Single-atom Ag-loaded carbon nitride photocatalysts for efficient degradation of acetaminophen: The role of Ag-atom and O2

Carbon nitride has been extensively used as a visible-light photocatalyst, but it has the disadvantages of a low specific surface area, rapid electron-hole recombination, and relatively low light absorbance. In this study, single-atom Ag was successfully anchored on ultrathin carbon nitride (UTCN) via thermal polymerization, the catalyst obtained is called AgUTCN. The Ag hardly changed the carbon nitride's layered and porous physical structure. AgUTCN exhibited efficient visible-light photocatalytic performances in the degradation of various recalcitrant pollutants, eliminations of 85% were achieved by visible-light irradiation for 1 hr. Doping with Ag improved the photocatalytic performance of UTCN by narrowing the forbidden band gap from 2.49 to 2.36 eV and suppressing electron-hole pair recombination. In addition, Ag doping facilitated O2 adsorption on UTCN by decreasing the adsorption energy from -0.2 to -2.22 eV and favored the formation of O2·-. Electron spin resonance and radical-quenching experiments showed that O2·- was the major reactive species in the degradation of Acetaminophen (paracetamol, APAP).

Dual-functional marine algal carbon-based materials with highly efficient dye removal and disinfection control

The design and simple, green preparation of dual-functional materials for the decontamination of both hazardous dyes and pathogenic microorganisms from wastewater remain challenging currently. Herein, a promising marine algal carbon-based material (named C-SA/SP) with both highly efficient dye adsorptive and antibacterial properties was fabricated based on the incorporation of sodium alginate and a low dose of silver phosphate via a facile and eco-friendly approach. The structure, removal of malachite green (MG) and congo red (CR), and their antibacterial performance were studied, and the adsorption mechanism was further interpreted by the statistical physics models, besides the classic models. The results show that the maximum simulated adsorption capacity for MG reached 2798.27 mg/g, and its minimal inhibit concentration for Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) was 0.4 mg/mL and 0.2 mg/mL, respectively. The mechanistic study suggests that silver phosphate exerted the effects of catalytic carbon formation and pore formation, while reducing the electronegativity of the material as well, thus improving its dye adsorptive performance. Moreover, the MG adsorption onto C-SA/SP showed vertical orientation and a multi-molecular way, and its adsorption sites were involved in the adsorption process with the increase of temperature. Overall, the study indicates that the as-made dual-functional materials have good applied prospects for water remediation.

Subsurface oxygen defects electronically interacting with active sites on In2O3 for enhanced photothermocatalytic CO2 reduction

Oxygen defects play an important role in many catalytic reactions. Increasing surface oxygen defects can be done through reduction treatment. However, excessive reduction blocks electron channels and deactivates the catalyst surface due to electron-trapped effects by subsurface oxygen defects. How to effectively extract electrons from subsurface oxygen defects which cannot directly interact with reactants is challenging and remains elusive. Here, we report a metallic In-embedded In₂O₃ nanoflake catalyst over which the turnover frequency of CO₂ reduction into CO increases by a factor of 866 (7615 h⁻¹) and 376 (2990 h⁻¹) at the same light intensity and reaction temperature, respectively, compared to In₂O₃. Under electron-delocalization effect of O-In-(O)V_o-In-In structural units at the interface, the electrons in the subsurface oxygen defects are extracted and gather at surface active sites. This improves the electronic coupling with CO₂ and stabilizes intermediate. The study opens up new insights for exquisite electronic manipulation of oxygen defects.

How to effectively extract electrons from subsurface oxygen defects is challenging in heterogeneous catalysis. Here the authors demonstrate that Metallic In-embedded In2O3 nanoflake catalyst promotes the delocalization of electrons among subsurface oxygen defects, obviously increasing electron density of surface active sites.

