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The H2O activation provides protons without the formation of strong oxidative radicals and can achieve the selective photoreduction of CO2 to CH3OH.

As a kind of rare materials, nano-silver has broad application prospects in the fields of catalysis, medical treatment, new energy and so on. However, there are few reports on the systematic research of nano-silver in ceramic glazes. In this work, different color ceramic glazes were produced by tuning the nano-silver content and optimizing the firing process. The crystalline phase composition, micro-morphology and elemental distribution of fired glazes were analyzed and discussed in depth. The elemental composition and distribution of the samples were studied. The surface of the glazes with varying Ag contents fired under the reducing atmosphere exhibited blue-white. And the blue color is attributable to Rayleigh scattering that may arise because the phase-separation structures existed in glazes. Interestingly, the color of the ceramic glazes with varying Ag contents changed to golden-yellow when the ceramic glazes were fired under the air atmosphere. Golden-yellow color of the samples fired under the air atmosphere is mainly attributable to the silver nano-particles, though Ag+ may be existed in the glazes.

In this work, we present an in situ method to probe the evolution of photoelectrochemically driven surface oxidation on photoanodes during active operation in aqueous solutions. A standard solution of K4Fe(CN)6-KPi was utilized to benchmark the photocurrent and assess progressive surface oxidation on Ta3N5 in various oxidizing solutions. In this manner, a proportional increase in the surface oxygen concentration was detected with respect to oxidation time and further correlated with a continuous decline in the photocurrent. To discern how surface oxidation alters the photocurrent, we experimentally and theoretically explored its impact on the surface carrier recombination and the interfacial hole transfer rates. Our results indicate that the sluggish photocurrent demonstrated by oxidized Ta3N5 arises because of changes in both rates. In particular, the results suggest that the N-O replacement present on the Ta3N5 surface primarily increases the carrier recombination rate near the surface and to a lesser degree reduces the interfacial hole transfer rate. More generally, this methodology is expected to further our understanding of surface oxidation atop other nonoxide semiconductor photoelectrodes and its impact on their operation.

Exploring the environmentally friendly and low-cost synthesis strategies of phthalocyanine (Pc) crystals in just one step is an absolute challenge. The solvothermal synthesis of phthalocyanine crystals shows the advantages of high-quality crystalline products, facile reaction and purification, and low cost. Nevertheless, only a few metal phthalocyanine crystals have been successfully synthesized via solvothermal reactions. In this study, we found that the crystalline β metal-free phthalocyanine needles could be directly prepared via the tetrapolymerization of phthalodinitrile catalyzed by DBU in solvothermal reactions. Similar to the preparation of β-phthalocyanine crystals, the α metal-free phthalocyanine crystals with the specific multiply-laminated structures can be obtained through solvothermal reactions assisted by DBN. SEM characterization showed that the individual β metal-free phthalocyanine has a well-defined quadrangular shape with smooth faces. However, the α metal-free phthalocyanine exhibits a distinctive undulating surface morphology. Both phthalocyanines showed satisfactory thermal stability (from room temperature to about 300 °C), excellent resistance to acid/alkali solution, and fast photoelectric response properties (order of magnitude of response time, 10−6 s) as tested by TG-DSC and TPV, respectively. It is noted that ethanol was used as the reaction medium and the resulting phthalocyanine crystals can be facilely purified using hot ethanol to dissolve the impurities adsorbed on the surfaces of phthalocyanine crystals. Compared to the traditional methods, no re-crystallization operation was carried out for our method. To the best of our knowledge, this is the first report on the solvothermal synthesis of metal-free phthalocyanine crystals with controllable crystal form adjusted by DBU/DBN in one step.

In this work, heterostructured Au@PbTiO3 nanoplates were synthesized successfully via a simple hydrothermal process. It is revealed that Au islands with the size of 8–20 nm selectively deposited on the positively polarized surface of the single-crystal and single-domain PbTiO3 nonaplates. The composite demonstrates an efficient photocatalytic performance toward degradation of Rhodamine B (RhB) solution under UV light. The possible mechanism is that the ferroelectric polarization efficiently separates the photogenerated electrons and holes and reduces the recombination of them. Then, the ferroelectric polarization field urged the electrons concentrated on the positively polarized surface and then transformed oxygen into superoxide radicals to enhance the photocatalytic activity. Recycled activity tests show that the heterostructured Au@PbTiO3 nanoplates would inhibit the photocorrosion behavior and provide high stability.

