current and photo-potential for BiOClxBr1−x are 1.29 and 1.86 folds with the introduction of N-Ti3C2, respectively. The enhanced photocatalytic activity of N-Ti3C2/BiOClxBr1−x composites is owing to the heightened light absorption, increased specific surface area, and accelerated separation of photoinduced carriers. Additionally, the stable photocatalytic properties of N-Ti3C2/BiOClxBr1−x are confirmed by three photocatalytic recycle tests on pollutant degradation and nitrogen reduction combined with X-ray diffraction patterns before and after three recycles. This study suggests that N-Ti3C2 is an efficient ornamentation for boosting photocatalytic activity ofBiOClxBr1−x, which can also be expanded as a promising modifier for other semiconductors.

An S‐scheme AgIn5S8/Bi2MoO6 heterojunction for the photocatalytic degradation of hydrochloride tetracycline

Over the past few decades, the overuse of antibiotics has raised concerns about drinking water and potential health risks, especially the hydrochloride tetracycline (TC‐HCl). Therefore, it is crucial to develop a simple, low‐cost and high‐efficiency photocatalyst for the degradation of the pollutant. A novel photocatalyst with an S‐scheme heterojunction structure of AgIn5S8 and Bi2MoO6 was synthesized by using a solvothermal method. The heterojunction photocatalyst obtained demonstrates superior photocatalytic degradation activity for hydrochloride tetracycline (TC‐HCl) under visible light irradiation. It exhibits higher photocatalytic degradation performance than pure AgIn5S8 and Bi2MoO6 under the same conditions. The heterojunction with 3% AgIn5S8 exhibited the highest degradation efficiency of 63.78% within 40 minutes. Furthermore, the degradation rate is 6.21 times higher than that of AgIn5S8 and 2.18 times higher than that of Bi2MoO6. The improved photocatalytic activity is primarily attributed to the enhanced light absorption and the high rate of carrier separation resulting from S‐scheme heterojunctions.

Effect of shell-dependent variation on the photocatalytic activity of flower-like core-shell SnSe@SnO2

Flower-like core-shell SnSe@SnO2 was prepared by low-temperature in situ oxidation. The relationship between different oxidation times and the formation of core-shell structures of the samples was explored. The results showed that SnSe was obtained by thermal oxidation of SnO2 in close contact with air. The size range of the flower-like core-shell structure SnSe@SnO2 was 15–20 μm. The flower-like structure was self-assembled from nanoplates with a thickness of about 200 nm. This flower-like core-shell structured SnSe@SnO2 has a band gap of about ∼1.4 eV. The electrochemical characterization of the samples was analyzed for charge transfer phenomena at the junctions as well as at the interface between the shell layer and the aqueous solution. The effect of different SnO2 shell layers on the photocatalytic degradation activity of the composites for methylene blue was evaluated. The samples with SnSe oxidized in air for 8 h showed optimal photocatalytic performance and displayed excellent photostability and reusability. In addition, O2− was the main active species for the degradation of the organic dye methylene blue.

2D/2D heterojunction of MgAlTi-LDH/g-C3N4 with oxygen vacancy engineering for enhanced photocatalytic activities under natural sunlight

Semiconductor photocatalysis is an ideal method for wastewater treatment. However, the rapid recombination of photogenerated electron-hole pairs limits the improvement of photocatalytic efficiency. Constructing heterostructures by different energy band-matched semiconductors and surface defect engineering are considered as effective strategies to inhibit the recombination of photogenerated electron-hole pairs. Herein, a novel MgAlTi-LDH/g-C3N4 heterojunction was fabricated by in-situ growth of oxygen vacancy rich MgAlTi-LDH on ultrathin g-C3N4 nanosheets first time for the degradation of methylene blue (MB) under natural sunlight. The optical absorption properties, crystalline phase, microstructure, and morphological analysis of the fabricated materials are subsequently characterized by XRD, FT-IR, UV–vis DRS, TEM, BET and XPS. Owing to Ti-doping, oxygen vacancy rich MgAlTi-LDH exhibited superior photocatalytic activity for MB degradation, which was 5.5 times of that of MgAl-LDH. Furthermore, MgAlTi-LDH/g-C3N4 heterostructures showed a higher photocatalytic activity under visible light irradiation, which was 5.9, 4.9, and 3.2 times of that of MgAl-LDH, MgAlTi-LDH and g-C3N4, respectively. Upon natural sunlight irradiation, MgAlTi-LDH/g-C3N4 can degrade 95 % of MB after 130 min of irradiation. The improvement of photocatalytic activity of MgAlTi-LDH/g-C3N4 was attributed to the synergistic effect of MgAlTi-LDH and g-C3N4, surface oxygen vacancies, and heterostructure interface. This work promotes a new strategy to synthesize high-efficiency photocatalysts for the removal of organic pollutants from wastewater by constructing heterojunctions with surface defects.

