Construction of Ag 3 PO 4 /Ag 2 MoO 4 Z-scheme heterogeneous photocatalyst for the remediation of organic pollutants

Silver molybdate: an excellent optical limiting material under nanoregime for photonic device application

There is a mounting demand for nonlinear optical materials with superior optical limiting performance which has a noticeable impact on protecting the delicate optical components from laser-induced damage. Transition metal molybdates have garnered attention in the nonlinear optics field due to their outstanding optical and luminescent properties, which give rise to widespread applications in next-generation optoelectronics devices. The structural confirmation of the as prepared silver molybdate nanoparticles were made by XRD and Raman spectroscopy analysis. The linear optical properties and the band gap of the synthesized material were studied using UV-Visible and photoluminescence spectroscopy. SEM analysis revealed the pebble like morphology of the silver molybdate nanostructures. The nonlinear responses of the samples were studied using open aperture z-scan approach with Nd:YAG pulsed laser (532 nm, 9 ns, 10 Hz). The sample exhibits reverse saturable absorption pattern attributed to the two photon absorption (2PA) mechanism. The obtained OL threshold value is in the order of 1012 which is suitable for fabricating optical limiters in nano second pulsed laser regime.

Spectroscopy and visible-light driven photocatalytic properties of a microcrystalline Cu-complex derived from a novel Gabapentin Schiff base

A novel Gabapentin derivative Schiff base Gasa was synthesized by condensing Gabapentin with salicylaldehyde, which was further coordinated with Cu2+ in methanol to give a microcrystalline Cu(II) complex Cu(Gasa)2. The synthesized Gasa and Cu(Gasa)2 were further characterized by single-crystal X-ray diffraction, scanning electron microscopy (SEM), as well as the FT-IR, Raman, electronic and fluorescence spectra. Cu(Gasa)2 exhibited excellent visible-light driven photocatalytic activities in removal of Congo red (CR) and Methylene blue (MB) dyes from aqueous solution in the presence of H2O2 as oxidant. It was revealed that ∙OH radicals played the most important role in the photodegradation processes of organic dyes, and the photodegradation of CR and MB fitted well with the pseudo-first-order kinetic model. In addition, solid state luminescent properties of Gasa and Cu(Gasa)2 were also studied in detail.

Synthesis of Ag3PO4/Ag/g-C3N4 Composite for Enhanced Photocatalytic Degradation of Methyl Orange

In this study, we have successfully constructed Ag3PO4/Ag/g-C3N4 heterojunctions via the hydrothermal method, which displays a wide photo-absorption range. The higher photocurrent intensity of Ag3PO4/Ag/g-C3N4 indicates that the separation efficiency of the photogenerated electron-hole pairs is higher than that of both Ag3PO4 and Ag/g-C3N4 pure substances. It is confirmed that the efficient separation of photogenerated electron-hole pairs is attributed to the heterojunction of the material. Under visible light irradiation, Ag3PO4/Ag/g-C3N4-1.6 can remove MO (~90%) at a higher rate than Ag3PO4 or Ag/g-C3N4. Its degradation rate is 0.04126 min-1, which is 4.23 and 6.53 times that of Ag/g-C3N4 and Ag3PO4, respectively. After five cycles of testing, the Ag3PO4/Ag/g-C3N4 photocatalyst still maintained high photocatalytic activity. The excellent photocatalysis of Ag3PO4/Ag/g-C3N4-1.6 under ultraviolet-visible light is due to the efficient separation of photogenerated carriers brought about by the construction of the Ag3PO4/Ag/g-C3N4 heterostructure. Additionally, Ag3PO4/Ag/g-C3N4 specimens can be easily recycled with high stability. The effects of hydroxyl and superoxide radicals on the degradation process of organic compounds were studied using electron paramagnetic resonance spectroscopy and radical quenching experiments. Therefore, the Ag3PO4/Ag/g-C3N4 composite can be used as an efficient and recyclable UV-vis spectrum-driven photocatalyst for the purification of organic pollutants.