Electrons can degrade pentachlorphenate sodium (PCPNa) directly or activate molecular oxygen to produce·O2-and ·OH for its degradation. However, less work has been performed to control such two kinds of reaction pathway by modifying BiOCl. Herein, we firstly regulated the reaction pathway between electrons and PCPNa by adjusting the amount of surface oxygen vacancies (OVs) and surface adsorbed hydroxyl groups in I

In this work, we present an in situ method to probe the evolution of photoelectrochemically driven surface oxidation on photoanodes during active operation in aqueous solutions. A standard solution of K

Cobalt species as active sites for photocatalytic reduction of CO2 to valuable products such as methanol have received increasing attention, however, it remains a huge challenge to achieve the high activity. Herein, a pyrolysis-induced-vaporization strategy was successfully employed to fabricate Co/g-C3N4 single-atom catalysts (Co/g-C3N4 SACs) with surface Co atom loading up to 24.6 wt%. Systematic investigation of Co/g-C3N4 SACs formation process disclosed that concentrated-H2SO4 exfoliation of g-C3N4 nanosheets (g-C3N4 NSs) as the substrate followed by a two-step calcination process is essential to achieve ultrahigh metal loading. It was found that the ultrahigh-density of Co single-atom sites were anchored on the g-C3N4 substrate surface and coordinated with two nitrogen and one carbon atoms (Co-N2C). These single dispersed Co-N2C sites on the g-C3N4 surface were found to act not only as electron gathering centers but also as the sites of CO2 adsorption and activation, subsequently, boosting the photocatalytic methanol generation during light irradiation. As a result, the methanol formation rate at 4 h (941.9 μmol g−1) over Co/g-C3N4-0.2 SAC with 24.6 wt% surface Co loading was 13.4 and 2.2 times higher than those of g-C3N4 (17.7 μmol g−1) and aggregated CoOx/g-C3N4-0.2 (423.9 μmol g−1), respectively. Simultaneously, H2 (18.9 μmol g−1 h−1), CO (2.9 μmol g−1 h−1), CH4 (3.4 μmol g−1 h−1), C2H4 (1.1 μmol g−1 h−1), C3H6 (1.4 μmol g−1 h−1), and CH3OCH3 (3.3 μmol g−1 h−1) products were detected over Co/g-C3N4-0.2 SAC. Besides, the photocatalytic activity of the Co/g-C3N4-0.2 SAC for the reduction of CO2 to methanol was stable within 12-cycle experiments (~48 h). This work paves a strategy to boost the photoreduction CO2 activity via loading ultrahigh surface density single atomically dispersed cobalt active sites.

Hydrogen is regarded as a highly efficient and clean renewable energy source. However, the high cost of preferred platinum catalysts becomes an economic burden for its commercial applications. Therefore, the development of cost-effective and robust catalysts, having superior catalytic activity toward hydrogen evolution reaction (HER), is a prerequisite to realize large-scale hydrogen production. We present here a simple electrodeposition strategy of building nickel based alloy catalysts (NiM, M = Co, Cu, Mo, Au, Pt) on titanium (Ti) foils, which are subsequently utilized for catalyzing HER by seawater splitting. The preliminary results demonstrate that the Ti/NiCo and Ti/NiCo electrodes have superior catalytic activity for HER in seawater. All the Ti/NiM electrodes show relatively good long-term stability at −1.0 V vs. RHE over 10 h. The high efficiency and reasonable stability of the alloy catalysts demonstrate promising applications in the rising hydrogen revolution.

