Synthesis characterization and application of butyl acrylate mediated eco-friendly silver nanoparticles using ultrasonic radiation.

In the present investigation, with an effort to provide appropriate material for future applications, we have touched on two viable advancement targets: the production of silver nanoparticles (Ag-NPs) employing an ultrasonic approach and the use of Ag-NPs in environmental remediation. A green economical method was involved to prepare Ag-NPs using butyl acrylate as a stabilizer. The following techniques were used for analysing Ag-NPs: energy dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM), powder X-ray diffraction (XRD), and Fourier transformed infrared (FT-IR) spectroscopy. X-ray diffraction (XRD) analysis for the lattice characteristics showed that Ag-NPs have a face-centered structure with an average crystallite size of 9.51-11.83 nm. FE-SEM and TEM analysis were used for morphological investigations, and revealed that Ag-NPs had a spherical shape with an average particle size of 16.27 nm. The EDX profile displayed a strong signal at ∼3.0 keV, which indicated that the samples comprised silver. UV-Visible spectrophotometer with the absorption maximum occurring between 401 and 411 nm further confirmed the formation of Ag-NPs. The dye degradation effect of synthesized Ag-NPs on methylene blue and Rhodamine B was analyzed to assess their ability for environmental remediation, and results showed that around 100% of the dye degradation effect. This study has provided a most plausible mechanism for the dye degradation.

NiAlFe LTH /MoS2 p-n Junction heterostructure composite as an effective visible-light-driven photocatalyst for enhanced degradation of organic dye under high alkaline conditions.

Designing of an effectual heterostructure photocatalyst for catalytic organic pollutant exclusion has been the subject of rigorous research intended to resolve the related environmental aggravation. Fabricating p-n junctions is an effective strategy to promote electron-hole separation of semiconductor photocatalysts as well as enhance the organic toxin degradation performance. In this study, a series of n-type NiAlFe-layered triple hydroxide (LTH) loaded with various ratios of p-type MoS2 was synthesized for forming a heterostructure LTH/MoS2 (LMs) by an in situ hydrothermal strategy. The photocatalysts were characterized by XRD, SEM&EDX, TEM, FT-IR, XPS, as well as UV-vis DRS. The photoactivity of photocatalysts was tested by the degradation of Indigo Carmine (IC) dye. The optimized catalyst (LM1) degrades 100% of indigo dye in high alkaline pH under UV light for 100 min. Besides, the degradation rate of LM1 is 15 times higher than that of pristine NiAlFe-LTH. The enhanced photoactivity is attributed to the synergistic effect between NiAlFe-LTH and MoS2 as well as the p-n junction formation.

Photocatalytic Activity of Ag Nanoparticles Deposited on Thermoexfoliated g-C3N4.

The limited access to fresh water and the increased presence of emergent pollutants (EPs) in wastewater has increased the interest in developing strategies for wastewater remediation, including photocatalysis. Graphitic carbon nitride (g-C3N4) is a 2D non-metal material with outstanding properties, such as a 2.7 eV bandgap and physicochemical stability, making it a promising photocatalyst. This work reports the process of obtaining high-surface-area (SA) g-C3N4 using the thermal-exfoliation process and the posterior effect of Ag-nanoparticle loading over the exfoliated g-C3N4 surface. The photocatalytic activity of samples was evaluated through methylene blue (MB) degradation under visible-light radiation and correlated to its physical properties obtained by XRD, TEM, BET, and UV-Vis analyses. Moreover, 74% MB degradation was achieved by exfoliated g-C3N4 compared to its bulk counterpart (55%) in 180 min. Moreover, better photocatalytic performances (94% MB remotion) were registered at low Ag loading, with 5 wt.% as the optimal value. Such an improvement is attributed to the synergetic effect produced by a higher SA and the role of Ag nanoparticles in preventing charge-recombination processes. Based on the results, this work provides a simple and efficient methodology to obtain Ag/g-C3N4 photocatalysts with enhanced photocatalytic performance that is adequate for water remediation under sunlight conditions.

