查找使用阿拉丁产品的科研文献

Regenerative treatment of aquatic pollutants of microplastic and antibiotics based on synergistic effect of magnetic biochar/protonated g-C3N4

Zifeng Li,Rui Shan,Guoqiang Wei,Leyi Huang,Dong Liang,Haoran Yuan,Yong Chen

Microplastics as emerging contaminants can easily form composite pollutants with other organic substances like antibiotics with higher environmental risks, posing a significant threat to aquatic ecosystems. Herein, a composite was prepared though electrostatic self-assembly of magnetic biochar and protonated g-C 3 N 4 for the simultaneous removal of microplastics and antibiotics. This composite serves as a dual-function material, leveraging its porous structure and functional groups to promote both photocatalytic degradation of antibiotics and effective adsorption of microplastics, which exhibited an adsorption capacity of PS microplastic of 56.90 mg/g and achieving stable removal of TC (30 mg/L) under irradiation of 2 h over multiple cycles with minimal efficiency loss. Magnetic biochar component not only critically enhances photocatalytic degradation efficiency of antibiotic by enriching pollutants and promoting charge separation, but also enables convenient separation and allows for excellent reusability. Moreover, sequential dissolution and electrospinning strategy not only facilitates adsorbent regeneration but also achieves the upcycling of microplastics into a high-value-added plastic film. Additionally, regenerated composite also exhibited excellent performance of PS microplastic removal with low adsorption activity decay over four cycles. This synergistic adsorption-photocatalysis system provides an effective and practical strategy for purifying water contaminated with complex emerging pollutants, offering a valuable reference for development of integrated environmental remediation technologies.

One Step Synthesis of ZnO/g-C3N4 Composite for Photocatalytic Degradation of Methylene Blue and Emerging Contaminants Under Sunlight

Zhangxu Chen,Fanli Meng,Hongyun Ren,Lifen Zhang,Minglian Fu,Danchen Zhu

A key factor limiting the photocatalytic performance of pure graphitic carbon nitride (g-C 3 N 4 ) is the swift recombination of photogenerated electron–hole pairs. To address this issue, the ZnO/g-C 3 N 4 composites were synthesized via a one-step calcination method. Their structure, composition, and morphology being characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and scanning electron microscopy (SEM). An L 16 (4 5 ) orthogonal array was employed to investigate the effects of various factors on the removal efficiency. The results exhibit that under optimal conditions (sunlight irradiation time: 20.0 h, pH: 7.00, catalyst dosage: 40 mg, ZnO/g-C 3 N 4 mass ratio: 4:1), the methylene blue removal rate reached 92.36%. Comparative experiments demonstrated removal efficiencies of 43.64% for phenol, 52.13% for tetracycline, and 40.26% for pyridine, respectively. Moreover, the removal rate of methylene blue can still reach 90.12% after five cycles. Trapping experiments for active species confirmed that photogenerated electrons and holes are critical for methylene blue degradation. ZnO doping g-C 3 N 4 improves the methylene blue removal performance of g-C 3 N 4 , providing a facile strategy for developing g-C 3 N 4 /metal oxide heterostructure to deal with emerging contaminants in the future.

A colorimetric DNA chimera biosensor based on bivalent split aptamers and G-quadruplex DNAzyme to detect norfloxacin in seafood

Wen Zhu,Xinya Mo,Hong Chen,Yuyang Zhang,Jianan Sun,Jiao Li,Sai Wang,Xiangzhao Mao

Norfloxacin (NOR) residue in animal-derived food poses a significant concern due to its role in fostering bacterial resistance and potential human health risks, necessitating rapid and sensitive detection methods. In this study, a colorimetric DNA chimera biosensor was developed by integrating a bivalent split aptamer pair with G-quadruplex DNAzyme for highly sensitive NOR detection. Molecular docking studies were performed to identify the key binding regions, facilitating aptamer truncation and splitting. The bivalent strategy markedly enhanced binding affinity. The presence of NOR guides the self-assembly of the functional DNA chimera, activating the G-quadruplex/hemin DNAzyme to catalyze ABTS oxidation and generate colorimetric signals. The biosensor demonstrated a linear range of 3.75–960 nM and a limit of detection of 2.97 nM, with excellent specificity. When applied to real seafood samples, it showed good accuracy and repeatability with recovery rates of 87.87–112.59%, offering a reliable platform for rapid detection of fluoroquinolone residues in seafood.

Biomimetic synthesis of C-doped g-C3N4 spinous hollow microspheres from sunflower pollen with enhanced visible-light photocatalytic performance

Wenshi Liu,Baogang Wang

Synthesis of porous g-C3N4/La and enhanced photocatalytic activity for the degradation of phenol under visible light irradiation