Enhancing the antifouling and rejection properties of PVDF membrane by Ag3PO4-GO modification

Ultrafiltration is an environmentally friendly water treatment technology, but membrane fouling significantly impacts membrane performance and service life. Photocatalytic modification of membrane is regarded as an effective way for membrane fouling control. In this study, graphite oxide (GO), Ag₃PO₄ and Ag₃PO₄-GO nanomaterials were applied in polyvinylidene fluoride (PVDF) ultrafiltration membranes modification, and the membranes was denoted as P-GO, P-AgP and P-AgP@GO, respectively. Filtration of humic acid (HA) at different operating conditions was adopted in evaluation of membrane performance. Among them, P-AgP@GO had the best permeation, rejection and antifouling performances, and could maintain excellent properties when operation conditions (HA concentration, operation pressure, pH and ionic strength) were changed. Furthermore, the effect of photocatalysis on the self-cleaning performance and its mechanism were revealed. The overall performance of P-AgP@GO could be enhanced by visible light irradiation, and extending the visible illumination time during the filtration was conducive to the reusability.

Piezoelectric polarization modulated novel Bi2WO6/g-C3N4/ZnO Z-scheme heterojunctions with g-C3N4 intermediate layer for efficient piezo-photocatalytic decomposition of harmful organic pollutants

It is of great significance to understand the role of carrier in piezocatalysis of composites by studying the separation mode of carriers under dynamic polarization field. Herein, the separation and migration pathways of carriers under piezoelectric field are investigated by synthesizing heterojunctions with Bi₂WO₆ (BWO) nanosheets grown vertically on g-C₃N₄ (CN) coated ZnO nanorods and directly on ZnO. Compared with the photocatalysis, the piezocatalytic efficiency of Rhodamine B (RhB) by BWO/ZnO is significantly increased to 0.121 min^-1, which indicated the polarization field promotes band tilt and Z-scheme formation. After introducing the CN interlayer, the piezocatalytic efficiency of BWO/CN/ZnO is further improved (0.217 min^-1), which can be attributed to the unique core-shell structure with Z-scheme heterojunctions. This unique structure provides more active sites and excited carrier concentration, the intermediate layer CN also reduces the direct contact and recombination of electrons and holes controlled by polarization potential at the interface between BWO and ZnO. This work deeply analyzes the influence of carrier concentration, separation efficiency and transport process on piezocatalysis, which provides a reference for the design of efficient catalysts.

Facile strategy for the fabrication of noble metal/ZnS composites with enhanced photocatalytic activities

The introduction of noble metal nanoparticles to photocatalysts can effectively improve the separation efficiency of the photogenerated electron–holes. Therefore, noble metal/ZnS composites were synthesized using a low-temperature solid-phase chemical method with sodium borohydride as the reducing agent. The characterization results showed that the noble metal/ZnS composites have been successfully obtained and that the noble metals were distributed on the surface of ZnS. The catalytic results suggested that the composites exhibited improved activity after introduction of noble metals, which can be attributed to the rapid migration of carriers and the enhancement of the light absorption, mainly owing to the tight combination between the ZnS and noble metals and the plasmon resonance effect of the noble metals. The catalytic mechanism was explored by using photoluminescence spectroscopy, photocurrent spectra, valence band X-ray photoelectron spectroscopy (XPS-VB) spectra and capture agent experiments, and a possible mechanism was proposed. This work provides a new strategy for the high-volume synthesis of noble metal-based composite photocatalysts, which could be helpful for sustainable development.

The introduction of noble metal nanoparticles to photocatalysts can effectively improve the separation efficiency of the photogenerated electron–holes.

Nanowire Genome: A Magic Toolbox for 1D Nanostructures

1D nanomaterials with high aspect ratio, i.e., nanowires and nanotubes, have inspired considerable research interest thanks to the fact that exotic physical and chemical properties emerge as their diameters approach or fall into certain length scales, such as the wavelength of light, the mean free path of phonons, the exciton Bohr radius, the critical size of magnetic domains, and the exciton diffusion length. On the basis of their components, aspect ratio, and properties, there may be imperceptible connections among hundreds of nanowires prepared by different strategies. Inspired by the heredity system in life, a new concept termed the "nanowire genome" is introduced here to clarify the relationships between hundreds of nanowires reported previously. As such, this approach will not only improve the tools incorporating the prior nanowires but also help to precisely synthesize new nanowires and even assist in the prediction on the properties of nanowires. Although the road from start-ups to maturity is long and fraught with challenges, the genetical syntheses of more than 200 kinds of nanostructures stemming from three mother nanowires (Te, Ag, and Cu) are summarized here to demonstrate the nanowire genome as a versatile toolbox. A summary and outlook on future challenges in this field are also presented.

