Preparation and characterization of Ag3PO4/BiOI composites with enhanced visible light driven photocatalytic performance

Ag₃PO₄/BiOI composites were successfully prepared by a facial room temperature liquid phase method. Ag₃PO₄ nanoparticles were uniformly distributed on the surface of BiOI nanosheets. The photodegradation tests show that the photocatalytic efficiency was increased at first and then decreased when further increasing Ag₃PO₄ content in the composites. The best photocatalytic performance was obtained for the sample with Ag/Bi ratio of 0.3 and the photodegradation efficiency of Ag₃PO₄/BiOI was nearly 10 times that of BiOI. The enhanced photocatalytic activity of the composites was due to the improved photogenerated carrier separation capacity, being induced by the coupling effects of the two semiconductors.     

Photocatalytic degradation of Basic Blue 41 dye under visible light over SrTiO3/Ag3PO4 hetero-nanostructures

In an attempt to develop nanostructured photocatalysts with high performance, SrTiO₃/Ag₃PO₄ hetero-nanostructures were successfully fabricated. The formed binary heterojunctions were composed of SrTiO₃ nanotubes prepared using liquid-phase deposition, and Ag₃PO₄ nanoparticles prepared using a sol–gel method. Synthesis details, including morphology, structure, and optical properties of the prepared photocatalysts, were characterized and comparatively discussed. The results showed that at an optimal ratio of SrTiO₃ to Ag₃PO₄ (20–80), the photocatalytic degradation of Basic Blue 41 under 80-min visible light irradiation is the maximum amount of 99%, which is about 4.4 and 1.5 times higher than that of pristine SrTiO₃ nanorods and Ag₃PO₄ nanoparticles, respectively. It can be due to the synergistic effect of two materials that provide high light absorption and charge carriers’ separation. Finally, a detailed possible mechanism for enhancing the photocatalytic activity of the SrTiO₃/Ag₃PO₄ hetero-nanostructures was proposed.     

BiOCl/Ag3PO4 Composites with Highly Enhanced Ultraviolet and Visible Light Photocatalytic Performances

The BiOCl/Ag₃PO₄ composites have been prepared via a facile and reproducible route. In the composite, Ag₃PO₄ particles are deposited on the surface of plates of BiOCl. Among the as‐prepared samples, the ultraviolet (UV) and visible light photocatalytic reaction rates of BiOCl/Ag₃PO₄ composite with the ratio of 1:0.1 are about 4.4 times and 4.5 times than that of pure BiOCl, respectively. Overall, the BiOCl/Ag₃PO₄ composites not only show highly enhanced visible light photocatalytic activity but also exhibit highly improved UV photocatalytic activity, which could find enormous potential application in addressing environmental protection issues utilizing solar energy effectively.     

Ultrasound-assisted synthesis of high-efficiency Ag3PO4/CeO2 heterojunction photocatalyst

The Ag₃PO₄/CeO₂ heterojunction photocatalyst prepared by an ultrasound-assisted method exhibits an enhanced photocatalytic activity compared to pure Ag₃PO₄, CeO₂, and Ag₃PO₄/CeO₂ obtained without ultrasound action. The samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and ultraviolet–visible absorption spectroscopy (UV–vis), and the effects of ultrasound on the physicochemical properties and photocatalytic activity of Ag₃PO₄/CeO₂ are discussed. Results show that the ultrasound-assisted synthesis method significantly improves the photocatalytic ability. The mechanism about the improvement was discussed in details.     

Facile synthesis of Ag3PO4 with the assistance of N,N-dimethylformamid and urea for high performance photocatalysis

Ag₃PO₄ was synthesized with the assistance of N, N-dimethylformamid (DMF) and urea for high performance photocatalysis. The photocatalytic activity of the as-synthesized samples was evaluated by photodegrading rhodamine B (Rh B) under visible light irradiation. As a result, the optimal Ag₃PO₄ synthesized with the assistance of DMF and urea exhibited enhanced photocatalytic activity for Rh B degradation under visible light irradiation. DMF and urea play vital roles in improving the photocatalytic activity of Ag₃PO₄. This study could provide a new perspective for the controllable synthesis of Ag₃PO₄.     