Indium selenide/silver phosphate hollow microsphere S-scheme heterojunctions for photocatalytic hydrogen production with simultaneous degradation of tetracycline

Designing heterojunction photocatalysts with strong interfacial interactions is an effective way to reduce the recombination of photogenerated charge carriers. Here, silver phosphate (Ag₃PO₄) nanoparticles are coupled with hollow flower-like indium selenide (In₂Se₃) microspheres by a facile Ostwald ripening and in-situ growth method, resulting in the construction of In₂Se₃/Ag₃PO₄ hollow microsphere step-scheme (S-scheme) heterojunction with a large contact interface. The flower-like In₂Se₃ with hollow and porous structure provides a large specific surface area and numerous active sites for photocatalytic reactions to take place. The photocatalytic activity was tested by measuring the hydrogen evolution from antibiotic wastewater, and the H₂ evolution rate of In₂Se₃/Ag₃PO₄ reached 4206.4 µmol g^-1h^-1 under visible light, which is approximately 2.8 times greater than that of In₂Se₃. In addition, the amount of tetracycline (TC) degradation when it was used as a sacrificial agent is about 54.4% after 1 h. On the one hand, Se-P chemical bonds act as electron transfer channels in the S-scheme heterojunctions, which can facilitate the migration and separation of photogenerated charge carriers. On the other hand, the S-scheme heterojunctions can retain the useful holes and electrons with higher redox capacities, which is very favorable for the generation of more •OH radicals and the photocatalytic activity is greatly enhanced. This work provides an alternative design approach for photocatalysts toward hydrogen evolution in antibiotic wastewater.

Preparation of Ag3PO4/CoWO4 S-scheme heterojunction and study on sonocatalytic degradation of tetracycline

In this study, 0.6Ag3PO4/CoWO4 composites were synthesized by hydrothermal method. The prepared materials were systematically characterized by techniques of scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray diffractometer (XRD), X-ray photoelectron spectroscopy (XPS), N2 adsorption/desorption, and UV-vis diffuse reflectance spectrum (DRS). Furthermore, the sonocatalytic degradation performance of 0.6Ag3PO4/CoWO4 composites towards tetracycline (TC) was investigated under ultrasonic radiation. The results showed that, combined with potassium persulfate (K2S2O8), the 0.6Ag3PO4/CoWO4 composites achieved a high sonocatalytic degradation efficiency of 97.89 % within 10 min, which was much better than bare Ag3PO4 or CoWO4. By measuring the electrochemical properties, it was proposed that the degradation mechanism of 0.6Ag3PO4/CoWO4 is the formation of S-scheme heterojunction, which increases the separation efficiency of electron-hole pairs (e--h+) and generates more electrons and holes, thereby enhancing the degradation activity. The scavenger experiments confirmed that hole (h+) was the primary active substance in degrading TC, and free radicals (OH) and superoxide anion radical (O2-) were auxiliary active substances. The results indicated that 0.6Ag3PO4/CoWO4 nanocomposites could be used as an efficient and reliable sonocatalyst for wastewater treatment.

Silver Trimolybdate (Ag2Mo3O10.2H2O) Nanorods: Synthesis, Characterization, and Photo-Induced Antibacterial Activity under Visible-Light Irradiation

The present study reports the synthesis, characterization, and antibacterial properties of silver trimolybdate (Ag2Mo3O10.2H2O) nanorods. The synthesis was performed using a conventional hydrothermal method. The sample was characterised by scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, UV-Vis-NIR diffuse reflectance, thermogravimetric analysis (TGA), and differential scanning calorimeter (DSC). The direct antibacterial activity was evaluated using the microdilution method to determine the minimum inhibitory concentration (MIC). To assess the ability of Ag2Mo3O10.2H2O nanorods to modulate antibacterial resistance, the MIC of aminoglycosides was established in the presence of a subinhibitory concentration of this substance alone and associated with LED light exposure. The characterization of the sample indicated that the synthesis of silver trimolybdate generated nanometric crystals with rod-like morphology, without secondary phases. The treatment with Ag2Mo3O10.2H2O nanorods alone or combined with visible LED lights exhibited clinically relevant antibacterial activity against both Gram-negative and Gram-positive bacteria. This nanostructure presented a variable antibiotic-modulating action, which was not improved by visible LED light exposure. Nevertheless, LED lights showed promising antibiotic-enhancing activities in the absence of Ag2Mo3O10.2H2O nanorods. In conclusion, silver trimolybdate dihydrate nanorods have antibacterial properties that can be photocatalysed by visible-light exposure. While showing the potential use to combat antibacterial resistance, the simultaneous combination of silver trimolybdate, visible LED lights, and antibacterial drugs should be carefully analysed to avoid antagonist effects that could impair the effectiveness of antibiotic therapy.