Facile fabrication of amorphous Al/Fe based metal-organic framework as effective heterogeneous fenton catalyst for environmental remediation.

This study presents a facile preparation and durable amorphous Fe and Al-based MOF nanoplate (AlFe-BTC MOFs) catalyst with notable stability in Fenton reactions. Rigorous characterization using XRD, HR-TEM, and BET confirms the amorphous nature of the synthesized AlFe-BTC MOFs, revealing mesopores (3.4 nm diameter), a substantial surface area (232 m2/g), and a pore volume of 0.69 cc/g. XPS analysis delineates distinct Al2p and Fe2p binding energy values, signifying specific chemical bonding. FE-SEM elemental mapping elucidates the distinctive distribution of Fe and Al within the framework of AlFe-BTC MOFs. In catalytic activity testing, the amorphous AlFe-BTC MOFs exhibited outstanding performance, achieving complete degradation of Methylene blue (MB) dye and 78% TOC removal over 45 min of treatment under mild reaction conditions. The catalyst's durability was assessed, revealing about 75% TOC removal and complete dye decomposition over five successive recycles, with less than 1 mg/L of Fe and Al leaching. UV-Vis spectra revealed the destruction of MB dye over multiple recycling studies. Based on this finding, the amorphous AlFe-BTC MOF nanoplates emerge as a promising solution for efficient dye removal from industrial wastewater, underscoring their potential in advanced environmental remediation processes.

Structure-led manifestation of photocatalytic activity in magnetically recoverable spinel CuFe2O4nanoparticles and its application in degradation of industrial effluent dyes under solar light.

An efficient removal of the photocatalysts used in the decontamination of water is crucial after its application beside its expected visible light sensitive activities. This study presents the synthesis of magnetically separable CuFe2O4nanoparticles (CFNPs) with enhanced photoactivity under AM 1.5G sunlight. A simple two-step process involving co-precipitation and hydrothermal treatment is employed, with subsequent annealing at temperatures from 200 °C to 1000 °C to synthesize the CFNPs. The characteristic features of the highest photoactive tetragonal phase of CFNP are confirmed by powder XRD studies with Rietveld refinement. This scheme strategically controls the growth of a highly photoactive tetragonal phase with predominant (224) facets over other less active facets in cubic CuFe2O4. Mott-Schottky analysis confirms the p-type semiconducting nature of CFNPs. A favourable direct optical band gap of 1.73 eV as well as photoluminescence emission quenching for visible photons show that the (224) oriented CFNPs are good photocatalysts in the visible spectrum with demonstrated organic dye degradations, including methylene blue and others. A density functional theory-based approach validates that the adsorption of such dye is thermodynamically more favourable on (224) facets of CuFe2O4to facilitate the redox action by the excitons.

Fabrication of MoS2 restrained magnetic chitosan polysaccharide composite for the photocatalytic degradation of organic dyes.

Chitosan (CS) polysaccharide is expected to exhibit greater ionic conductivity, which can be attributed to its increased amino group content when it is blended with different semiconducting materials. Herein, the work used this conducting ability of chitosan and prepared a heterogeneous MoS2-induced magnetic chitosan (MF@CS) composite via the co-precipitation method, which was used to scrutinize the catalytic performance with Methylene Blue (MB) and Malachite Green (MG) dyes by visible light irradiation. The saturation magnetization value of the MF@CS composite is found to be 7.8 emu/g, which is less when compared to that of pristine Fe3O4 (55.7 emu/g) particles. The bandgap of the MF@CS composite is âˆ¼ 2.17eV, which exceeds the bandgap (Eg) of bare MoS2 of 1.80 eV. The maximum color removal of 96.3 % and 93.4 % for MB and MG dyestuffs is recognized in the exposure of the visible spectrum, respectively. At a starting dye dosage of 30 mg/L, 0.1 g/L of MF@CS, a pH level of 8-11, and 70 min of contact with direct light. The photocatalyst provides extremely good durability for a maximum of five phases. Hence, the MF@CS matrix is a viable and appropriate substance for the efficient treatment of effluents containing dye molecules.