Ag3PO4 quantum dots loaded on the surface of leaf-like InVO4/BiVO4 heterojunction with enhanced photocatalytic activity

Leaf-like InVO₄/BiVO₄ nanoarchitectures with scale of 2 μm–5 μm were prepared by a facile hydrothermal method. Ag₃PO₄ quantum dots (QDs) were then deposited onto the surface of leaf-like InVO₄/BiVO₄ crystals via a simple deposition–precipitation technique. The photocatalytic tests displayed that the Ag₃PO₄/InVO₄/BiVO₄ nanocomposite possesses a much higher rate for degradation of rhodamine B (Rh B) than the sum of BiVO₄, InVO₄, Ag₃PO₄, Ag₃PO₄/InVO₄, Ag₃PO₄/BiVO₄ or InVO₄/BiVO₄ under visible light irradiation. The observed improvement in photocatalytic performance is associated with the extended absorption in the visible light region resulting from the Ag₃PO₄ QD loading, the high specific surface area, and the effective separation of photogenerated carriers at the Ag₃PO₄/InVO₄/BiVO₄ interfaces.     

In-situ deposition of Ag3PO4 on TiO2 nanosheets dominated by (001) facets for enhanced photocatalytic activities and recyclability

Ag₃PO₄/TiO₂ nanosheet (TNS) heterojunction photocatalysts with almost 100% exposed (001) facets were fabricated via a facile in situ growth process. The Ag₃PO₄/TNS exhibited remarkable photocatalytic activity for the degradation of rhodamine B (RhB) and it was significantly more recyclable under sunlight compared with Ag₃PO₄. The RhB degradation efficiency was 99.11% after 50 min of sunlight irradiation, and was 85.8% after three cycles. The photocatalytic degradation mechanism of RhB over the Ag₃PO₄/TNS heterojunctions is driven by both photogenerated holes (h⁺) and ·O₂⁻ radicals. This efficient and reusable Ag₃PO₄/TNS heterojunction photocatalyst is not only suitable for fundamental research but also has potential for practical applications in the energy and environmental fields. This study demonstrates that applying morphology engineering to heterojunctions is useful for developing composite photocatalysts with greatly improved properties.     

The stabilization effect of surface capping on photocatalytic activity and recyclable stability of Ag3PO4

We find the stabilization effect of surface capping on the adsorption capacity and photocatalytic activity of Ag₃PO₄ in the recycling. The citrate anion complex (CAC) as the surface capping is confirmed to be constituted by citrate anion and silver citrate complex. The adsorption capacity of Ag₃PO₄ with CAC capping exhibits little increase in the subsequent cycle, whereas the one of the bare Ag₃PO₄ decreases by 25.8% for methylene blue (MB). The photocatalytic activity of Ag₃PO₄ with CAC capping is maintained, compared to marked 10% decrease of bare Ag₃PO₄ for degrading MB.     

Construction of g-C3N4 nanotube/Ag3PO4 S-scheme heterojunction for enhanced photocatalytic oxygen generation

Heterojunction engineering is considered as a hopeful approach to ameliorate the separation of photogenerated carriers of photocatalysts, realizing efficient water-splitting performance. In this study, an organic-inorganic S-scheme of a one-dimensional g-C₃N₄ nanotube (TCN)/Ag₃PO₄ photocatalytic system with high photocatalytic water oxidation activity was designed by coupling g-C₃N₄ nanotubes over Ag₃PO₄ particles through a chemical coprecipitation method. The TCN/Ag₃PO₄ heterojunction demonstrated excellent photocatalytic O₂ production with an O₂ evolution rate of up to 370.2 μmol·L^?1·h^?1. X-ray photoelectron spectroscopy analysis showed that electron migration between TCN and Ag₃PO₄ led to the formation of an internal electric field pointing from TCN to Ag₃PO₄, which drove the S-scheme charge transfer mode between TCN and Ag₃PO₄. Accordingly, the TCN/Ag₃PO₄ heterojunction possessed fast charge separation and high redox ability, leading to high photoactivity and photostability. This research provides a new strategy for fabricating highly efficient inorganic-organic S-scheme photocatalysts for O₂ production.     

Z-scheme AgSCN/Ag3PO4/C3N4 heterojunction with excellent photocatalytic degradation of ibuprofen

To develop a novel photocatalyst with high catalytic performance under sunlight, AgSCN/Ag₃PO₄/C₃N₄ heterojunction photocatalyst with Z-mechanism has been prepared, which demonstrates excellent photocatalytic performance for ibuprofen degradation. The catalytic activity of AgSCN/Ag₃PO₄/C₃N₄ is 1.5 and 3.3 times that of AgSCN/Ag₃PO₄ and Ag₃PO₄, respectively. The cyclic degradation number of AgSCN/Ag₃PO₄/C₃N₄ increases to seven because of the protection of AgSCN and C₃N₄ to Ag₃PO₄. The excellent photocatalytic performance of the AgSCN/Ag₃PO₄/C₃N₄ is attributed from the Z-mechanism with efficient separation efficiency of electron hole pair.     