Construction of nitrogen vacant g-C3N4 nanosheet supported Ag3PO4 nanoparticle Z-scheme photocatalyst for improved visible-light photocatalytic activity

The superior photocatalytic activity of semiconductor-based photocatalytic materials has attracted great attention. In this work, a series of novel Ag3PO4/g-C3N4-x (APO/CNx) composites with the Z-scheme structure were fabricated through a facile precipitation method. B naphthol, a typical phenolic compound, was selected to evaluate the photocatalytic activity of all as-prepared photocatalysts. The obtained APO/CNx composites exhibited excellent photocatalytic activity for degradation of B naphthol under visible-light irradiation. Experimental results showed that the degradation rate toward B naphthol could reach to 90.5% for 180 min, which was almost 3.66 times higher than pure g-C3N4, indicating that the presence of nitrogen vacancies and Z-scheme structure could efficiently improve the photocatalytic performance of pure g-C3N4. Furthermore, the results of trapping experiments and electron spin resonance (ESR) spectroscopy manifest that •O2- and •OH radicals were the predominant active substances for B naphthol degradation, and the possible mechanism of improved photocatalytic performance was elucidated. This work will provide an innovative perspective for constructing Z-scheme photocatalysts for the application of photocatalytic in the field of wastewater treatment.

Plastic optical fibres applied on the photocatalytic degradation of phenol with Ag2MoO4 and ß-Ag2MoO4/Ag3PO4 under visible light

In this study, plastic optical fibre (POF) was considered as a light-transmitting medium and substrate for use in a photocatalytic environmental purification system, using Ag₂MoO₄ and β-Ag₂MoO₄/Ag₃PO₄ as photocatalysts. Pure Ag₂MoO₄ and a β-Ag₂MoO₄/Ag₃PO₄ composite were synthesized using a facile precipitation method. The composition, structures and optical properties of as-prepared catalysts were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), field-emission scanning electron microscopy (FESEM), UV/Vis diffuse reflectance spectroscopy (UV/Vis DRS), BET surface area and TGA/DTG. The catalysts were immobilized on POF and on the glass reactor surface and their efficiency in the phenol degradation was evaluated in a batch reactor under visible light. The use of POF offers advantages such as ease of handling and good adherence characteristics to support Ag₂MoO_4. The photoactivity follows the order β-Ag₂MoO₄/Ag₃PO₄ ≅ Ag₂MoO₄> TiO₂ P25, for photocatalysts immobilized on the glass reactor surface or in aqueous suspension. The immobilization of Ag₂MoO₄ on POF revealed that thinner Ag₂MoO₄ coatings achieved faster pollutant removal rates from solution, and the optimal catalyst deposition is 0.64 mg/cm², causing maximum the light penetration and electron-hole generation close to the solid-liquid interface.

Fabrication of a novel ternary heterojunction composite Ag2MoO4/Ag2S/MoS2 with significantly enhanced photocatalytic performance

A novel ternary heterojunction Ag₂MoO₄/Ag₂S/MoS₂ was successfully fabricated via a facile two-step method. The prepared ternary heterojunction showed much enhanced catalytic activity compared with monomers and binary heterojunctions.

Microwave- and Formaldehyde-Assisted Synthesis of Ag-Ag3PO4 with Enhanced Photocatalytic Activity for the Degradation of Rhodamine B Dye and Crude Oil Fractions

The release of crude oil and water-soluble dyes into our marine environment is a major global problem. An efficient semiconductor Ag-Ag₃PO₄ photocatalyst was synthesized using formaldehyde as a reducing agent to form surface active Ag on Ag₃PO₄ under microwave radiation for heating, and its potential in destroying environmental pollutants has been examined. The diffuse reflectance spectroscopy of Ag-Ag₃PO₄ revealed an enhanced absorption in the visible light region. The rate of photocatalytic degradation of rhodamine B by Ag-Ag₃PO₄ was over 4-fold compared to Ag₃PO₄. The potential application of Ag-Ag₃PO₄ in oil spill remediation was also examined through photocatalytic degradation of benzene, n-hexane, and 1:1 v/v benzene/methanol crude oil-soluble fractions. UV-vis and gas chromatography-mass spectrometry analysis of the crude oil components after visible light irradiation showed excellent degradation. The photocatalytic efficiency enhancement of Ag-Ag₃PO₄ is attributed to the excellent electron trapping of silver nanoparticles deposited on the surface of Ag₃PO₄. This work will motivate future studies to develop recyclable visible light photocatalysts for many applications.