Exploring the potential of a Ephedra alata leaf extract: Phytochemical analysis, antioxidant activity, antibacterial properties, and green synthesis of ZnO nanoparticles for photocatalytic degradation of methylene blue.

Ephedra alata leaf extracts have therapeutic properties and contain various natural compounds known as phytochemicals. This study assessed the phytochemical content and antioxidant effects of a Ephedra alata leaf extract, as well as zinc oxide (ZnO) nanoparticle production. The extract contained phenolic acids, including vanillic acid, chlorogenic acid, gallic acid, p-coumaric acid, vanillin and rutin. Its total phenolic content and total flavonoid content were 48.7 ± 0.9 mg.g-1 and 1.7 ± 0.4 mg.g-1, respectively. The extract displayed a DPPH inhibition rate of 70.5%, total antioxidant activity of 49.5 ± 3.4 mg.g-1, and significant antimicrobial activity toward Gram-positive and negative bacteria. The synthesized ZnO nanoparticles had spherical shape, crystallite size of 25 nm, particle size between 5 and 30 nm, and bandgap energy of 3.3 eV. In specific conditions (90 min contact time, pH 7, and 25°C), these nanoparticles efficiently photodegraded 87% of methylene blue, suggesting potential applications for sustainable water treatment and pollution control.

Anodizing Tungsten Foil with Ionic Liquids for Enhanced Photoelectrochemical Applications.

This research examines the influence of adding a commercial ionic liquid to the electrolyte during the electrochemical anodization of tungsten for the fabrication of WO3 nanostructures for photoelectrochemical applications. An aqueous electrolyte composed of 1.5 M methanesulfonic acid and 5% v/v [BMIM][BF4] or [EMIM][BF4] was used. A nanostructure synthesized in an ionic-liquid-free electrolyte was taken as a reference. Morphological and structural studies of the nanostructures were performed via field emission scanning electron microscopy and X-ray diffraction analyses. Electrochemical characterization was carried out using electrochemical impedance spectroscopy and a Mott-Schottky analysis. From the results, it is highlighted that, by adding either of the two ionic liquids to the electrolyte, well-defined WO3 nanoplates with improved morphological, structural, and electrochemical properties are obtained compared to samples synthesized without ionic liquid. In order to evaluate their photoelectrocatalytic performance, the samples were used as photocatalysts to generate hydrogen by splitting water molecules and in the photoelectrochemical degradation of methyl red dye. In both applications, the nanostructures synthesized with the addition of either of the ionic liquids showed a better performance. These findings confirm the suitability of ionic liquids, such as [BMIM][BF4] and [EMIM][BF4], for the synthesis of highly efficient photoelectrocatalysts via electrochemical anodization.

Optimizing cyanine dye properties for enhanced dyeing and inkjet printing on diverse Substrates: Photophysical and colorimetric investigations.

Cyanine-based cationic dyes with different substituents in the donor unit were easily synthesized using readily available starting materials. The prepared dye molecules were spectroscopically characterized by NMR, FT-IR, and HR-Mass, and their thermal stability was measured by TGA, DSC, and XRD. Based on the TGA and DSC measurements, it was concluded that all the dyes are thermally stable up to 200 °C. Also, powder XRD was studied for all dyes to identify the explicit crystallinity and morphological nature of the dyes. A dye dispersion solution was prepared for the proper dyeing of modacrylic fabric and the dyed fabric showed good color strength K/S for dyes R1, R2, and R6 and fragile color strength for R3, R4,and R5. These dyes are also used for printing on substrates like paper and fabric using ink-jet printing. These dyes were also used for transferability printing applications on various fabrics.