Facile controlled synthesis of Ag3PO4 with various morphologies for enhanced photocatalytic oxygen evolution from water splitting

A facile and green hydrothermal method has been developed for the synthesis of Ag3PO4 with a variety of morphologies, including cubic, rhombic dodecahedral, spherical and roughly spherical, by using Ag4P2O7 as a sacrificial precursor. The as-prepared catalysts were characterized by carrying out X-ray diffraction (XRD), scanning electron microscopy (SEM), UV-visible diffuse reflectance spectroscopy (UV-Vis DRS), Fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS). The morphology of Ag3PO4 was controlled by simply adjusting the hydrothermal reaction temperature and time, without adding any templates and organic additives. Kinetics studies and characterization results revealed that the transformation from P2O7 4- to a PO4 3- radical was a rate-determining step, and influenced the morphology of Ag3PO4. Different oxygen evolution rates were observed for samples subjected to different hydrothermal reaction times, and the highest initial rate of O2 evolution achieved was 582.55 μmol h-1 g-1. Furthermore, for the samples prepared using a hydrothermal reaction time of 96 h, as the hydrothermal reaction temperature was increased, the oxygen evolution rate of the resulting sample decreased first and then increased, and the highest initial rate of O2 evolution was 856.06 μmol h-1 g-1, about twice the 418.34 μmol h-1 g-1 value for the sample prepared using the coprecipitation method. A possible mechanism has been proposed to explain how the hydrothermal reaction temperature and time influenced the Ag3PO4 morphology. Our method provides a guiding hydrothermal strategy for the synthesis of insoluble electrolytes with various morphologies from relatively soluble electrolytes without the need to use templates and organic additives.

One dimensional hierarchical nanostructures composed of CdS nanosheets/nanoparticles and Ag nanowires with promoted photocatalytic performance

One dimensional Ag@CdS core–shell hierarchical nanostructures with excellent photocatalytic performance have been fabricated via a simple wet-chemistry approach at low temperature.

Z-scheme Ag3PO4/POM/GO heterojunction with enhanced photocatalytic performance for degradation and water splitting

To develop solar light-driven photocatalysts with high activity and structural stability, Ag₃PO₄/POM/GO heterojunction has been successfully prepared by a facile method at room temperature.

Fabrication of Ag3PO4/GO/NiFe2O4 composites with highly efficient and stable visible-light-driven photocatalytic degradation of rhodamine B

Effective visible-light-driven Ag₃PO₄/GO/NiFe₂O₄Z-scheme magnetic composites were successfully fabricated by a simple ion-exchange deposition method. The Ag₃PO₄/GO/NiFe₂O₄ (8%) composite exhibited excellent photocatalytic activity (degradation efficiency was ∼96% within 15 min and kinetic constant reached 0.1956 min⁻¹) and stability when compared to Ag₃PO₄, NiFe₂O₄, and Ag₃PO₄/NiFe₂O₄ for rhodamine B (RhB) degradation. Furthermore, by electrochemical and fluorescence measurements, the Ag₃PO₄/GO/NiFe₂O₄ (8%) material also showed larger transient photocurrent, lower impedance, and longer fluorescence lifetime (7.82 ns). Comparing the activity result dependence with characterization results, it was indicated that photocatalytic activity depended on fast charge transfer from Ag₃PO₄ to NiFe₂O₄ through GO sheet. The h⁺ and ·O₂⁻ species played important roles in RhB degradation under visible-light. A possible Z-scheme mechanism is proposed over the Ag₃PO₄/GO/NiFe₂O₄ (8%) composite. This study might provide a promising visible light responsive photocatalyst for the photocatalytic degradation of organic dyes in wastewater.