Fabrication of ternary Ag3PO4/Co3(PO4)2/g-C3N4 heterostructure with following Type II and Z-Scheme dual pathways for enhanced visible-light photocatalytic activity

A novel ternary Ag₃PO₄/Co₃(PO₄)₂/g-C₃N₄ (APO/CPO/CN) heterostructure photocatalyst was successfully synthesized via a simple precipitation method for photocatalytic degradation of tetracycline (TC) under visible light irradiation. The experimental result reveals that the ternary APO/CPO/CN heterojunction showed enhanced photocatalytic performance compared with single semiconductor CPO and CN, binary composite CPO/CN. And APO/CPO/CN-15 % composite exhibits highest photocatalytic degradation efficiency, which can degrade TC around 88 % under visible light within 120 min. The enhanced photocatalytic performance is due to the synergy effects between CPO, CN and APO with the aid of following Z-scheme and Type II heterojunction dual pathways for effective separation of photogenerated charges. This work provides a new approach in the rational design of ternary heterojunction photocatalyst with multilevel electron transfer for environmental decontamination.

An effective strategy for boosting photoinduced charge separation of Ag3PO4 by BiVO4 with enhanced visible light photodegradation efficiency for levofloxacin and methylene blue

In this paper, a Z-scheme Ag₃PO₄/BiVO₄ photocatalyst was successfully prepared by precipitation-deposition method. The Ag₃PO₄/BiVO₄ composite exhibited enhanced photocatalytic activity and recyclability for levofloxacin and methylene blue degradation under visible light irradiation. In the Ag₃PO₄/BiVO₄-0.4 system, up to 92.44% of the levofloxacin molecules can be decomposed within 180 min and the photocatalytic degradation efficiency can maintain at 92.02% for methylene blue after recycled for 5 times. The enhanced photocatalytic activity of Ag₃PO₄/BiVO₄ heterojunctions could be mainly attributed to the fabrication of hetero-structure between BiVO₄ and Ag₃PO₄. The photogenerated electron-hole pair separation was effectively enhanced based on the photocurrent, electro-chemical impedance spectra and photoluminescence data. Furthermore, the electrons transfer from photoinduced BiVO₄ to Ag₃PO₄ and the visible light harvesting efficiencies were significantly increased due to the BiVO₄ hybridization. The ·OH was the main oxidative species in the Ag₃PO₄/BiVO₄ system for the methylene blue decomposition. Finally, a purposed photocatalytic mechanism for methylene blue degradation was discussed in detail on the basis of experimental results.

Facile synthesis of new polyhedron-like WO3/butterfly-like Ag2MoO4 p–n junction photocatalysts with higher photocatalytic activity in UV/solar region light

A series of novel efficient polyhedron-like WO₃/butterfly-like Ag₂MoO₄ p–n junction photocatalysts (denoted as AMW-x) were designed and synthesized.

Facile fabrication of a NiO/Ag3PO4 Z-scheme photocatalyst with enhanced visible-light-driven photocatalytic activity

The photocatalytic performance of Z-scheme NiO/Ag/Ag₃PO₄ was evaluated by degrading organic pollutants under visible light.

Selective oxidation of alcohols by using CoFe2O4/Ag2MoO4 as a visible-light-driven heterogeneous photocatalyst

Using a CoFe₂O₄/Ag₂MoO₄ heterostructure as a novel, stable, inexpensive, and reusable photocatalyst with high-performance for the oxidation of alcohols.

A new biocompatible ternary Layered Double Hydroxide Adsorbent for ultrafast removal of anionic organic dyes