Versatility of copper-iron bimetallic nanoparticles fabricated using Hibiscus rosa-sinensis flower phytochemicals: various enzymes inhibition, antibiofilm effect, chromium reduction and dyes removal.

Bimetallic nanoparticles (NPs) are considered superior in terms of stability and function with respect to its monometallic counterparts. Hence, in the present study Hibiscus rosa-sinensis flower extract was used to synthesis copper-iron bimetallic nanoparticles (HF-FCNPs). HF-FCNPs was characterized and its applications (biological and environmental) were determined. HF-FCNPs were spherical in shape with high percentage of copper inducted into the NPs. HF-FCNPs inhibited mammalian glucosidases [maltase (IC50: 548.71 ± 61.01 µg/mL), sucrase (IC50: 441.34 ± 36.03 µg/mL), isomaltase (IC50: 466.37 ± 27.09 µg/mL) and glucoamylase (IC50: 403.12 ± 14.03 µg/mL)], alpha-amylase (IC50: 16.27 ± 1.73 µg/mL) and acetylcholinesterase [AChE (IC50: 0.032 ± 0.004 µg/mL)] activities. HF-FCNPs showed competitive inhibition against AChE, maltase and sucrase activities; mixed inhibition against isomaltase and glucoamylase activities; whereas non-competitive inhibition against α-amylase activity. HF-FCNPs showed zone of inhibition of 16 ± 2 mm against S. mutans at 100 µg/mL concentration. HF-FCNPs inhibited biofilm formation of dental pathogen, S. mutans. SEM and confocal microscopy analysis revealed the disruption of network formation and bacterial cell death induced by HF-FCNPs treatment on tooth model of S. mutans biofilm. HF-FCNPs efficiently removed hexavalent chromium in pH-independent manner and followed first order kinetics. Through Langmuir isotherm fit the qmax (maximum adsorption capacity) was determined to be 62.5 mg/g. Further, HF-FCNPs removed both anionic and cationic dyes. Altogether, facile synthesis of HF-FCNPs was accomplished and its biological (enzyme inhibition and antibiofilm activity) and environmental (catalyst to remove pollutants) applications have been understood.

Highly efficient visible-light driven dye degradation via 0D BiVO4 nanoparticles/2D BiOCl nanosheets p-n heterojunctions.

The construction of hybrid heterojunction photocatalysts is an effective strategy to improve the utilization of photogenerated carriers and photocatalytic activity. To enhance the separation distance of photogenerated carriers and accelerate the effective separation at the heterojunction of the interface, a unique 0D-2D hierarchical nanostructured p-n heterojunction was successfully fabricated in this work. BiOCl (BOC) nanosheets (p-type) were in situ grown on BiVO4 (BVO) nanoparticles (n-type) using the microemulsion-calcination method for highly efficient visible-light-driven organic dye degradation. Compared with pure BVO (the degradation rate of rhodamine B (RhB): about 32.0% in 55 min, the mineralization rate: 24.9% in 120 min), the RhB degradation rate can reach about 99.5% in 55 min and the mineralization rate of 62.1% in 120 min by utilizing BVO/25%BOC heterojunction photocatalyst under visible light irradiation. Various characterizations demonstrate that the formation of BVO/BOC p-n heterojunction greatly facilitates photogenerated carriers separation efficiency. Meanwhile, the results of the scavenging experiments and electron spin resonance tests indicate that ·O2- and h+ are the prominent active species for Rh B degradation. In addition, possible degradation pathways for Rh B were proposed using LC-MS tests. This work proves that building low dimensional p-n heterojunction photocatalysts is a promising strategy for developing photocatalysts with high efficiency.

Highly reusable Bi2O3/electron-Cu-shuttle in-situ immobilized polyacrylonitrile fibrous mat for efficient photocatalytic degradation of methylene blue and rhodamine B dyes.

