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The traditional photocatalysts have no selective photocatalysis ability and are difficult to separate and recycle. Herein, the imprinted modified non-metal S-scheme heterojunction photocatalytic membrane (IM-NSH-PM) was prepared via imprinting modification technology and dopamine (DA) tight adhesion method, which possessed high throughput (2548.6 L m−2 h−1 bar−1), good self-cleaning performance, excellent stability and recovery performance. The cross-linking and polymerization of DA on PVDF membrane surface can form a strong interaction between basement membrane and imprinted modified non-metal S-scheme heterojunction (IM-NSH), which made IM-NSH-PM adhered closely together. Besides, the formed S-scheme heterojunction between PDI and g-C 3 N 4 , which weakened the recombination rate of electrons and holes and further improved the photodegradation ability. The photodegradation rate of TC by IM-NSH-PM reached 71.88%. More importantly, under the action of imprinting modification, IM-NSH was endowed with many imprinted cavities consistent with the three-dimensional structure of tetracycline (TC), thereby TC can be preferentially selective adsorbed and degraded, and the selectivity coefficient of IM-NSH-PM to non-imprinted modified non-metal S-scheme heterojunction photocatalytic membrane (NIM-NSH-PM) was 1.88. This work shows a meaningful idea for exploring self-cleaning membranes with good selective photodegradation ability for the target pollutant. [Display omitted] • IM-NSH-PM with good flux, self-cleaning, stability and recovery performance is obtained. • A strong interaction formed between PVDF and IM-NSH makes IM-NSH-PM closely together. • The formed S-scheme heterojunction enhances the degradation ability of pollutants. • The ability of IM-NSH-PM to specifically degrade TC is enhanced by imprinting modification. • The selectivity coefficient of IM-NSH-PM to NIM-NSH-PM can reach 1.88. [ABSTRACT FROM AUTHOR]

[Display omitted] • Z-scheme silver phosphotungstate/polyimide photocatalyst was synthesized. • Self-assembly and in-situ solid-phase thermal polycondensation were utilized. • Keggin units act as the shuttle redox mediators for Z-scheme photocatalytic system. • The target photocatalysts exhibit enhanced visible light photocatalytic activity. • Oil-H 2 O mixed system can enhance the degradation process of AFB1. Silver phosphotungstate/polyimide (MAPI) photocatalyst was successfully synthesized by a multi-step strategy combining the self-assembly and in-situ solid-phase thermal polycondensation. The construction of MAPI photocatalysts and their photocatalytic activity were investigated. The polyimide (PI) in MAPI photocatalysts obtains the weakened π-π stacking structure and more dendritic crystalline structure. However, the POMs-π interactions, charge-transfer form in conjugated organic ligands-modified polyoxometalate (POMs) materials, and the close contact between main components are beneficial to the charge transfer in MAPI photocatalysts. The coordination interactions of Keggin anions and organic ligands allow the Keggin units released during the thermal treatment process to act as shuttle redox mediators for Z-scheme heterojunction photocatalysts. The changes related to the physicochemical and interfacial interactions of the components enable the MAPI photocatalysts to exhibit the enhanced photocatalytic activity. Pristine PI shows little activity for photocatalytic degradation of Aflatoxin B1 (AFB1) under visible light (λ ≥ 420 nm) irradiation, but the rate constant k of 5-MAPI was 7.34 and 4.46 times than that of pristine AgPW and P25, respectively. The presence of H 2 O and the transfer behavior of AFB1 in the oil-H 2 O mixed system significantly promoted the photocatalytic degradation efficiency of AFB1 in peanut oil. Z-scheme charge transfer path and the photocatalytic degradation pathway of AFB1 were also proposed. Combined with the density functional theory (DFT) calculation results, AFB1 will be firstly degraded by the ·OH-induced cycloaddition reaction at the C19 = C20 of furan ring. Subsequently, methoxy (C23-O22), furan ring, lactone ring and carbonyl group (C9 = O10) are degraded in sequence. This work can provide some interesting insights into the construction of polymer/insoluble POMs photocatalysts and the photocatalytic degradation of exogenous harmful substances in vegetable oil. [ABSTRACT FROM AUTHOR]

