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The novel photocatalysts of Ag/AgBr/Bi4O5Br2 layered microspheres (AAB‐LMs) were firstly constructed via the in‐situ deposition and visible‐light photoreduction approach. Their compositions, structures, morphologies and optical properties were characterized by various techniques. The photocatalytic efficiencies of AAB‐LMs‐10 were 28 and 3.4 times higher than those of Bi4O5Br2‐LMs towards degrading acid orange II and aniline, respectively. The superior photocatalytic behavior of AAB‐LMs benefited from efficient separation and transfer of photo‐generated charges, which was mainly credited to the surface plasmon resonance effect of Ag nanoparticles and the synthetic interaction among Ag, AgBr and Bi4O5Br2. O2− and h+ were characterized as the predominant photoactive species in this AAB‐LMs‐photocatalysis system. Moreover, due to the presence of radical species Br0, which was verified by the detection of bromoaniline and dibromoaniline during the photocatalytic degradation process of aniline, Z‐scheme mechanism rather than the conventional heterojunction mode was more suitable to explain the enhanced photocatalytic performance of AAB‐LMs. [ABSTRACT FROM AUTHOR]

In this study, an electromagnetic induction electrodeless lamp (EIEL) was first introduced into UV advanced oxidation processes (AOPs) for photodegradation of Diatrizoate (DTZ), which was the most persistent iodinated X-ray contrast medium (ICM), and traditional Hg lamps were taken as references. Direct photolysis rate of DTZ under EIEL irradiation was 1.34 times as that under Hg irradiation, but the electric energy consumption was 0.87 times. In this sense, the combination of EIEL and oxidants (O 2 , H 2 O 2 and S 2 O 8 2− (PS)) was further investigated. The remarkably increased photodegradation rates were observed in UV/PS system due to primary contribution rate of SO 4 − (62.5%) based on the results of radical concentrations and second-order rate constants of DTZ with SO 4 − and OH. Inorganic ions influencing the photodegradation process were investigated. The effect of natural organic materials (NOMs) in UV/PS system was studied based on contribution ratios of light screening effect and quenching. Transformation mechanisms of DTZ in UV/PS system included deiodination, intramolecular cyclization, decarboxylation, deacetylation and deamination, which were further confirmed by frontier electron density calculations. The study indicated that UV/PS with EIEL irradiation has the potential to remove pharmaceuticals in contaminated aquatic environments. [ABSTRACT FROM AUTHOR]

Capacitive deionization (CDI) is a new technology for the desalination of brackish water and its performance is greatly affected by the electrode materials utilized. Biomass-derived carbons have attracted significant attention as CDI materials due to their high availability, inexpensiveness, renewability and eco-friendly characteristics. In this work, Platanus acerifolia (Aiton) Willd. fruit-derived nitrogen-doped porous carbon (sf-APAWx) is prepared through carbonization at 450 °C, followed by NaOH activation at different temperatures of 700, 800 and 900 °C. The sf-CPAW activated at 800 °C possesses a large specific surface area (3846 m2 g−1), affluent pores and a hierarchical structure; and exhibits a high specific capacitance of 138.81 F g−1, a satisfactory salt adsorption capacity of 18.05 mg g−1 and the fastest salt adsorption rate of 1.01 mg g−1 min−1. These results demonstrate the potential of sf-APAW800 as an electrode material for CDI and the sustainable use of abandoned resources. [Display omitted] • Hierarchical structure of sf-APAW800 was synthesized through NaOH etching reaction. • Activation temperature has an important impact on the properties of the materials. • sf-APAW800 achieves SAC of 18.05 mg g−1 and a SAR of 1.01 mg g−1 min−1. • sf-APAW800 is a promising and economical CDI electrode for capacitive deionization. [ABSTRACT FROM AUTHOR]