Environmental-related applications of ZnO nanopowders: Photocatalytic activity and photoluminescence response to ethanol

Zinc oxide (ZnO) and copper-doped zinc oxide (ZnO:Cu) nanopowders were synthesized via solvothermal methods using methanol and hexamethylenetetramine (HMTA). Undoped ZnO nanopowders underwent calcination in O2-rich and H2-rich atmospheres at 600 °C. Samples were studied by scanning electron microscopy, Brunauer–Emmett–Teller (BET) surface area analysis, X-ray diffraction (XRD), and Raman, photoluminescence (PL) and UV–vis absorbance spectroscopies. The doping and calcinations led to a reduction of the optical bandgap of the nanopowders, while their structure remained hexagonal wurtzite with some changes in lattice parameters and average nanoparticle sizes. The Cu2+ doping led to a BET surface area and violet PL component increase. Samples were also examined for environmental related applications, namely as photocatalyzers for dye degradation and as ethanol optical sensors. For photocatalytic activity in methylene blue degradation under UV, H2-rich calcined powders excelled, with a rate constant of −0.076 min−1, surpassing −0.057 min−1 (ZnO:Cu), −0.056 min−1 (O2-rich calcination), and −0.041 min−1 (as-grown ZnO). We propose that this improvement can be attributed to the formation of ZnO/Zn interfaces stemming from the reduction of surface interstitial zinc by H2 during calcination, in addition to the observed reduction of the ZnO bandgap. The doped nanopowders PL also showed excellent response when exposed to ethanol vapor.

A novel annulated dinuclear dizinc phthalocyanine cross-linked h-BN polyamides for efficient photocatalytic levofloxacin removal from real pharmaceutical wastewater

The alignment of the strong visible-light harvesting phthalocyanine and its metal derivatives onto wide-gap semiconductors has been recognized as a bright approach to fabricate highly effective photocatalysts for energy conversation and environmental restoration. However, the practical application of phthalocyanine-sensitized photocatalysts depends on their incorporation mode between phthalocyanine and basic materials. In this work, a novel high-effective dinuclear zinc (II) phthalocyanine-sensitized photocatalyst is fabricated via covalent immobilization of (Bis(82,112,152-tri-(6-oxyl-2-carboxyl)-naphthaoxytribenzo)[g,l,q]-5,10,15,20-tetraazaporphrinno[b,e]benzene) dizinc (II), (ZnTcPc)2 onto the amino functionalized hexagonal boron nitride (–NH2-h-BN) nanosheets for the first time by a facile condensation strategy. The optimized 9%(ZnTcPc)2/h-BN polymer displays remarkably improved photocatalytic activity in levofloxacin degradation from different aqueous solutions with long-term stability under visible-light illumination. Its decomposition rates reach 81.4%, 71.7% and 90.8% in deionized water, tap water and real pharmaceutical wastewater, respectively. It is approximately 7 times than that of bare h-BN nanosheets in deionized water. The detailed experimental data indicate that the critical role of for improving visible-light harvesting and photoinduced electron transfer capability of h-BN acted by the strongly chemical bond constructed between (ZnTcPc)2 and –NH2-h-BN. The improved photocatalytic mechanism for levofloxacin removal over 9%(ZnTcPc)2/h-BN polymer is proposed according to the results of ESR, UV–vis and fluorescence measurements. Therefore, this unique combination approach affords a carefully designed molecular photocatalyst with great potential application in environmental remediation.