[Display omitted] • C and F co-doped TiO 2 nanosheets were synthesized by pyrolysis of layered MXene. • C-F-TiO 2 was applied to photocatalytic degradation of 2,4,6-TCP. • The doping of C and F increased the generation of active radicals and decreased the band gap. • The recombination rate of photogenerated electron-hole was inhibited. • C-F-TiO 2 nanosheets exhibited remarkable photocatalytic activity. Nonmetal doping is widely used in the modification of titanium dioxides (TiO 2) for photocatalytic applications. As a typical two-dimensional layered nanomaterial, the excellent physical and chemical properties of MXene materials have been the focus of current research. In this study, carbon and fluorine co-doped MXene derived TiO 2 nanosheets (labelled as C-F-TiO 2) were successfully synthesized and used as catalysts for degrading 2,4,6-trichlorophenol (2,4,6-TCP) under UV light irradiation. The C-F-TiO 2 with ultrathin nanosheet structure enhanced light absorption range and decreased the bandgaps. The degradation efficiency of 2,4,6-TCP by C-F-TiO 2 was over 99 % in 90 min, and the degradation rate was more than twice that of commercial TiO 2. The degradation rate still remained about 90 % in 90 min after five cycles. The results of quenching experiments and electron spin resonance (ESR) illustrated that more reactive oxygen species (ROS) were generated in the C-F-TiO 2 /UV system, which was 1.5 times that of commercial pure TiO 2 , and •O 2 – was the dominant ROS for 2,4,6-TCP degradation. This study provided insight to utilize physicochemical characteristics of MXene to synthesize non-metal co-doped TiO 2 nanosheet as a catalyst, exhibiting excellent reactivity in the potential application for organic pollutant degradation. [ABSTRACT FROM AUTHOR]

Imprinted P25@IL nanoreactor prepared in aqueous-phase via stable interaction forces between IL and LEV exhibited excellent selectivity and photocatalytic ability. [Display omitted] • Imprinted P25@IL nanoreactor is obtained by aqueous-phase microwave polymerization strategy. • The strong interactions between IL and LEV overcome the interference of water molecules. • Type II heterojunction formed between IL and P25 improves the photocatalytic activity. • Imprinted cavity enhances the selective degradation ability. Common molecular imprinted photocatalysts are usually prepared in highly toxic organic solvent medium, which will be disturbed by water molecules and swelling differences when used for selective recognition in the aqueous phase. In this study, an ionic liquid (IL) was used as the functional monomer and functionalized P25@IL heterojunction molecular imprinted photocatalytic nanoreactor, referred to as imprinted P25@IL nanoreactor, were prepared via the aqueous-phase microwave polymerization strategy. Imidazole-based IL cations can provide π electron clouds, and side chains are easily functionalized and modified, resulting in strong interactions such as π-π and ion dipoles being formed between IL and levofloxacin hydrochloride (LEV), which can overcome the interference of water molecules and achieve better selective adsorption and degradation of LEV in aqueous medium. The selectivity coefficient of imprinted P25@IL nanoreactor relative to P25 and functionalized P25@IL heterojunction molecular non-imprinted photocatalyst (non-imprinted P25@IL photocatalyst) were 2.69 and 2.26, respectively. More importantly, with the formation of IL-P25 heterojunction and surface imprinted layer, the photocatalytic performance of imprinted P25@IL nanoreactor was 2.33 times higher than that of P25. Our findings offer a novel approach to the synthesis of water-soluble functional monomers and the aqueous-phase synthesis of molecular imprinted photocatalytic materials. [ABSTRACT FROM AUTHOR]