Electrons can degrade pentachlorphenate sodium (PCPNa) directly or activate molecular oxygen to produce·O2-and ·OH for its degradation. However, less work has been performed to control such two kinds of reaction pathway by modifying BiOCl. Herein, we firstly regulated the reaction pathway between electrons and PCPNa by adjusting the amount of surface oxygen vacancies (OVs) and surface adsorbed hydroxyl groups in I-doped BiOCl exposed with different facets. OVs on (001) facets-exposed I-doped BiOCl enabled large amount of PCPNa to adsorb on its surface and facilitated the direct reaction between electrons and PCPNa. In contrary, more surface adsorbed hydroxyl groups and oxygen on (010) facets-exposed I-doped BiOCl can retard the direct reaction between electrons and PCPNa via lowering the adsorption of PCPNa and increasing the activation of molecular oxygen by electrons. Although more·O2-and ·OH generated in I-doped (010)-facets exposed BiOCl, I-doped (001)-facets exposed BiOCl exhibited better photocatalytic activity. We proposed that the direct reaction between electrons and PCPNa can enhance the utilization efficiency of photogenerated electrons and improve photocatalytic degradation efficiency of PCPNa.

Without sacrifice of photovoltaic performances, low-platinum alloy counter electrodes (CEs) are promising in bringing down the fabrication cost of dye-sensitized solar cells (DSSCs). We present here the realization of ZnO nanostructure assisted hollow platinum-nickel (PtNi) alloy microstructure CEs with a simple hydrothermal methods and maximization of electrocatalytic behaviors by tuning Zn precursors. The maximal power conversion efficiency is up to 8.74% for the liquid-junction dye-sensitized solar cells with alloyed PtNi0.41 electrode, yielding a 37.6% cell efficiency enhancement in comparison with pristine solar cell from planar Pt electrode. Moreover, the dissolution-resistant and charge-transfer abilities toward I−/I3− redox electrolyte have also been markedly enhanced due to competitive dissolution reactions and alloying effects.

Nano sized copper oxide was firstly employed for producing Jun-red glazes. A series of Jun-red glazes were prepared by adjusting the copper oxide nanoparticle content and the valance state of elemental copper in the glaze matrix. The coloring and microstructure of each glaze was investigated by spectrophotometer, XRD, SEM, XPS and TEM. Under reducing conditions, the red glaze color gradually darkens with increasing CuO content from 0.5 to 1.0 wt %. Interestingly, the coloring of the samples fired under reducing atmosphere turned to be green-blue, when the content of nanosized CuO was increased to 1.5 wt %. We also found that increased CuO content increases the size of phase separation in the glazes. As comparison, the coloring of samples fired without nanosized CuO are slightly blue under reducing atmosphere, which is attributed to the structural color generated owing to the Rayleigh scattering. Red color of the Jun glazes may arise from elemental copper nanoparticles. The current research utilizing modern nanotechnology provides a new insight into both the “furnace transmutation” and “color regulating” of the ancient Jun-red glazes. This article is protected by copyright. All rights reserved.

By using a novel Zn(S) 2 L complex (L = N–hexyl–3–{2–(4–(2,2′:6′,2′′–terpyridin–4′–yl)phenyl)ethenyl}carbazole) as a surface stabilizing agent, the self–assembled microspheres of Zn(S) 2 L–capped ZnS nanocrystals are obtained in a simple ethanol solvothermal process. Because of the strong π character of the two terminal sulfur atoms (S 1– valence state) in the Zn(S) 2 L complex, the Zn(S) 2 L complex could incorporate ZnS nanocrystals together by a homologous Zn⟵S→Zn unit interface. In the work, the homologous Zn⟵S→Zn unit interface is proposed to function as a π–conjugated bridge for effective electron–transfer transition from Zn(S) 2 L moiety to ZnS nanocrystal to significantly improve the photoelectric response performance, such as the long lifetime of photogenerated charge carriers from 8 × 10 −8 s to 4 × 10 −5 s and the high recombination luminescence quantum efficiency (QE) up to 69%, which are confirmed by the systematically investigation with Raman spectra, XPS spectra, Uv–vis absorption spectra, photoluminescence (PL) spectra and transient photovoltage (TPV) technique. The ZnS/Zn(S) 2 L used as extra electron donor in organic/inorganic hybrid solar cell device could increase performance up to about 30%.