Ag3PO4/Bi2WO6 hierarchical heterostructures with enhanced visible light photocatalytic activity for the degradation of phenol

The Ag₃PO₄/Bi₂WO₆ hierarchical heterostructures were prepared by a combination of hydrothermal technique and in situ precipitation method for the first time. The Ag₃PO₄/Bi₂WO₆ hierarchical heterostructures displayed enhanced visible-light photocatalytic activity against phenol. The enhanced photocatalytic activity could be attributed to the effective separation of photogenerated carriers driven by the photoinduced potential difference generated at the Ag₃PO₄/Bi₂WO₆ heterojunction interface. Repetitive tests showed that the Ag₃PO₄/Bi₂WO₆ hierarchical heterostructures maintained high catalytic activity over several cycles, and it had a better regeneration capability under mild conditions.     

Highly efficient and stable Ag/Ag3PO4 plasmonic photocatalyst in visible light

A highly efficient and stable photocatalyst Ag/Ag₃PO₄ was prepared by the ion-exchange process between AgNO₃ and Na₂HPO₄ and subsequently light-induced reduction route. The diffuse reflectance spectra (DRS) indicated Ag/Ag₃PO₄ had strong absorption in UV and visible-light regions. The composite showed excellent visible-light-driven photocatalytic performance. It can decompose organic dye within several minutes and still maintain a high level activity even though used five times. It is considered that this excellent performance results from the surface plasmon resonance of Ag nanoparticles and a large negative charge of PO₄^3 − ions.     

A g-C3N4 supported graphene oxide/Ag3PO4 composite with remarkably enhanced photocatalytic activity under visible light

In this work, a ternary composite photocatalyst of graphitic carbon nitride (g-C₃N₄), graphene oxide (GO), and Ag₃PO₄ was prepared through a simple precipitation route, in which Ag₃PO₄ nanoparticles covered or wrapped with GO sheets are supported on g-C₃N₄ sheets. The composite photocatalyst displays enhanced absorption in the visible region, and exhibited superior photocatalytic activity compared with single-component or binary composite photocatalysts in the photocatalytic decomposition of Rhodamine B. The enhancement of photocatalytic activity could be attributed to the synergistic effect among them. The ternary composite also exhibited enhanced stability, but further efforts should be made to make it more stable.     

Porous Ag3PO4 microtubes with improved photocatalytic properties

The Ag₃PO₄ porous microtubes are, for the first time, prepared by a one-pot synthesis using polyethylene glycol 200 (PEG200) as the reaction medium. This study establishes that PEG 200 plays a vital role in the formation of the unique structures. Under visible light irradiation (≥ 420 nm), the porous sample exhibits a higher photocatalytic activity for the degradation of RhB than solid Ag₃PO₄ and Ag₃PO₄ tetrapods, which has been mainly ascribed to the novel hollow structure.     

Dual Z-scheme heterojunction g-C3N4/Ag3PO4/AgBr photocatalyst with enhanced visible-light photocatalytic activity

Recently, there has been a significant interest in developing high-performance photocatalysts for removing organic pollutants from water environment. Herein, a ternary graphitic C₃N₄ (g-C₃N₄)/Ag₃PO₄/AgBr composite photocatalyst is synthesized using an in-situ precipitation-anion-exchange process and characterized by several spectroscopic and microscopic techniques. During the photocatalytic reaction, X-ray photoelectron spectroscopy clearly illustrated the formation of metallic Ag on the g-C₃N₄/Ag₃PO₄/AgBr composite surface. The ternary composite photocatalyst demonstrated an increased photoactivity under visible light (>420 nm), achieving a complete decolorization of methyl orange (MO) in 5 min. The ternary g-C₃N₄/Ag₃PO₄/AgBr hybrid was also applied to the 2-chlorophenol degradation under visible light, further confirming its excellent photocatalytic activity. In addition, quenching experiments revealed that holes (h⁺) and O₂^?– were the major attack species in the decolorization of MO. The enhanced photoactivity of g-C₃N₄/Ag₃PO₄/AgBr results from the efficient transfer/separation of photoinduced charges with the dual Z-scheme pathway and the charge recombination sites on the formed Ag particles.     

