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Ag/Ag 3 PO 4 /active carbon (AC) composite photocatalysts were successfully synthesized using the simple deposition and photoinduced methods. The structures, morphology and photocatalytic properties of as-prepared photocatalysts were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), diffuse reflectance spectroscopy (DRS), photoluminescence (PL) spectroscopy, X-ray photoelectron spectroscopy (XPS). The Ag/Ag 3 PO 4 /AC composite photocatalysts exhibited a conspicuously improved photocatalytic performance for tetracycline (TC) degradation. The optimal conditions of loaded dosage and photoinduced time were investigated, and the results showed that the photoinduced time played an important role in prepared processes, and also that for the loaded dosage of Ag 3 PO 4 . The DRS analysis showed that the composite photocatalysts exhibited strong absorption ability in the visible light range. The radicals trap experiments demonstrated that there were multiple active species during the degrading process of TC. The possible mechanism of improved photocatalytic activity of Ag–Ag 3 PO 4 /AC composite was also proposed. [ABSTRACT FROM AUTHOR]

In the process of treating tetracyclines in wastewater, the influence of the surrounding environment on the efficiency of tetracycline removal plays a vital role. We have successfully prepared Azo@Ag/Ag2O/CN photocatalytic materials that are intelligently responsive to light of different wavelengths via direct precipitation and emulsion polymerization. Tetracyclines are used to simulate pollutants, proving that Azo@Ag/Ag2O/CN achieves intelligent responsiveness under different wavelengths of light. Azo@Ag/Ag2O/CN exhibits conversion from a trans structure to a cis structure when irradiated by UV light, while Vis light irradiation shows the opposite reaction. The photocatalytic degradation rate of the Azo@Ag/Ag2O-10/CN photocatalyst reached 87.7% under Vis light irradiation. Azo@Ag/Ag2O/CN will be converted from a cis structure to a trans structure, and the Ag/Ag2O-10/CN photocatalyst can be released and the contact angle does not change around 130°, showing a state of relaxation. This experiment realized the controllability of the photocatalyst to light. [ABSTRACT FROM AUTHOR]

Photocatalytic mineralization of organic pollutions and simultaneously converting CO2 to CO (tetracycline → CO2 → CO) represents a fascinating way to solve the environmental and energy crisis. This work demonstrates the excellent mineralization and CO2 reduction performance of S-vacancy CdS and reveals the high efficiency of the carbon self-recycling two-in-one photocatalytic system. [ABSTRACT FROM AUTHOR]

In this work, thermo-responsive PNIPAM@AgBr/CSs composite photocatalysts were successfully fabricated by grafting method. The thermo-responsive composite photocatalysts were further characterized by SEM, EDS, XRD, FT-IR, DRS and PL, the results demonstrated that the surface of CSs was successfully loaded with AgBr and further grafted with PNIPAM, and the grafted PNIPAM not only obtained the thermo-responsive performance, but also synergistically enhanced visible light photocatalytic activity toward degradation of tetracycline (TC) antibiotics. The influenced factors of photocatalytic degradation were also investigated, the results showed that the dosage of PNIPAM and the reacted temperature were obviously affected the degradation rate of TC. Lastly, the photocatalytic degradation mechanism of as-obtained thermo-sensitive photocatalyst was also discussed in detail. This work might offer a way to obtain the intelligently composite materials for switchable photocatalytic processes. [ABSTRACT FROM AUTHOR]

High selectivity and fast charge separation are two important factors for photocatalytic wastewater treatment. Herein, we prepared a molecular imprinted Ag/Ag 3 VO 4 /g-C 3 N 4 photocatalyst (MIP) that exhibited great specific recognition ability along with excellent photocatalytic activity. The ultrathin g-C 3 N 4 nanosheets with high surface are used to prepare. The Z-scheme Ag 3 VO 4 /g-C 3 N 4 heterostructure and the surface plasmon resonance of the photoreduced Ag0 together contributed to the improvement of the separation efficiency of photogenerated electrons and holes. In addition, MIP provides the specific recognition ability to preferentially adsorb the target pollutant. The selectivity of photocatalysis was evaluated by the degradation of oxytetracycline and tetracycline solutions. Photoluminescence and transient photocurrent measurements further prove the improved charge separation efficiency of MIP. A plausible photocatalytic reaction mechanism is proposed based on electron spin resonance measurement and the active species trapping experiments, where indicates that the main active species of this photocatalytic process are O 2 − and h+. This research provides an effective strategy for the simultaneous enhancement of selectivity and activity via molecular imprinting. [ABSTRACT FROM AUTHOR]

The interfacial regulation strategy between semiconductors can effectively promote the separation efficiency of photogenerated carriers and enhance photocatalytic activity under the synergistic effect. Herein, AgInS 2 QDs-MoS 2 /GO (AIS-MS/GO) composites were prepared by interfacial coupling of AgInS 2 QDs (AIS), hierarchical MoS 2 and ultrathin GO. Ultrathin GO successfully solved the agglomeration problem of AIS and hierarchical MoS 2. Moreover, the photogenerated carriers were effectively separated and transferred under the synergistic effect of the AIS-MS heterojunction and ultrathin GO, thus promoting tetracycline (TC) degradation and CO 2 reduction performance. The degradation rate of tetracycline (TC) reached 96.5 %, and the yields of CO and CH 4 in the CO 2 reduction products reached 52.6 and 28.5 μmol g–1, respectively, when using the optimized photocatalyst. In-situ FTIR analysis indicated that TC is gradually degraded by small molecules on the composite surface, and has excellent dissociation ability of water molecules during the CO 2 reduction process. This work provides a new vision for the rational design of heterojunction-based photocatalysts using the interfacial regulation strategy for enhancing interfacial charge separation and photocatalytic performance. [Display omitted] • AIS-MS/GO composites were prepared via the interfacial regulation strategy. • The photogenerated carriers were effectively separated and transferred under synergistic and interfacial effects. • The aggregation problem of AIS and hierarchical MoS 2 was effectively solved. • AIS-MS/GO composites achieve a 96.5 % TC degradation rate and 35.1 % selectivity for CH 4. [ABSTRACT FROM AUTHOR]