Fe3O4@SiO2-SO3H nanocomposites were successfully synthesised as the efficient magnetically separable solid acid catalysts for an esterification reaction. The resultant catalysts were characterised by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, Fourier-transform infrared spectroscopy, vibrating sample magnetometer (VSM), and nitrogen physical adsorption analyses [Brunauer–Emmett–Teller (BET) theory]. The catalytic activities of as-prepared Fe3O4@SiO2-SO3H nanocomposites were also investigated for the esterification of n-butyl acetate and isoamyl acetate. The acid esterification rate was confirmed by gas chromatography. The results showed that the Fe3O4@SiO2-SO3H nanocomposites can be as candidate cataysts for the concentrated H2SO4 for the esterification reaction of n-butyl alcohol or isoamyl alcohol. More importantly, the magnetic catalysts can be easily separated from the reaction system by a magnetic bar and reused at least three recycles without significant degradation of their activities.

To explore the simple, facile, environmental friendly and low cost catalytic technique to decolorize harmful dye contaminants in solution and understand the mechanism is an interesting and practical research. In this paper, we provide a highly efficient and convenient method for fast decolorization of dyes (methylene blue and rhodamine B) in aqueous solution catalyzed by iron octacarboxyphthalocyanine (FeOCPc) or cobalt octacarboxyphthalocyanine (CoOCPc). Compared to the traditional methods, our method is very simple. The 30 mg/L methylene blue could be decolorized almost absolutely less than 30 min just by dispersing FeOCPc powders into the dye solution. The decolorization of rhodamine B at high concentration (30 mg/L) could be achieved to 100% decolorization degree less than 20 min in the presence of FeOCPc and tert-butyl hydroperoxide (BuOOH). Moreover, the ESR and HPLC-MS measurement were performed to determine the active radicals and various intermediates in decolorization processes and the possible catalytic mechanism was proposed. It is noted that both FeOCPc and CoOCPc catalysts show the different catalytic oxidation behaviors depending on the oxidant (O2 or BuOOH). Our investigation provides a novel, low cost and convenient strategy to purify the environmental pollutions.

To remove the harmful dye contaminants via an efficient, facile and low energy consumption route is a grave challenge in current chemical industry. Though the great progresses of TiO2 photocatalysis and enzymatic degradation have been witnessed, the strategy for satisfying the above requirements is still worth exploring. Herein, we develop a biomimetic catalysis strategy for the fast decolorization of organic dyes catalyzed by iron octacarboxylic phthalocyanine (FeOCPc) complexes assisted with tert-butyl hydroperoxide (BuOOH). Methyl orange (MO) and methylene blue (MB) were used as the model pollutants and experimental results show that the decolorization degree of 25 mg/L MO could achieve 100% within 20 min and 80% for 25 mg/L MB within 30 min. The molar ratio for FeOCPc/MO and FeOCPc/MB is 0.146 and 0.142, respectively. Interestingly, other than the high-valent iron-oxygen active species, tert-butyl peroxyl radicals and hydroxyl radicals were detected as the active species generated during the catalytic oxidation by the electron paramagnetic resonance (EPR) measurement. This work not only provides a distinctive biomimetic catalysis system of FeOCPc–BuOOH for the fast bleaching of dye pollutants, but also proposes the new insight on a mechanism based on the cooperation catalysis of iron-oxygen active species, tert-butyl peroxyl radicals and hydroxyl radicals.

(Photo)electrochemistry enables the synthesis of high-value fine chemicals and highly selective activation of molecules that are difficult to prepare using conventional chemical methods. In this work, light-driven NADH (reduced nicotinamide adenine dinucleotide) regeneration is achieved using a molecular Rh(III) mediator on Si photoelectrodes. This process is observed to be highly sensitive to the surface nature of Si photoelectrodes, exhibiting an overpotential reduction up to 600 mV on Si nanowires (SiNWs) as compared to planar Si. The use of a molecular mediator and SiNWs enables 100% selectivity toward NADH synthesis within a broad potential window. The origin of the striking difference is identified as the multifaceted nature of SiNWs.

To acquire a well bonded interface between the copper and the diamond particles in diamond-copper matrix composites, an available process to apply a vapor deposited aluminum (Al) coating onto diamond particles was used to solve this interfacial problem. The diamond-copper matrix composites were prepared by spark plasma sintering (SPS) process and the effect of Al-coated diamond particles was demonstrated. The experimental results showed that the densification, interfacial bonding and thermal conductivity of Al-coated composites were evidently improved compared to those of the uncoated composites. A maximum thermal conductivity (TC) of 565 W/(m·K) was obtained in the coated composite containing 50vol% diamond particles sintered at 1 163 K. Additionally, the experimental data of thermal conductivity and coefficient of thermal expansion (CTE) were compared with the predictions from several theoretical models.