Photocatalytic degradation of bisphenol A by Ag3PO4 under visible light

Ag₃PO₄ catalysts exhibited excellent photocatalytic performance in the degradation and the mineralization of bisphenol A, displaying considerably higher photocatalytic activity than N–TiO₂ under visible light (λ > 420 nm). The trapping effects of different scavengers and spectrophotometric results proved that the oxidation of bisphenol A mainly occurred at photogenerated holes on the Ag₃PO₄ surface, along with a two-electron reduction of dissolved oxygen to H₂O₂.     

Fabrication and photocatalytic performance of one-dimensional Ag3PO4 sensitized SrTiO3 nanowire

The 1D Ag₃PO₄ sensitized SrTiO₃ nanowires are prepared by simple route of electrospinning-in situ deposition technique. The results of the thermogravimetry (TG), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive Spectrometer (EDS), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and UV–Visible diffuse reflectance spectroscopy (UV–Vis) indicate that the Ag₃PO₄ nanoparticles has been deposited on the surface of the SrTiO₃ nanowires successfully. Experimental results showed that compared with pure SrTiO₃, the as-prepared 1D Ag₃PO₄ sensitized SrTiO₃ nanowires exhibit obvious enhancement of photocatalytic performance and stability. Especially, the Ag₃PO₄/SrTiO₃ (3AS sample) had a satisfactory photocatalytic activity for degrading methylene blue (MB) more than 98% under visible light irradiation. As to pure SrTiO₃ and Ag₃PO₄, only 9.8% and 49% of MB was decomposed after 35?min irradiation respectively. Furthermore, the mechanism of the enhancing photocatalytic activity could be ascribed to the nano-heterojunction of the Ag₃PO₄/SrTiO₃, the visible light response of the Ag₃PO₄, and the 1D structure of the nanowires.     

Photocatalytic activity of Ag3PO4 and some of its composites under non-filtered and UV-filtered solar-like radiation

Silver phosphate is a promising photocatalyst since its energy band gap is situated in the visible range (E_g≈2.4 eV), thus this material is a potential candidate for replacing titania which is photoactive only under UV. However, Ag₃PO₄ suffers of photocorrosion and therefore composites should be prepared to limit this detrimental effect. In this work, pure Ag₃PO₄ and its composites with AgI, TiO₂, and hydroxyapatite were prepared by using various methods. The photoactivity of the materials was evaluated by their ability to decolorize methylene blue and to mineralize phenol under non-filtered and UV-filtered artificial solar-like radiation. The use of UV cut-off filter enhanced the photocatalytic activity of pure silver phosphate by limiting the photocorrosion of silver(I) into Ag°. For composites with AgI and TiO₂, despite their lower photoactivity compared to pure Ag₃PO₄, the efficiency in mineralization of phenol after repeated run is stabilized by using UV cut-off filter. On the other hand, the photocatalytic efficiency of Ag₃PO₄ composites containing hydroxyapatite remained low mainly due to high absorption properties of hydroxyapatite. The photoactive samples showed excellent photoinduced antimicrobial properties where Gram-negative E. coli was more susceptible to photocatalytic deactivation than Gram-positive S. aureus (MRSA).     

The highly active saddle-like Ag3PO4 photocatalyst under visible light irradiation

Saddle-like Ag₃PO₄ particles of tetrahedron structure were successfully synthesized using a co-precipitation method by mixing H₃PO₄ ethanol solution and AgNO₃ ethanol aqueous solution, where the percentage of ethanol in AgNO₃ ethanol aqueous solution was varied at 0, 50, 80, 90 and 100% (v/v). The photocatalytic performance of the synthesized samples was evaluated by photodegradation of Rhodamine B (RhB) under blue light irradiation (λ = 455 nm). The results showed that the morphology of the Ag₃PO₄ particles greatly changed depending on the ethanol content in the reaction solution. Excellent photocatalytic activity was observed at 80% (v/v) of ethanol, where the Ag₃PO₄ showed saddle-like morphology derived from the tetrahedron structure.     

Facile synthesis of visible-light-driven Ag3PO4 nanocrystals base on IP6 micelles

A simple, environment-friendly and easily operating strategy, inositol hexaphosphoric sodium assisted soft template method, has been developed for synthesis of uniform Ag₃PO₄ nanocrystals (NCs) with controlled size in the range of 40 to 50 nm. The Ag₃PO₄ NCs exhibit superior photocatalytic activity compared with micron-sized Ag₃PO₄ particles under visible light. This approach is a general method and can be extended to the synthesis of a variety of other silver salts NCs.