Effective visible-light-driven Ag₃PO₄/GO/NiFe₂O₄Z-scheme magnetic composites were successfully fabricated by a simple ion-exchange deposition method. The composites exhibited excellent photocatalytic activity and stability for RhB degradation.

Rational design of a novel quaternary ZnO@ZnS/Ag@Ag2S nanojunction system for enhanced photocatalytic H2 production

A novel ZnO@ZnS/Ag@Ag₂S quaternary nanojunction photocatalyst has been designed for efficient solar water splitting.

A comprehensive understanding of water photooxidation on Ag3PO4 surfaces

A systematic study of the mechanism of OER on Ag₃PO₄ surfaces by combining hybrid DFT calculations and first principles thermodynamics.

Photocatalytic pathway toward degradation of environmental pharmaceutical pollutants: structure, kinetics and mechanism approach

During the last few years, the presence of pharmaceuticals in the aquatic environment, classified as so-called emerging contaminants, has attracted attention from the scientific community.

New insights into high temperature hydrothermal synthesis in the preparation of visible-light active, ordered mesoporous SiO2–TiO2 composited photocatalysts

Carbon doped, visible light active and ordered mesoporous TiO₂–SiO₂ nanocomposites have been successfully synthesized via one step high temperature (180 °C) hydrothermal technology.

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.

Synergistic effect of CoPi-hole and Cu(ii)-electron cocatalysts for enhanced photocatalytic activity and photoinduced stability of Ag3PO4

CoPi–Cu(ii)/Ag₃PO₄ not only exhibited much higher photocatalytic activity than Ag₃PO₄, Cu(ii)/Ag₃PO₄ and CoPi/Ag₃PO₄ but could also maintain excellently stable performance.

Biomimetic synthesis of Ag3PO4-NPs/Cu-NWs with visible-light-enhanced photocatalytic activity for degradation of the antibiotic ciprofloxacin

Cu-NWs/Ag₃PO₄-NPs can be used as photocatalysts under visible light irradiation and have high photocatalytic performance for degradation of CPFX.

Origin of Activity and Stability Enhancement for Ag₃PO₄ Photocatalyst after Calcination

Pristine Ag₃PO₄ microspheres were synthesized by a co-precipitation method, followed by being calcined at different temperatures to obtain a series of calcined Ag₃PO₄ photocatalysts. This work aims to investigate the origin of activity and stability enhancement for Ag₃PO₄ photocatalyst after calcination based on the systematical analyses of the structures, morphologies, chemical states of elements, oxygen defects, optical absorption properties, separation and transfer of photogenerated electron-hole pairs, and active species. The results indicate that oxygen vacancies (VO˙˙) are created and metallic silver nanoparticles (Ag NPs) are formed by the reaction of partial Ag⁺ in Ag₃PO₄ semiconductor with the thermally excited electrons from Ag₃PO₄ and then deposited on the surface of Ag₃PO₄ microspheres during the calcination process. Among the calcined Ag₃PO₄ samples, the Ag₃PO₄-200 sample exhibits the best photocatalytic activity and greatly enhanced photocatalytic stability for photodegradation of methylene blue (MB) solution under visible light irradiation. Oxygen vacancies play a significantly positive role in the enhancement of photocatalytic activity, while metallic Ag has a very important effect on improving the photocatalytic stability. Overall, the present work provides some powerful evidences and a deep understanding on the origin of activity and stability enhancement for the Ag₃PO₄ photocatalyst after calcination.