This is the first time a series of chemically homogeneous superlattice Cu7.2Sx (x = 4.07, 4.52, 6.01, 6.20, 6.45) nanowires have been successfully synthesized by heavy doping of S2 species in Cu7.2S4 lattice through a simple wet-chemical route. This superlattice structure is a polytypoid structure tuned by adjusting the atom ratio of S2 to S in lattice configuration. The perfect superlattice Cu7.2S6.20 structure interestingly consists of two alternating lattice fringes corresponding to the atom layers of Cu–S and Cu–S2 in an even spacing of 5.70 A. The article describes the formation, morphology, composition and structure of the Cu7.2Sx superlattice nanowires. Photoluminescence (PL) spectra and transient photovoltage (TPV) measurements reveal that the generation and separation efficiency of the photogenerated charges of Cu7.2Sx nanowires could be greatly improved by adjusting the S2/S ratio in the lattice configuration, and thus enhance the luminescence quantum efficiency. This study reveals that the S2 species in Cu7.2Sx nanowires play a very important role in determining the dynamic properties of photogenerated charge carriers.

Chromogenic reaction catalyzed by metal phthalocyanine (MPc) complexes is a novel and practical method for the facile identification of phenolic pollutants. Exploring the catalytic reaction mechanism is the current concern in the investigation. In this work, tetranitro iron (II) phthalocyanine (TNFe(II)Pc) and iron (II) phthalocyanine (Fe(II)Pc) catalyzed chromogenic reactions were studied at the B3LYP level on the basis of the density functional theory (DFT) calculation. The molecular structure, atomic charge, and frontier molecular orbital of these two kinds of iron phthalocyanine complex were investigated. The calculation results demonstrate that no obvious difference for geometry structures of Fe(II)Pc and TNFe(II)Pc macrocycle can be found, while the atomic charge of Fe atom increases obviously with the four nitro groups substituted on the peripheral of macrocycle. By applying the descriptor of donor–acceptor molecular hardness, the difference of electron transfer from chlorophenol substrates to TNFe(II)Pc/Fe(II)Pc was well explained. Our investigations could provide a new strategy in designing various MPc catalysts for chromogenic identification of chlorophenol pollutants.

The phase and morphology evolution in the Bi–W–Cl–O solvothermal system was investigated. The products were characterised by X-ray diffraction, SEM and high resolution TEM. The optical properties and photocatalytic performance of the samples were evaluated. The results show that the composite Bi2WO6/BiOCl sample was obtained for the reaction time of 15 h. The light absorption ability and the photodegradation efficiency were enhanced obviously for Bi2WO6/BiOCl. The mechanisms for the formation of the composite and the optimisation of the photocatalytic activity were also discussed.

Well-dispersed and uniform ZnSn(OH)6 submicrocubes with the average size of about 400 nm were successfully synthesized through the chemical conversion of different precipitates assisted by ultrasonic treatment and the subsequent aging process in an economical aqueous solution. The products were characterized with X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), Thermogravimetric analysis (TG) and Differential scanning calorimetry (DSC). The growth mechanism has been proposed and the reaction conditions were carefully investigated. It was found experimentally that ultrasound irradiation, aging process and the presence of Na2CO3 in the synthetic process had an impact on the formation of the ZnSn(OH)6 submicrocubes. Additionally, the obtained ZnSn(OH)6 submicrocubes can be applied for the preparation of the Zn2SnO4/SnO2 mixtures by simple calcination.

An innovative method of in-situ reactive preparation of diamond/silicon(Ti) matrix composites by spark plasma sintering (SPS) process was applied to produce specimens and the effect of Ti-addition to Si matrix was demonstrated. The relative density of diamond/Si(Ti) matrix composite was >98.1% in a volume fraction of diamond ranging from 40% to 60%. Actually, Si(Ti)/diamond composites containing 60% in volume diamond particles yielded a thermal conductivity (TC) of 525 W m−1 K−1 at room temperature along with a thermal expansion coefficient (TEC) of 1.643×10−6 K−1 at 573 K. TC and TEC of the experimental data were compared with the predictions from several theoretical models. Microstructures of these materials were studied by field emission scanning electron microscopy (FE-SEM) and X-ray diffraction (XRD). Ti addition lowered the melting point and resulted in the formation of TiSi2 phase in Si matrix. The results show that Ti addition is an effective approach for promoting the relative packing density and improving thermal conductivity of sintered samples.