Graphical abstract Schematic illustration of the formation of CQDs/ZnO@HNTs in the whole synthetic process. Highlights • We have experimentally demonstrated the carbon incorporated ZnO via coupling CQDs. A notable transformation of burger-like CQD s /ZnO morphology was observed and the HNTs have been introduced to improve the dispersity of hybrid photocatalysts. • From efficiently modulation of band structure of CQD s -based materials, the as-prepared CQD s /ZnO@HNTs display a remarkable optical excitation in photogenerated reactive oxygen species (ROS). • This work provides an efficient and novel strategy for element incorporated with introduced inorganic quantum dots owing to the quantum size effect. • It also developed a new sight of CQD s participated phase tuning for semiconductors, offering a beneficial route for expanding the application of VLD photodegradation based on band-tuning semiconductors and other low-dimension materials. Abstract Environmentally friendly photodegradation of refractory pollutants utilizing semiconductor photocatalysis evolution exhibits satisfactory efficiency and low energy consumption, but some of its unbefitting band position largely limits practical applications. The controllable band structure tuning via coupling low-dimensional materials with enormous potential in semiconductor photocatalysis, notably attractive carbon quantum dots (CQDs) induced for a better utilization of low-energy photoexcitation of promising inherent optical properties and photocatalytic performance on organic pollutant degradation. Here, a CQDs modified ZnO hybrid materials was synthesized and the CQDs preluded carbon-incorporated burger-like ZnO nanoparticles clusters were presented thus demonstrated a specific doping-effect. The dispersity improved by loading halloysite nanotube (HNTs) for efficiently photocatalytic activity enhancement. Furthermore, the band structure, excitation and photocatalytic reactive oxygen species (ROS) generation were detected to reveal the photochemical properties and plausible mechanism of CQDs hybrid nanomaterials system. It is observed that the superoxide radical (O 2 −), and singlet oxygen(1O 2) are the principal ROS agents under UV–vis excitations. This work not only displays a CQDs modified system of expanding photo-response range to visible light but also throws a way for quantum elemental incorporated on the influence of band-tuning for semiconductor- dominated photocatalysts. [ABSTRACT FROM AUTHOR]

A series of hamburger-like Ag@ZnO/C core–shell plasmonic photocatalysts have been synthesized via a simple solvothermal method for degradation of tetracycline (TC) under visible light irradiation, possessing high photocatalytic activity and good stability. The presence of localized surface plasmon resonance (LSPR) in the Ag core has increased the photocatalytic activity over an extended wavelength range. The plasmon-induced resonant energy transfer (PIRET) and direct electron transfer (DET) have facilitated the excitation and separation of photogenerated e−/h+ pairs, which has been further confirmed by electrochemical investigations. The presences of hydroxyl radicals (⋅OH), superoxide radicals (⋅O2−) and singlet oxygen (1O2) in the photocatalytic reaction system of Ag@ZnO/C photocatalyst have been demonstrated by electron spin resonance (ESR) measurements. All of the experiment results indicate that the ternary structure of Ag@ZnO/C can effectively enhance the photocatalytic activity. Furthermore, the effects of introduced Ag contents and carbon source dosage were researched by comparative photocatalytic experiments, and the potential structures of photodegradation products were studied by HPLC-MS. A series of hamburger-like Ag@ZnO/C plasmonic photocatalysts was synthesized. The photocatalysts exhibited great photocatalytic activity and stability, and the PIRET and DET have facilitated the excitation and separation of charges. The possible photodegradation mechanism was systematically presented and the potential structure of new photodegradation products was studied. [ABSTRACT FROM AUTHOR]

A series of nebula-like ZnO/CeO 2 @HNTs heterostructure photocatalysts were synthesized via a novel one-step wet-calcination method for degradation of tetracycline (TC) under simulated solar irradiation. TEM, HRTEM, XRD, FT-IR, XPS, DRS, PL, PC, EIS and ESR techniques were applied for characterization of samples. And the potential structure of new photodegradation products was studied by HPLC–MS analysis. The characterization results revealed the enhanced photocatalytic activity of ZnO/CeO 2 @HNTs heterostructure photocatalysts due to the delayed recombination of photogenerated electron-hole pairs. Moreover, surface oxidation state analysis demonstrates that Ce 3+ and Ce 4+ states coexist in CeO 2 , which enhance the separation of electron-hole pairs though cerium oxide shifting between CeO 2 and Ce 2 O 3 under photocatalytic process. In addition, the effects of the calcinating temperature, the molar ratio of ZnO to CeO 2 and the dosage of HNTs on photocatalytic activity of ZnO/CeO 2 @HNTs heterostructure photocatalysts were researched and the best possible values have been found. Furthermore, the photodegradation mechanism was systematically investigated by active species trapping experiment. It revealed that OH radicals play a little role while hole and O 2 − are the more major reactive species in the photodegradation process. [ABSTRACT FROM AUTHOR]