It would be of great significance to introduce a new biocompatible Layered Double Hydroxide (LDH) for the efficient remediation of wastewater. Herein, we designed a facile, biocompatible and environmental friendly layered double hydroxide (LDH) of NiFeTi for the very first time by the hydrothermal route. The materialization of NiFeTi LDH was confirmed by FTIR, XRD and Raman studies. BET results revealed the high surface area (106 m²/g) and the morphological studies (FESEM and TEM) portrayed the sheets-like structure of NiFeTi nanoparticles. The material so obtained was employed as an efficient adsorbent for the removal of organic dyes from synthetic waste water. The dye removal study showed >96% efficiency for the removal of methyl orange, congo red, methyl blue and orange G, which revealed the superiority of material for decontamination of waste water. The maximum removal (90%) of dyes was attained within 2 min of initiation of the adsorption process which supported the ultrafast removal efficiency. This ultrafast removal efficiency was attributed to high surface area and large concentration of -OH and CO₃²⁻ groups present in NiFeTi LDH. In addition, the reusability was also performed up to three cycles with 96, 90 and 88% efficiency for methyl orange. Furthermore, the biocompatibility test on MHS cell lines were also carried which revealed the non-toxic nature of NiFeTi LDH at lower concentration (100% cell viability at 15.6 μg/ml). Overall, we offer a facile surfactant free method for the synthesis of NiFeTi LDH which is efficient for decontamination of anionic dyes from water and also non-toxic.

Rodlike AgI/Ag2Mo2O7 Heterojunctions with Enhanced Visible-Light-Driven Photocatalytic Activity

Novel AgI/Ag2Mo2O7 heterojunctions were prepared by reacting Ag2Mo2O7 microrods with an aqueous KI solution at room temperature. The composite materials, compared with neat AgI and Ag2Mo2O7, showed much higher activities in the photocatalytic degradation of aqueous rhodamine B, methyl orange, tetracycline hydrochloride, and levofloxacin solutions under visible-light irradiation. The structures, morphologies, and other physicochemical properties of AgI, Ag2Mo2O7, and AgI/Ag2Mo2O7 composites were studied via various characterization techniques. The active species involved in the photocatalytic process were examined via radical-capturing experiments and electron spin resonance. Superoxide anion radicals (•O2 -) and photogenerated holes (h+) were found to be the main active species. Photocatalytic mechanisms were proposed and reasons for the enhanced photocatalytic activity were explained.

La- and Mn-Codoped Bismuth Ferrite/Ti3C2 MXene Composites for Efficient Photocatalytic Degradation of Congo Red Dye

Over the years, scarcity of fresh potable water has increased the demand for clean water. Meanwhile, with the advent of nanotechnology, the use of nanomaterials for photocatalytic degradation of pollutants in wastewaters has increased. Herein, a new type of nanohybrids of La- and Mn-codoped bismuth ferrite (BFO) nanoparticles embedded into transition-metal carbide sheets (MXene-Ti₃C₂) were prepared by a low-cost double-solvent sol-gel method and investigated for their catalytic activity in dark and photoinduced conditions. The photoluminescence results showed that pure BFO has the highest electron hole recombination rate as compared to all the codoped BFO/Ti₃C₂ nanohybrids. The higher electron-hole pair generation rate of the nanohybrids provides a suitable environment for fast degradation of organic dye molecules. The band gap of the prepared nanohybrid was tuned to 1.73 eV. Moreover, the BLFO/Ti₃C₂ and BLFMO-5/Ti₃C₂ degraded 92 and 93% of the organic pollutant, respectively, from water in dark and remaining in the light spectrum. Therefore, these synthesized nanohybrids could be a promising candidate for catalytic and photocatalytic applications in future.

High-yield lactic acid-mediated route for a g-C3N4 nanosheet photocatalyst with enhanced H2-evolution performance

Facile and novel strategies to prepare g-C3N4 nanosheets are required to greatly improve their photocatalytic H2-production activity. In this study, a lactic acid-mediated synthesis route has been developed to prepare g-C3N4 nanosheets, which includes the preassembled formation of lactic acid-melamine co-monomers, followed by direct high-temperature calcination. In this case, it is found that during high-temperature calcination, the lactic acid molecules can greatly prevent the serious polymerization of melamine molecules, resulting in the formation of g-C3N4 nanosheets. Moreover, owing to the strong coupling with melamine molecules, lactic acid can also significantly increase the production rate (ca. 35.16 wt%) of g-C3N4 nanosheets from the melamine precursor via preventing the rapid sublimation of melamine and its intermediates during the calcination progress compared with the well-known two-step calcination method. Photocatalytic experimental data reveal that the resultant g-C3N4 nanosheet photocatalysts show a greatly improved H2-production rate, and the g-C3N4 (500 μL) sample exhibits the best photocatalytic performance, which is obviously two times higher than that of the conventional bulk g-C3N4. In addition to lactic acid, it is very interesting to find that acetic acid can also be used to prepare g-C3N4 nanosheets via a similar formation mechanism, strongly suggesting the universality and versatility of the present lactic acid-mediated synthesis route. The present synthesis strategy may broaden the horizons for the synthesis of high-efficiency photocatalysts.