TiO2 nanorod decorated with MoS2 nanospheres: An efficient dual-functional photocatalyst for antibiotic degradation and hydrogen production

The design and preparation of dual-functional photocatalysts for simultaneously realizing photocatalytic wastewater purification and hydrogen energy generation pose significant challenges. This article presents the engineering of a binary heterostructured photocatalyst by combining TiO2 (nanorods) and MoS2 nanosphere using a straightforward solvothermal method and the assessment of the phase structures, morphologies, and optical properties of the resulting nanocomposites using diverse analytical techniques. The TiO2(Rod)/MoS2 composite exhibits remarkable efficacy in degrading ciprofloxacin, achieving 93% removal rate within 1 h, which is four times higher than that of bare TiO2. Moreover, the optimized TiO2(Rod)/MoS2 presents an outstanding hydrogen production rate of 7415 μmol g−1, which is ∼24 times higher than that of pristine TiO2. Under UV–visible light irradiation, the TiO2(Rod)/MoS2 heterojunction displays an exceptional photocatalytic performance in terms of both photodegradation and hydrogen production, surpassing the performance of TiO2 particle/MoS2. The study findings demonstrate that TiO2(Rod)/MoS2 nanocomposites exhibit considerably improved photocatalytic degradation and hydrogen generation activities. Based on the experimental results, a possible mechanism is proposed for the transfer and separation of charge carriers in Z-scheme heterojunctions.

Enhanced Visible Light Photocatalytic Activity of Exfoliated Boron‐TiO2 Composite for Degradation of Rhodamine B and Nitrogen Fixation

AbstractThe design of an efficient, recyclable, visible light photocatalytic system was examined as a viable new green way to address environmental challenges such as removal of pollutants from wastewater and N2 fixation. The exfoliated boron (Bexf)‐Titanium oxide (TiO2) composite visible light active photocatalysts were successfully constructed via a simple wet chemical method by utilizing acetone as a solvent. The composite was evaluated for the photodegradation of Rhodamine B (RhB) dye and reduction of N2, which exhibits improved photocatalytic activity for degradation of RhB as well as for reduction of N2. Experiments with different quenchers indicate that the photogenerated superoxide radical anion (O2⋅−) plays a significant role in the degradation of RhB as well as for N2 reduction reactions. The composite catalyst shows good photostability and there is no significant reduction of the catalyst activity for dye degradation up to 4 cycles of reaction. This work affords a significant view into the design of reusable TiO2 composite materials for photocatalytic RhB degradation and nitrogen fixation.

Sol-Gel technique, characterization and photocatalytic degradation activity of Manganese doped ZnO nanoparticles

Photocatalysis using semiconductor metal oxide stands out as a highly effective and efficient method for eliminating organic pollutants from wastewater. This study aims to assess the photocatalytic capabilities of Mn doped ZnO nanocomposites in degrading methylene blue (MB) dye under ultra-violet light exposure. This study details the synthesis of ZnO photocatalysts through a straightforward one-step sol-gel method, incorporating varying levels of Mn-doping (0%, 2% & 4%). The structural and optical attributes were examined using techniques such as powder X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS) and UV-Vis diffuse reflectance spectra. X-ray diffraction analyses verified the presence of a hexagonal wurtzite crystal structure in all synthesized samples, exhibiting a high degree of crystallinity. In addition, an investigation into the impact of Mn impurities on the photocatalytic performance of ZnO catalysts was conducted in the context of methylene blue (MB) degradation. The experimental findings revealed that the Mn doped ZnO nanoparticles produced exhibited significantly superior photocatalytic performance compared to pure ZnO when used in breaking down methylene blue under UV-light exposure. This study proposes that these Mn doped ZnO could serve as a highly effective photocatalyst for treating water contaminated with certain chemically persistent synthetic organic dyes. The improved photocatalytic capabilities of ZnO nanostructures doped with Mn were ascribed to the synergistic impact of increased surface area in ZnO nanosphere and enhanced efficiency in charge separation resulting from optimized Mn doping. A potential explanation for the heightened photocatalytic performance of Mn-doped ZnO nanostructures is proposed tentatively.

