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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]

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]

As a typical wide-band-gap semiconductor, BiPO 4 (BPO) has a great potential for photocatalytical degradation of highly stable benzene (C 6 H 6 ) that has been regarded as a priority hazardous VOC substance in the indoor atmosphere. Hexagonal (H-BPO), monoclinic (M-BPO), and their mixture phase BiPO 4 (M/H-BPO) were selectively synthesized to study the effect of BPO phase structure on the degradation of C 6 H 6 . The samples were characterized by several techniques, including X-ray diffraction, FTIR spectroscopy, UV–vis diffuse reflection spectroscopy, N 2 absorption-desorption measurements, scanning/transmission electron microscopy, and X-ray photoelectron spectroscopy. The results indicated that the monoclinic phase was a thermodynamically stable phase. The band gap energy of H-BPO, M-BPO, and M/H-BPO was 3.74, 3.93 and 3.86 eV, respectively. A transformation from rice-like hexagonal BPO to monoclinic phase nanorods was realized through varying the hydrothermal temperature and the composition of the solvent. The degradation of C 6 H 6 was closely associated with the crystalline phase of BPO and the mineralization rates decreased in order of M– (7.3) > M/H– (1.51) > H-BPO (0.51 μmol·h −1 ·m −2 ). The rates were higher than that of well-known P25 (0.34 μmol·h −1 ·m −2 ). The highest activity of M-BPO could be ascribed to its intrinsic distortion of PO 4 tetrahedron and the largest band gap structure. OH, O 2 − , and photoinduced holes were the major oxidation species accounting for the destruction of C 6 H 6 . [ABSTRACT FROM AUTHOR]

[Display omitted] • Co–CeO 2 was used to activate the PMS for degrading PET plastics. • The degradation rate reached 91.61 % in 6 h after adding 1 mL H 2 O 2 and 5 mM PMS. • Several factors, such as pH and anions, were considered. • SO 4 − played a crucial role in the degradation, compared to OH, O 2 −, and 1O 2. • The possible mechanism of photocatalysis/PMS degradation of PET was proposed. Polyethylene terephthalate (PET) plastic, widely used for packaging owing to its excellent properties, has become a major contributor to plastic waste, for which satisfactory recycling and upgrading treatment technologies are lacking. In this study, Co-doped CeO 2 was used as a photocatalyst to degrade PET plastics in water, and PET degradation was measured according to the weight loss rate. Peroxymonosulfate (PMS) addition to the photocatalytic system enabled the degradation of 53.82 ± 4.48 % of PET plastics, highlighting the excellent PET plastic degradation capability of the photocatalytic PMS system. The study investigated the effects of the catalyst-to-plastic ratio, PMS concentration, initial pH, inorganic anions, humic acid concentration, and hydrogen peroxide (H 2 O 2) addition on the catalytic oxidation system. Contrast experiments revealed that H 2 O 2 addition to the photocatalysis/PMS oxidation system further improved the PET plastic degradation efficiency (91.61 ± 1.50 %). Liquid product analysis, electron paramagnetic resonance, and free radical quenching experiments confirmed that SO 4 − played the most significant role in PET degradation. Finally, a possible mechanism for the degradation of PET plastics in water using the photocatalysis/PMS oxidation system was proposed. [ABSTRACT FROM AUTHOR]