Organic semiconductor-based photocatalysts have been alluring due to their edge over inorganic photocatalysts. In this study, a reusable copper-bismuth oxide/polyacrylonitrile (Cu-Bi2O3/PAN) fibrous mat was prepared by fast-process flame spray pyrolysis and electrospinning for photocatalytic degradation of methylene blue (MB) and rhodamine B (RhB) dyes. The results confirmed a well-defined morphology of Cu-Bi2O3/PAN fibers and good coordination of flame-made Cu-Bi2O3 particles with the functional groups of PAN. The Cu-Bi2O3/PAN fibrous mat exhibits remarkable photocatalytic performance of 96.2% MB and 98.6% RhB degradation, with a reaction rate as high as about 4.5- and 10.2-times than that of flame-made Cu-Bi2O3 particles and PAN under neutral condition, even after 10 cycles. The Cu-Bi2O3/PAN exhibits complete degradation of MB and RhB in 90 and 150 min under alkaline and slightly acidic conditions, respectively. The synergistic effect of Cu-Bi2O3 and coordination bond between particles and functional groups of PAN promoted carrier migration, suppressed recombination of carriers and provided abundant radicals on the surface of the mat. Superoxide and hydroxyl radicals were the major active species involved in the degradation of RhB and MB, respectively. This work provides an insight into designing the Cu-metal-shuttle based photocatalysts to optimize fibrous mat application in water remediation.

A novel nanocomposite for photocatalytic rhodamine B dye removal from wastewater using visible light.

Providing safe access to water and addressing the impact of waterborne diseases, which claim over two million lives annually, is a major contribution to water purification. The study introduces a novel nanocomposite, Ch/Fe3O4/α-MoO3, which exhibits outstanding photocatalytic efficacy under visible light. An in-depth investigation of the nanocomposite's synthesis, characterization, and photodegradation mechanisms reveals its outstanding capabilities. Photocatalytic activity is influenced by the catalytic dose, pH, dye concentration, and reaction time, according to the study. A response surface method is used to determine the optimal conditions for Rhodamine B degradation, which results in 96.3% removal efficiency at pH 8.5, dye concentration 25 mg/L, nanocomposite dose at 22 mg/L, and reaction time 50 min. As a result of its high surface area, biocompatibility, availability, and magnetization with iron compounds, Chitosan is an excellent substrate for enhancing the photocatalytic properties of MoO3 nanoparticles. A nanocomposite with an energy band of 3.18 eV exhibits improved visible light absorption. This study confirms the nanocomposite's recyclability and stability, affirming its practicality. Besides dye removal, it offers hope for the global quest for clean water sources by addressing a broader range of waterborne contaminants. By combining molybdenum and magnetite, nanocomposite materials facilitate the degradation of pollutant and bacteria, contributing positively to society's quest for clean and safe water. It emphasizes the role nanotechnology plays in preserving human health and well-being in combating waterborne diseases.

Potential of biosynthesized titanium dioxide nanoparticles towards wastewater treatment and antimicrobial activity.

This study reports a green, sustainable, reliable, and cost-effective method for the biosynthesis of titanium dioxide nanoparticles (TiO2NPs) using the leaf and stem extracts of Carissa opaca. The newly synthesized biogenic TiO2NPs were confirmed and characterized using various analytical techniques, such as Fourier transform infrared spectroscopy (FTIR), high-resolution transmission electron microscopy (HRTEM), dynamic light scattering (DLS), zeta potential, X-ray diffraction (XRD), inductively coupled plasma analysis (ICP), and scanning electron microscopy (SEM). Both the electron microscopy, i.e., SEM and HRTEM confirmed the spherical/hexagonal crystalline structure of TiO2NPs with an average particle size range from 72.8 to 84.11 nm. These nanoparticles (NPs) exhibited aggregation and possessed a diverse array of functional groups on their surface. Biosynthesized TiO2NPs showed excellent photocatalytic activity against methylene blue (MB) with decolorizing efficiency of 87.8% and 91.95%, whereas in case of methyl violet (MV), the decolorizing efficiency of 82.1% and 71.9% was observed with nanoparticles synthesized using leaf and stem extract, respectively. The newly synthesized NPs have also shown good antibacterial potential against Klebsiella pneumoniae and Staphylococcus aureus. This new biomimetic approach offers an economical and environmentally benign alternative for the removal of hazardous dyes and may find a place for antimicrobial applications.