Bifunctional Ag/C3N4.5 composite nanobelts for photocatalysis and antibacterium

Multiple functions can be achieved in carbon nitride-based composite nanomaterials by tuning their components and structures. Here, we report on a large-scale synthesis of novel bifunctional Ag/C3N4.5 composite nanobelts (CNBs) with efficient photocatalytic and antibacterial activity. The Ag/C3N4.5 CNBs were synthesized in high yield by a two-step route including a homogeneous precipitation process and a subsequent calcination treatment. The structural, morphological, compositional, and spectroscopic characterizations revealed that the Ag/C3N4.5 CNBs are composed of N-deficient melem ultrathin nanobelts and crystalline Ag nanoparticles attached to the surface of the nanobelts with good contact. The band gap of the Ag/C3N4.5 CNBs is determined to be about 3.04 eV. The efficient photocatalytic and antibacterial activities of the composite nanomaterials are verified by testing the degradation of Rhodamine B (RhB) and the inhibition zone to bacterium E. coli. The work provides a facile route to bifunctional carbon nitride-based composites with potential applications in the fields of the environment and biology.

Fast Photoconductive Responses in Organometal Halide Perovskite Photodetectors

Inorganic semiconductor-based photodetectors have been suffering from slow response speeds, which are caused by the persistent photoconductivity of semiconductor materials. For realizing high speed optoelectronic devices, the organometal halide perovskite thin films were applied onto the interdigitated (IDT) patterned Au electrodes, and symmetrical structured photoconductive detectors were achieved. The detectors were sensitive to the incident light signals, and the photocurrents of the devices were 2-3 orders of magnitude higher than dark currents. The responsivities of the devices could reach up to 55 mA W(1-). Most importantly, the detectors have a fast response time of less than 20 μs. The light and bias induced dipole rearrangement in organometal perovskite thin films has resulted in the instability of photocurrents, and Ag nanowires could quicken the process of dipole alignment and stabilize the photocurrents of the devices.

Efficient visible driven photocatalyst, silver phosphate: performance, understanding and perspective

Photocatalysis is a promising technology that can contribute to renewable energy production from water and water purification. In order to further develop the field and meet industrial requirements, it is imperative to focus on advancing high efficiency visible light photocatalysts, such as silver phosphate (Ag3PO4). This review aims to highlight the recent progress made in the field, focusing on oxygen production from water, and organic contaminant decomposition using Ag3PO4. The most important advances are discussed and explained in detail, including semiconductor-semiconductor junctions, metal-semiconductor junctions, exposing facet control, and fundamental understanding using advanced spectroscopies and computational chemistry. The review then concludes by critically summarising both findings and current perspectives, and ultimately how the field might best advance in the near future.

Cu-doped mesoporous graphitic carbon nitride for enhanced visible-light driven photocatalysis

A series of Cu-doped mesoporous graphitic carbon nitride (Cu/mpg-C₃N₄) photocatalysts with Cu introduced from 0.1 to 5 wt% were prepared using cupric chloride and melamine as precursors.

Facile synthesis of porous Ag3PO4 photocatalysts with high self-stability and activity

1D Ag₃PO₄ hollow porous microrods have been fabricated with Ag₂WO₄ as growth templates, which exhibit enhanced photocatalytic activity and stability for the degradation of organic contaminations compared with Ag₃PO₄ cubes and particles.

ZnWO4/Ag3PO4 composites with an enhanced photocatalytic activity and stability under visible light

A simple and renewable approach to synthesize ZnWO₄/Ag₃PO₄ composites has been explored for the enhancement of the photocatalytic activity and stability of Ag₃PO₄.

UV-visible and near-infrared active NaGdF4:Yb:Er/Ag/TiO2 nanocomposite for enhanced photocatalytic applications

A near infra-red (NIR) active NaGdF₄:Yb:Er/Ag/TiO₂ nanocomposite photocatalyst was successfully synthesized by a one-pot thermal decomposition method.

Synthesis of Ag/Ag2CO3 heterostructures with high length–diameter ratios for excellent photoactivity and anti-photocorrosion

Ag/Ag₂CO₃ heterostructures with high length–diameter ratios and superior photoactivity and stability are synthesized on a large scale by a simple one-pot method.

A simple method of growing silver chloride nanocubes on silver nanowires

The growth of AgCl nanocubes directly on the sidewalls of Ag nanowires is demonstrated. The nanocubes can be simply obtained through extended low temperature annealing of polyol-synthesized silver nanowires in a vacuum. The length of time and temperature of the anneal and the diameter of the nanowire affect the size and density of the nanocubes obtained. It is hypothesized that the AgCl material is supplied from reactants leftover from the silver nanowire synthesis. This novel hybrid nanostructure may have applications in areas such as photovoltaics, surface enhanced Raman spectroscopy, and photocatalysis.