Carbon nitride is one of the most promising metal-free photocatalysts to harvest solar light for energy conversion and pollutant treatment. Unfortunately, its photocatalytic performance is impeded by the sluggish charge carriers due to the high symmetry of unit cells of chemical structure. Fabrication of an internal electric field (IEF) in carbon nitride-based photocatalysts is evidenced to be a productive strategy to actuate the fast separation of photo-excited charge carriers and navigate their migrations to active sites for high apparent quantum efficiency (AQE) and throughputs. In the current work, a comprehensive review of IEF in different types of carbon nitride-based heterojunctions will be well presented. Emphasis will be put on the latest progress of IEF generation by hosting 2-dimensional (2D) carbon nitride nanosheets with different dimensional materials, IEF modulation by interfacial engineering as well as IEF identification and monitoring. Relationships between IEF and photocatalytic performances in various processes will also be enlightened. Finally, this review will suggest the challenges and future perspectives of IEF-driven photocatalysis. This review brings the intrinsic impetus of charge carriers in a photocatalyst to the forefront and is anticipated to provide guidance to configure powered IEF in 2D carbon nitride-based heterostructures toward efficient energy conversion and environmental purification. [Display omitted] • Internal electric field (IEF) in carbon nitride-based heterojunctions is reviewed. • IEF generation, modulation identification and monitoring are emphatically discussed. • Relationships between IEF and photocatalytic performances are enlightened. • The challenges and perspectives of IEF-driven photocatalysis are suggested. [ABSTRACT FROM AUTHOR]

The occurrence of nitrated polycyclic aromatic hydrocarbons (NPAHs) in sediments has been widely reported, but research on NPAH bioavailability is lacking. In this study, a self-made zeolite imidazolate framework-8/hexagonal boron nitride (ZIF-8/h-BN) solid-phase microextraction (SPME) fiber and commercial Tenax are compared as efficient tools to predict the bioavailability of NPAHs in sediments with bioassays using Cipangopaludina chinensis. During the process of SPME, the NPAH concentrations on the ZIF-8/h-BN fibers reached extraction equilibrium after 72 h. The fiber extraction of NPAHs in sediments was well-fitted by the pseudo first-order kinetic model with a rate constant of 2 × 10−2 h−1 (R2 > 0.98). The extraction rates ranking of NPAHs in sediments was 2-nitrobiphenyl>1-nitropyrene>5-nitroacenaphthene>2-nitrofluorene. Compared with SPME, NPAH concentrations reached equilibrium after 168 h for the Tenax extraction. The orders of magnitude of fast, slow, and very slow desorption rate constants were 10−1, 10−2, and 10−4, respectively. At extraction equilibrium (168 h), the SPME was close to the bioavailability of the NPAHs in sediments to Cipangopaludina chinensis with a slope statistically approximated to one. In addition, the linear regression for SPME (R2 = 0.7285) was slightly higher than that of the Tenax extraction (R2 = 0.7168) over a short time (6 h). This could be because the coating material of ZIF-8/h-BN can rapidly adsorb freely dissolved NPAHs, and the SPME fibers can accurately predict the bioaccumulated concentrations of NPAHs in exposed organisms by measuring the concentration of NPAHs in the pore water of sediment. This study provides a time-saving and easy procedure to predict the bioavailability of NPAHs in sediments. [Display omitted] • A novel SPME fiber ZIF-8/h-BN was first used to predict NPAHs bioavailability. • ZIF-8/h-BN fiber rapidly reached extraction equilibrium. • ZIF-8/h-BN fiber can be easily separated from sediment. • SPME provided a reliable prediction result with bioaccumulation. [ABSTRACT FROM AUTHOR]

A series of Ag3PO4/BiOCOOH composite photocatalysts have been successfully synthesized by a simple in situ ion precipitation method. The crystallinity, morphology, microstructure, composition and optical property were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM), energy dispersive spectrum (EDS), Fourier transform infrared spectrometer (FT-IR), X-ray photoelectron spectroscopy (XPS), UV-Vis diffuse reflectance spectrophotometer (DRS). The as-prepared catalysts exhibited excellent photocatalytic activity for the degradation of RhB and MB under visible light irradiation, the 2:1 Ag3PO4/BiOCOOH exhibited the best photocatalytic activity. By adding different free radical scavengers, the catalytic mechanism was discussed. In the process of degradation of RhB, holes (h is the main active species, O played a certain active role, OH played a small role. In the process of degradation MB, holes (h is the main active species too, O also played a certain active role, OH almost does not work. Ag3PO4/BiOCOOH composite photocatalysts with different molar ratio have been successfully synthesized via a simple in situ ion precipitation method. The formed heterostructure between BiOCOOH and Ag3PO4 can improve the separation efficiency of photo-induced electrons and holes. The as-prepared Ag3PO4/BiOCOOH composites exhibited excellent photocatalytic activity in the degradation of RhB and MB under visible-light illumination. [ABSTRACT FROM AUTHOR]