Layer-by-layer assembled graphitic carbon nitride membranes for water treatment.

Meeting societal demand for potable water supply remains one of the prioritized challenges faced in the modern era. The anthropogenic intervention has led to a dire situation threatening ecological balance and human health. There is an inevitable need for the development of new technologies and innovations in existing technologies for water treatment. Photocatalytic Membrane technology, encompassing the merits of membrane filtration and photocatalytic degradation has evolved as a potential and reliable technology for sustainable water treatment. Innovations in photocatalytic materials and membrane fabrication techniques can lead to the goal of commercialization of membrane water treatment technology. Herein, we demonstrate the potential of graphitic carbon nitride (g-C3N4) and its functionalized analog as photocatalytic membranes for sustainable water treatment. g-C3N4 and Tetracarboxyphenylporphyrin sensitized g-C3N4 (g-C3N4/TCPP) was introduced onto commercial nylon membrane surface via a layer-by-layer (LBL) assembly method using chitosan and sodium salt of polystyrene sulphonic acid as polyelectrolytes. The fabricated membranes were characterized to ensure the integration of the photocatalysts. The performance of the membranes for water treatment was assessed by selecting some common dyes as model pollutants. The modified membranes exhibited excellent flux recovery and could afford high rejection rates upon irradiation indicating the prospects for sustainable filtration.

Bactericidal, anti-biofilm, anti-oxidant potency and catalytic property of silver nanoparticles embedded into functionalised chitosan gel.

Chitosan is a versatile biocompatible polysaccharide which has attracted great attention for gel synthesis. Its reducing character is specifically exploited for nanoparticle synthesis via green approach. A silver nanocomposite synthesized using this gel, with a novel gelling agent 2,4,6-trihydroxy benzaldehyde, was found to be a promising candidate for several applications including anti-bacterial, anti-biofilm and anti-oxidant activity as well as catalysis. The nanocomposite was well characterized using various spectroscopic and microscopic techniques such as IR, TGA, XRD, XPS, SEM and TEM. The nanocomposite exhibited high bactericidal activity against both S. aureus and E. coli. Further, it was evaluated for anti-biofilm forming property and its potency as antioxidant agent. The nanocomposite served as a catalyst for degradation of Methyl Orange and Rhodamine B at high concentrations (in the range of mM) with a catalytic efficiency of 98.58 % and 99.56 % within 3 min and 5 min respectively.

Enhanced photocatalytic activity of V3O7 / V2O5 - reduced graphene oxide nanocomposite towards methylene blue dye degradation.

This work investigates the photocatalytic performance of V2O5 and V3O7 nanoparticles and their nanocomposites with rGO. The as-annealed V2O5 and V3O7 nanoparticles exhibited pure orthorhombic and monoclinic structures with an optical bandgap of 2.3 and 2.5 eV, respectively. The corresponding vibrational modes using Raman and FTIR spectroscopy analysis further confirm the form. The morphological studies reveal that V2O5 and V3O7 nanoparticles possess plate and petal-like morphology, respectively. Moreover, in the case of V2O5/V3O7-rGO nanocomposites, the plate/petal-like nanoparticles are embedded within rGO sheets. Incorporating nanoparticles within rGO sheets has quenched the green photoluminescence emission, enhancing their photocatalytic performance upon irradiation with white light of 100 mW/cm2. This is ascribed to the effective transport of interfacial electrons from vanadium oxide nanoparticles to the rGO surface, reducing the recombination of photogenerated charge carriers. These results indicate that the vanadium oxide/rGO nanocomposites have potential applications in wastewater treatment.