Photocatalytic Performances of Ag3PO4 Polypods for Degradation of Dye Pollutant under Natural Indoor Weak Light Irradiation

It is still a big challenge for Ag3PO4 to be applied in practice mainly because of its low stability resistant to photo corrosion, although it is an efficient photocatalyst. Herein, we have mainly investigated its activity and stability under indoor weak light for the degradation of dye pollutants. It is amazing that under indoor weak light irradiation, rhodamine B (RhB) can be completely degraded by Ag3PO4 polypods after 36 h, but only 18% of RhB by N-doped TiO2 after 120 h. It is found that under indoor weak light irradiation, the degradation rate (0.08099 h(-1)) of RhB over Ag3PO4 polypods are 46 times higher than that (0.00173 h(-1)) of N-doped TiO2. The high activity of Ag3PO4 polypods are mainly attributed to the three-dimensional branched nanostructure and high-energy {110} facets exposed. After three cycles, surprisingly, Ag3PO4 polypods show a high stability under indoor weak light irradiation, whereas Ag3PO4 have been decomposed into Ag under visible light irradiation with an artificial Xe light source. This natural weak light irradiation strategy could be a promising method for the other unstable photocatalysts in the degradation of environmental pollutants.

Co(II)-grafted Ag3PO4 photocatalysts with unexpected photocatalytic ability: Enhanced photogenerated charge separation efficiency, photocatalytic mechanism and activity

Since the photocatalytic capability is determined by the separation and transmission efficiency of photoinduced charges, its improvement remains a challenge for development of efficient photocatalysts. Here, we made large improvement on the surface of Ag3PO4 using Co(II)-grafted Ag3PO4 by a hydrothermal method. During the photocatalytic process, Co(II) was oxidized to Co(III) by the photogenerated holes under visible light radiation, which enhanced the separation efficiency of photogenerated charges. Meanwhile, the Co(III) as-formed could oxidize dye molecules, which recovered the Co(II). The synergy of Co(II) and Ag3PO4 greatly promoted the separation and transmission efficiency of the photogenerated charges, and severely improved the photocatalytic activity of Ag3PO4. The surface grafted Co(II) on Ag3PO4 is responsible for the enhancement of photocatalytic activity.

Large-scale fabrication and application of magnetite coated Ag NW-core water-dispersible hybrid nanomaterials

In this work, we report a large scale synthetic procedure that allows attachment of magnetite nanoparticles onto Ag NWs in situ, which was conducted in a triethylene glycol (TREG) solution with iron acetylacetonate and Ag NWs as starting materials. The as-prepared Ag NW/Fe3O4 NP composites are well characterized by SEM, TEM, XRD, XPS, FT-IR, and VSM techniques. It was found that the mass ratio of iron acetylacetonate to Ag NWs plays a crucial role in controlling the amount of magnetite nanoparticles decorated on the Ag NWs. The resulting Ag NW/Fe3O4 NP composites exhibit superparamagnetic properties at room temperature, and can be well dispersed in aqueous and organic solutions, which is greatly beneficial for their application and functionality. Thus, the as-prepared magnetic silver nanowires show good catalytic activity, using the catalytic reduction of methylene blue (MB) as a model reaction. Furthermore, the Ag NW/Fe3O4 NP composites can be functionalized with polydopamine (Pdop), resorcinol-formaldehyde resin (PFR), and SiO2, respectively, in aqueous/ethanol solution. Meanwhile they can also be coated with polyphosphazene (PZS) in organic solution, resulting in a unique nanocable with well-defined core shell structures. Besides, taking Ag NW/Fe3O4@SiO2 as an example, a hollow magnetic silica nanotube can be obtained with the use of Ag NWs as physical templates and a solution of ammonium and H2O2. These can greatly improve the application of the Ag NW/Fe3O4 NP composites. The as-synthesized above nanocomposites have high potential for applications in the fields of polymers, wastewater treatment, sensors, and biomaterials.