A novel thermo- and biodegradable MnSt2–kaolin–polyethylene (signed as MKPE) composite film was prepared through a melt blending technique. Manganese stearate and common kaolin were employed as thermo-degradable additives and biodegradable promoter to improve the degradable efficiency of the waste PE. Thermo-oxidative testing was carried out in an air oven maintained at 70°C simulating a compost temperature. The biodegradation of the aging films was also investigated by analysis of evolved carbon dioxide of films in aquatic test systems according to the International Standards ISO 14852 (1999). The composite film was characterized by electronic universal testing machine, scanning electron microscopy, energy-dispersive X-ray spectroscopy, attenuated total reflection-flourier transformed infrared spectroscopy and thermo gravimetric analysis. These results showed that the MKPE film exhibited a high degree of susceptibility to thermo-oxidation and biodegradation. After thermal aging for 30 days, the mechanical properties of MKPE films reduced quickly and oxygen groups were introduced into the polymer chains. The kaolin particles wrapped in polymers were exposed gradually because of the rupture of polymer chains by thermal aging. The biodegradation degree reached 24.26% after incubation in an aqueous medium for 60 days. A possible mechanism for thermal oxidative degradation and biodegradation was also discussed. POLYM. COMPOS., 36:939–945, 2015. © 2014 Society of Plastics Engineers

In this study, we present flower-like rutile TiO 2 superstructures could be successfully fabricated by taking advantage of a facile solution-phase approach at room temperature. The surface area and amount of surface hydroxyl groups on rutile TiO 2 superstructures could be tuned by calcing the sample at different temperatures. Photocatalytic experiments demonstrated the room temperature synthesized rutile TiO 2 superstructures exhibited excellent photocatalytic activity compared to that of the calcined ones, which were thought to be mainly attributed to its large surface area. We further studied the photocatalytic process of RhB on different rutile TiO 2 superstructures by active species trapping experiments and analyzed the relationship between the major active species and the main influencing factors responsible for the photocatalytic performance for elucidating a surface area and surface charge cooperative photocatalytic mechanism.

Ag3PO4/BiOBr composites were prepared by a facile room temperature liquid phase method. The samples were characterised by X-ray diffraction, SEM, energy dispersive X-ray spectroscopy, ultraviolet–visible and photoluminescence (PL) techniques. The photocatalytic activity was evaluated by photodegrading methylene blue under visible light irradiation. The results show that Ag3PO4/BiOBr composites were successfully formed and the Ag3PO4 nanoparticles were randomly distributed on the surface of BiOBr nanosheets. The composites exhibit better visible light absorption ability, and the PL results show that the composites have enhanced photogenerated carrier separation efficiency. The best photocatalytic performance is obtained for the sample with Ag/Bi ratio of 0·5, the photocatalytic efficiency of which is six times that of BiOBr. The improvement of the photocatalytic activity is associated with the coupling effects of the two semiconductors.

Solar water splitting promises a solution to challenges associated with the intermittent nature of solar energy. Of different implementations, photoelectrochemical water splitting, where one or more photoelectrodes harvest light and catalyze water splitting, represents a convenient platform to understand the governing principles of charge behaviors, especially at the light absorber|H2O interface. This Perspective recognizes and discusses the importance of the photoelectrode surface to solar water splitting performance. It presents discussions within the context of a prototypical water splitting material, Ta3N5, which has gained growing attention lately for its outstanding initial performance. Insights into the mechanisms by which Ta3N5 functions are presented, followed by examples of recent efforts to circumvent the issues that Ta3N5 decays rapidly under solar water splitting conditions. Our visions on the future directions of semiconductor-based solar water splitting will be presented at the end.

Ag 3 PO 4 /BiOI composites were successfully prepared by a facial room temperature liquid phase method. Ag 3 PO 4 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 Ag 3 PO 4 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 Ag 3 PO 4 /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.