A novel visible-light-driven Z-scheme C3N5/BiVO4 heterostructure with enhanced photocatalytic degradation performance.

As a visible-light response semiconductor materials, bismuth vanadate (BiVO4) is extensively applied in photodegradation organic dye field. In this study, we synthesized C3N5 nanosheets and coupled with decahedral BiVO4 to construct a Z-scheme C3N5/BiVO4 heterostructure with close interface contact. By introducing C3N5 into BiVO4, the built Z-scheme transfer pathway provides silky channel for charge carrier migration between different moieties and enables photoexcited electrons and holes accumulated on the surface of BiVO4 and C3N5. The accelerated separation of charge carriers ensures C3N5/BiVO4 heterostructures with a powerful oxidation capacity compared with pure BiVO4. Due to the synergistic effect in Z-scheme heterostructure, the C3N5/BiVO4 demonstrated an improved photodegradation ability of rhodamine B (RhB) and methylene blue (MB) that of bare BiVO4.

Tungsten-based Lindqvist and Keggin type polyoxometalates as efficient photocatalysts for degradation of toxic chemical dyes.

Photocatalytic dye degradation employing polyoxometalates (POMs) has been a research focus for several years. We report the facile synthesis of tungsten-based Lindqvist and Keggin-type POMs that degrade toxic chemical dyes, methyl orange (MO) and methylene blue (MB), respectively. The Lindqvist POM, sodium hexatungstate, Na2W6O19, degrades MO under 100 W UV light irradiation within 15 min, whereas the Keggin POM, Ag4PW11VO40, degrades MB under 20 W visible light source within 180 min. The effect of various operating parameters, such as photocatalyst concentration, pH, time, and initial dye concentration, were assessed in the degradation of both dyes. The photoelectrochemical performance of the as-synthesized polyoxometalates shows that the Ag4PW11VO40 shows 2.4 times higher photocurrent density than Na2W6O19 at a potential of 0.9 V vs. Ag/AgCl. Electrochemical impedance analysis reveals that Ag4PW11VO40 exhibits much lower charge transfer resistance as compared to Na2W6O19, which indicates facile charge transfer at the electrode-electrolyte interface. Further Mott-Schottky measurements reveal that both the catalysts possess n-type semiconductivity and the charge carrier concentration of Ag4PW11VO40 (5.89 × 1019 cm-3) is 1.4 times higher as compared to Na2W6O19 (4.25 × 1019 cm-3). This work offers a new paradigm for designing polyoxometalates suitable for efficient photocatalytic degradation of organic dyes.

High Tribocatalytic Performance of FeOOH Nanorods for Degrading Organic Dyes and Antibiotics.

Tribocatalysis is vitally important for electrochemistry, energy conservation, and water treatment. Exploring eco-friendly and low-cost tribocatalysts with high performance is crucial for practical applications. Here, the highly efficient tribocatalytic performance of FeOOH nanorods is reported. The factors related to the tribocatalytic activity such as nanorod diameter, surface area, and surface roughness are investigated, and the diameter of the FeOOH nanorods is found to have a significant effect on their tribocatalytic performance. As a result, under ultrasonic excitation, the optimized FeOOH nanorods exhibit superior tribocatalytic degradation toward rhodamine B (RhB), acid orange 7, methylene blue, methyl orange dyes, and their mixture. The RhB and mixed dyes are effectively degraded within 20 min (k = 0.179 min-1 ) and 35 min (k = 0.089 min-1 ), respectively, with the FeOOH nanorods showing excellent reusability. Moreover, antibiotics, such as tetracycline hydrochloride, phenol, and bisphenol A are efficiently degraded. Investigation of the catalytic mechanism reveals that the friction-generated h+ as well as these yielded •OH and •O2 - active radicals participate in the catalytic reaction. This work not only shed light on the design of high-performance tribocatalyst but also demonstrates that by harvesting mechanical energy, the FeOOH nanorods are promising materials for removing organic contaminants in wastewater.