Hydrothermal synthesis of p-C3N4/f-BiOBr composites with highly efficient degradation of methylene blue and tetracycline

Construction of heterojunctions with band-suitable different semiconductors has been demonstrated to be an efficient approach to enhance the separation of photoinduced electrons and holes. In this paper, highly efficient heterojuction photocatalysts consisted of porous-C₃N₄ (p-C₃N₄) and flowerlike-BiOBr (f-BiOBr) were successfully synthesized via a deposition-hydrothermal method. The SEM and HRTEM images indicated that BiOBr were successfully deposited on the surface of p-C₃N₄ and the layered p-C₃N₄/f-BiOBr heterojunctions were formed between p-C₃N₄ and f-BiOBr. The optimum photocatalytic activity of the p-C₃N₄/f-BiOBr nanocomposites with weight ratio of 3%p-C₃N₄ exhibited dramatically improved visible-light photocatalytic activities with 98.42% and 94.25% degradation rates for methylene blue (MB) and tetracycline, respectively. The enhanced activity was mainly attributed to the unique heteojunction architecture, which creates large interfacial surface between the constituent materials for facilitating charge transfer and effectively inhibits the fast recombination of photogenerated electrons and holes. The active species trapping experiment indicated that the O₂^- was the dominating reactive oxidizing species of p-C₃N₄/f-BiOBr for MB degradation under visible light irradiation. Moreover, the as-prepared photocatalysts displayed excellent stability in the recycling experiments with no obvious decrease of the degradation efficiencies for MB and tetracycline. Furthermore, the possible photocatalytic degradation mechanism of MB over p-C₃N₄/f-BiOBr was proposed to better understand the reaction process. The work provides a facile route for rational design of heterojunction photocatalysts with promising prospect for the treatment of antibiotic residues in various wastewaters.

Visible-light degradation of sulfonamides by Z-scheme ZnO/g-C3N4 heterojunctions with amorphous Fe2O3 as electron mediator

ZnO grafted amorphous Fe₂O₃ matrix (ZnO/Fe₂O₃) was coupled with g-C₃N₄ to synthesize heterojunction photocatalysts with a loosened multilayered structure. The ZnO/Fe₂O₃/g-C₃N₄ exhibited enhanced photocatalytic performance in the degradation of sulfamethazine under visible-light irradiation (λ > 420 nm), with an optimum photocatalytic degradation rate approximately 3.0, 2.4 times that of pure g-C₃N₄ and binary ZnO/g-C₃N₄. Moreover, the target sulfonamides spiked in actual surface water samples could be efficiently photodegraded by ZnO/Fe₂O₃/g-C₃N₄ after 8 h of irradiation, demonstrating its practical potential. An amorphous Fe₂O₃-mediated Z-scheme mechanism was proposed for the charge transfer at the heterojunction surface, which involved a Fe(III)/Fe(II) oxidation-reduction center that favored the retarded charge recombination and improved photocatalytic activity. Such a mechanism was well supported by the direct detection of surface generated O₂^- and OH reactive species. Finally, detailed transformation pathways were proposed based on the photodegradation products identified by QToF-MS analyses. This work provides an illustrative strategy for developing efficient Z-scheme photocatalysts for water purification, by taking advantage of amorphous Fe-based oxides in the semiconductor lattice matching.

Titanium Phosphate Nanoplates Modified With AgBr@Ag Nanoparticles: A Novel Heterostructured Photocatalyst With Significantly Enhanced Visible Light Responsive Activity

AgBr@Ag modified titanium phosphate composites were fabricated through a two-step approach. The prepared samples were characterized by X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. The optical properties of the composites were characterized by using UV-vis diffuse reflectance spectroscopy. The photocatalytic activities of the composites were investigated on the degradation of Rhodamine B and ciprofloxacin under visible light irradiation. AgBr@Ag/titanium phosphate was determined to exhibit considerably higher photocatalytic activity than the corresponding individual components. The mechanism on the enhancement of the photocatalytic activity was proposed based on the results of photoluminescence spectra and photocurrent measurements. Furthermore, the possible photocatalytic mechanisms of organic compounds degradation were also proposed.