B-doped 3C-SiC nanowires with a finned microstructure for efficient visible light-driven photocatalytic hydrogen production

B-doped 3C-SiC nanowires have been synthesized via a facile and simple carbothermal reduction method at 1500 °C for 2 h in a flowing purified argon atmosphere. The obtained nanowires possess a single crystalline and finned microstructure with fins about 100-200 nm in diameter and 10-20 nm in thickness. The diameter of the inner core stem is about 80 nm on average. Due to the smaller band gap, the finned microstructure and the single crystalline nature, the B-doped 3C-SiC nanowires demonstrate efficient activity as high as 108.4 μmol h(-1) g(-1) for H2 production, which is about 20 times higher than that of 3C-SiC nanowhiskers and 2.6 times higher than the highest value reported in the literature for SiC materials.

Silver-loaded nitrogen-doped yolk-shell mesoporous TiO2 hollow microspheres with enhanced visible light photocatalytic activity

Silver-loaded nitrogen-doped yolk-shell mesoporous TiO2 hollow microspheres (Ag-N-TiO2-YSM) were prepared by employing acetic acid as the hollowing controller and triethanolamine as the N source for the first time. Ag nanoparticles (NPs) were uniformly deposited by a simple in situ photo-reduction method, which can prevent the aggregation of Ag NPs. The efficiency of the as-prepared samples was investigated by monitoring the degradation of rhodamine B and ciprofloxacin under visible light irradiation. The experimental results indicate that N-doped yolk-shell mesoporous TiO2 hollow microspheres show higher photocatalytic activity than P25 TiO2 under visible light irradiation because of N doping and the unique yolk-shell structure. In addition, Ag-N-TiO2-YSM shows enhanced activity compared with N-TiO2-YSM due to the SPR absorption of silver NPs and the fast generation, separation and transportation of the photogenerated carriers. Moreover, the Ag contents can affect the photocatalytic activity of the Ag-N-TiO2-YSM composite. A suitable amount of Ag deposition gives the highest photocatalytic activity. A higher loading does not improve the photocatalytic activity of N-TiO2-YSM further. The active species generated in the photocatalytic system were also investigated. Based on our experimental results, a possible photocatalytic mechanism was proposed. The strategy presented here gives a promising route towards the development of delicate metal@hollow semiconductor composites for many applications in photocatalysis.

One-dimension-based spatially ordered architectures for solar energy conversion

The current status, future developments, and challenges of one-dimension-based spatially ordered architectures in solar energy conversion are discussed and elucidated.

Fe2O3–AgBr nonwoven cloth with hierarchical nanostructures as efficient and easily recyclable macroscale photocatalysts

The Fe₂O₃–AgBr nonwoven cloth with hierarchical nanostructures synthesized by an electrospinning–calcination method exhibits efficient photocatalytic activity and easy recycling features.

Fabrication of a heterostructured Ag/AgCl/Bi2MoO6 plasmonic photocatalyst with efficient visible light activity towards dyes

A ternary Ag/AgCl/Bi₂MoO₆ plasmonic photocatalyst was successfully fabricated through a two-step synthesis method.

In situ fabrication of Ag3PO4/TiO2 nanotube heterojunctions with enhanced visible-light photocatalytic activity

Ag₃PO₄/TNT heterojunctions have been fabricated via a facile in situ growth method. Compared with pure Ag₃PO₄, Ag₃PO₄/TNT possesses more active sites, less bulk defects, as well as better dye adsorption properties, and thus exhibits a significantly elevated photocatalytic activity and stability for RhB degradation.

Controlled synthesis of peony-shaped photocatalyst grains of Ag3PO4/Zn3(PO4)2 by coprecipitation and recrystallization technology

Peony-shaped grains of a Ag₃PO₄/Zn₃(PO₄)₂ composite have been synthesized through a coprecipitation and recrystallization technology.