Green synthesis of silver nanoparticles using Solanum sisymbriifolium leaf extract: Characterization and evaluation of antioxidant, antibacterial and photocatalytic degradation activities

The present study conveyed an in-situ synthesis of silver nanoparticles (Ss-AgNPs) using Solanum sisymbriifolium aqueous leaf extract (SsLE) and their biological activities for the first time. The qualitative and quantitative analysis of SsLE imparted significant amounts of reducing entities/ secondary metabolites. A surface plasmon resonance peak at ~430nm of UV–visible spectrum evidenced the formation of Ss-AgNPs. The average particle size of the Ss-AgNPs was found to be 29.87nm through particle size analyzer. Further, FE-SEM, HR-TEM and XRD analysis verified the spherical shape and high degree of crystallinity with face-centred cubic structure of Ss-AgNPs. The EDX, elemental mapping and FTIR spectral studies, confirmed that various phytochemicals/ metabolites of S. sisymbriifolium leaf extract participated in bio-reduction and capping of Ss-AgNPs, which might be accountable for the antioxidant activities. Moreover, SsLE and Ss-AgNPs were found to be a rich source of antioxidants and exhibited effective DPPH, H2O2, ṄO scavenging activity along with Ferric ion reducing antioxidant power. The synthesized Ss-AgNPs showed significant antibacterial activity against gram-positive and gram-negative bacteria. In addition to this, Ss-AgNPs supported the degradation of methylene blue (a cationic dye), by performing as a strong photocatalyst under UV and solar irradiations.

Hydrazine-Assisted Synthesis, Structures, Photoelectricity, and Photocatalysis of Ternary Mercury-Tellurostannate Hybrids with Transition-Metal Complexes.

Tellurostannates are traditionally prepared by multistep reactions using the tellurides SnTe, SnTe2, K4SnTe4, or A6SnTe6 (A = K, Rb, or Cs) as precursors, which are usually prepared by the molten reaction of alkali metals Sn and Te under harsh synthetic conditions. Differently, ternary Hg-tellurostannate hybrids [Mn(en)3]HgSnTe3(Te2) (1) (en = ethylenediamine), [Mn(dien)2]HgSnTe3(Te2) (2), and [Fe(dien)2]HgSnTe3(Te2) (3) (dien = diethylenetriamine) were synthesized by one-pot reactions using Sn and Te powders as starting materials in the presence of hydrazine under mild solvothermal conditions. In 1, HgTe3 and SnTe4 units are joined via Te-sharing to form a 1-D polymeric chain [HgSnTe3(Te2)]n2n-, while the [HgSnTe3(Te2)]n2n- chains in 2 and 3 are composed of HgTe4 and SnTe4 units. The common feature of the [HgSnTe3(Te2)2-]n chains in 1-3 is that they are constructed by both the telluride anion Te2- and the polytelluride anion Te22-. 1-3 exhibited strong photocurrent responses with current densities of 5.26, 3.38, and 3.94 μA cm-2, respectively. They showed effective photocatalytic activities for methylene blue degradation with degradation ratios in the range of 85.3-94.6% after light irradiation for 80 min. Investigation of the photocatalytic mechanism showed that •O2- radicals and h+ holes were the main active substances in the photodegradation.

Removal of antibiotic sulfamethoxazole in water using rapid growing ZnO nanorod

The primary objective of this research is to synthesize ZnO vertical nanorods on a conductive substrate through a novel approach. In this method, ZnO nanorods are grown on kanthal wires using the direct heating (DH) technique. The study investigated the application of ZnO nanorods in photodegradation, specifically in removing Sulfamethoxazole (SMX). Through comprehensive analysis techniques, including XRD, FESEM, and TEM, the successful growth of ZnO nanorods on kanthal wires is confirmed. Their photocatalytic activity in SMX degradation is evaluated at varying concentrations (3 ppm, 5 ppm, 10 ppm) under UV light. Notably, the ZnO sample produced under 80 W power and 120 min emerges as the most promising, exhibiting a high surface area of 36 m2g-1, larger length of 755 nm, and lower diameter of 12 nm, as well as superior SMX photodegradation percentages of 87.64 % (3 ppm), 77.86 % (5 ppm), and 51.84 % (10 ppm) after 60 min. These findings highlight the potential of synthesizing ZnO nanorods via DH technique as an efficient and sustainable solution for removing pharmaceutical contamination in water sources.