Antibiotic removal from water: A highly efficient silver phosphate-based Z-scheme photocatalytic system under natural solar light

Photocatalytic degradation is an alternative method to remove pharmaceutical compounds from water, however it is hard to achieve efficient rate because of the low efficiency of photocatalysts. In this study, an efficient Z-Scheme photocatalyst was constructed by integrating graphitic carbon nitride (CN) and reduced graphene oxide (rGO) with AP via a simple facile precipitation method. Excitedly, ternary AP/rGO/CN composite showed superior photocatalytic and anti-photocorrosion performances under both intense sunlight and weak indoor light irradiation. NOF can be completely degraded in only 30 min and about 85% of NOF can be mineralized after 2 h irradiation under intensive sunlight irradiation. rGO could work not only as a sheltering layer to protect AP from photocorrosion but also as a mediator for Z-Scheme electron transport, which can protect AP from the photoreduction. This strategy could be a promising method to construct photocatalytic system with high efficiency for the removal of antibiotics under natural light irradiation.

Ag2WO4 nanorods decorated with AgI nanoparticles: Novel and efficient visible-light-driven photocatalysts for the degradation of water pollutants

To develop efficient and stable visible-light-driven (VLD) photocatalysts for pollutant degradation, we synthesized novel heterojunction photocatalysts comprised of AgI nanoparticle-decorated Ag2WO4 nanorods via a facile method. Various characterization techniques, including XRD, SEM, TEM, EDX, and UV-vis DRS were used to investigate the morphology and optical properties of the as-prepared AgI/Ag2WO4 catalyst. With AgI acting as the cocatalyst, the resulting AgI/Ag2WO4 heterostructure shows excellent performance in degrading toxic, stable pollutants such as rhodamine B (RhB), methyl orange (MO) and para-chlorophenol (4-CP). The high performance is attributed to the enhanced visible-light absorption properties and the promoted separation efficiency of charge carriers through the formation of the heterojunction between AgI and Ag2WO4. Additionally, AgI/Ag2WO4 exhibits durable stability. The active species trapping experiment reveals that active species (O2•- and h+) dominantly contribute to RhB degradation. The AgI/Ag2WO4 heterojunction photocatalyst characterized in this work holds great potential for remedying environmental issues due to its simple preparation method and excellent photocatalytic performance.

Enhanced visible-light photocatalytic activity and photostability of Ag3PO4/Bi2WO6 heterostructures toward organic pollutant degradation and plasmonic Z-scheme mechanism

Novel Ag3PO4/Bi2WO6 heterostructured materials with enhanced visible-light catalytic performance were successfully synthesized by assembly combined with a hydrothermal treatment. The microstructures, morphologies, and optical properties of the prepared samples were characterized by multiple techniques. The irregular Ag3PO4 nanospheres dispersed on the surface of Bi2WO6 nanoflakes, and their catalytic performances were evaluated via the degradation of organic pollutants including rhodamine B (RB), methylene blue (MB), crystal violet (CV), methyl orange (MO), and phenol (Phen) under visible-light irradiation. The resulting Ag3PO4/Bi2WO6 heterostructured materials displayed higher photocatalytic activity than that of either pure Bi2WO6 or Ag3PO4. The enhanced photocatalytic activity was due to the good formation of heterostructures, which could not only broaden the spectral response range to visible light but also effectively promoted the charge separation. Meanwhile, the reasonable photoreactive plasmonic Z-scheme mechanism was carefully investigated on the basic of the reactive species scavenging tests, photoelectrochemical experiments, and photoluminescence (PL) spectrum. In addition, the excellent photostability of Ag3PO4/Bi2WO6 was obtained, which Ag formed at the early photocatalytic reaction acted as the charge transmission-bridge to restrain the further photoreduction of Ag3PO4.

Novel nanomagnetic Ag/β-Ag2WO4/CoFe2O4 as a highly efficient photocatalyst under visible light irradiation

The Ag/β-Ag₂WO₄/CoFe₂O₄ heterogeneous nanophotocatalyst exhibits high photocatalytic activity for the oxidation of alcohols and can be easily recycled using a permanent magnet. Also, the underlying mechanism for its activity is proposed.

Electron transportation path build for superior photoelectrochemical performance of Ag3PO4/TiO2

An efficient electron transportation path built through preparing Ag₃PO₄/TiO₂ heterojunction by dipping method. It has a higher photocurrent density of 2.34 mA cm⁻².