Xinshan Rong,Fengxian Qiu,Jian Rong,Jie Yan,Hao Zhao,Xiaolu Zhu,Dongya Yang

A series of porous g-C 3 N 4 /La (PGCN/La) materials used as photocatalyst for the degradation of phenol were prepared by two steps. The photocatalysts were characterized by X-ray diffraction (XRD), UV–vis diffuse reflectance spectroscopy (DRS), thermogravimetry (TG), Brunauer–Emmett–Teller (BET), Scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). From the TEM morphology, the porous structure of g-C 3 N 4 could be successfully controlled; from BET results, BET specific surface area of porous g-C 3 N 4 (PGCN) sample increases with the increasing of urea mass ratio. Compared with PGCN material (PGCN-50), PGCN/La sample (PGCN-50/La-5) could exhibit an enhanced photocatalytic activity and has the best degradation efficiency of 98.6% within 50   min under visible light irradiation. Photocatalytic reaction follows the first-order model kinetics ; and PGCN-50/La-5 photocatalyst shows the largest reaction rate among all samples which is nearly 2.96 times higher than that of pure PGCN-50. The present work illustrates that the photocatalytic activity of porous g-C 3 N 4 was improved by the addition of La and PGCN-50/La-5 has potential application in the removal of phenol or other organic molecular from wastewater.

Investigate the suitability of g-C3N4 nanosheets ornamented with BiOI nanoflowers for photocatalytic dye degradation and PEC water splitting

P. Velusamy,Xinghui Liu,M. Sathiya,Norah Salem Alsaiari,Fatimah Mohammed Alzahrani,M. Tariq Nazir,Elangovan Elamurugu,M. Senthil Pandian,Fuchun Zhang

The two-step thermal polymerization and solvothermal approach is used to construct nano heterostructures of FCN and BiOI (bismuth oxeye iodide), both of which are Nobel metal-free materials. This work reports the effect nano-heterostructure on the micro-structural, light absorption capability, PEC properties and pollutant degradation efficiency of the synthesised heterostructures . The addition to that formation of FCN/BiOI nano-heterostructure enhances the solar light absorption. The FCN/BiOI nano heterostructure shows 10 times higher photocurrent density than the BCN nanostructure and 3.8 time higher that FCN. The FCN/BiOI has a high induced photo-current density (20.17 mA/cm 2 ) and H 2 evolution rate (3762 μmol h −1 cm −2 ) under solar light illumination (λ ≥ 420 nm) in comparison with the other. Furthermore, the photocatalytic performance of this material for the breakdown of methyl red dyes was much greater. Under solar light irradiation , the azo dyes were degraded in 90 min. The FCN/BiOI nano-heterostructure has a higher dye degradation efficiency of 97.91%. The rapid transport of photo-induced electrons in the FCN/BiOI nanocomposite is responsible for the improvement in PEC and PC performances. These impressive findings suggest that this nanocomposite might be used to facilitate the PEC water splitting and the PC degradation of MR in the presence of light. The current research provides insight on how to best tailor composition and structure for efficient FCN photo-electrocatalysis water splitting and Methyl red dye degradation.

Efficient Photocatalytic Reduction of U(VI) by a Heterostructured NiAl-LDH/Phosphorus-Modified g-C₃N₄: Performance and Mechanism

Feng Li,Dan Zhou,Yaoping Guo,Keng Xuan,Yingqi Wang,Ying Zheng,Xuegang Wang,Zhanxue Sun,Yadan Guo

The contamination of water by soluble hexavalent uranium (U(VI)) requires the development of highly active and stable treatment materials. This study presents a rational design for a heterostructured photocatalyst by coupling phosphorus-modified graphitic carbon nitride (PCN) with NiAl-layered double hydroxide (NiAl-LDH). The structural theory was that P-doping would tailor the optoelectronic properties of g-C₃N₄, while integration with NiAl-LDH would establish a synergistic system for concurrent adsorption and photoreduction. As anticipated, the P modification inhibited crystal growth and improved charge separation in g-C₃N₄, elevating its U(VI) reduction rate by 3.67-fold. The NiAl-LDH component provided a high-specific-surface-area substrate for pollutant enrichment. The resulting optimal NiAl-LDH/PCN composite formed a Type-II heterojunction, which directed efficient charge transfer between the two phases. Under simulated sunlight, the composite achieved high removal efficiencies of 96.0% for U(VI) and 95.2% for Cr(VI). The performance stems from a synergy where NiAl-LDH concentrates target ions at the interface, and PCN furnishes photogenerated electrons via facilitated charge transfer, thereby accelerating the photoreduction kinetics. The material also demonstrated robust reusability and effectiveness in treating actual wastewater, highlighting its strong potential for practical heavy-metal-ion remediation.

Constructing a Cu: MoO3/g-C3N4 heterostructure with broad visible-light response to enhance CO2-to-methanol conversion performance

RuoKun Jia,TianXiang Li,PengPeng Wang,DuMin Li,JiaHui Chen,XiaoHang Yang,QingXiao Zhao,Xin Cheng,LingYun Zhang,Xiaoxi Liu

A Cu: MoO 3 /g-C 3 N 4 binary heterojunction photocatalyst was synthesized via a hydrothermal method, achieving a light response that covers nearly the entire visible region. The material shows a strong, broad absorption band from 400 to 700 nm, significantly improving its visible-light harvesting and utilization efficiency. Optimization of the g-C 3 N 4 , Cu, and Mo molar ratios further enhanced the catalyst’s redox performance under visible-light irradiation. Through combined XPS, UV–vis, and in situ DRIFTS characterizations, it was verified that the Cu: MoO 3 /g-C 3 N 4 photocatalyst possesses a wide visible-light absorption range and effectively transforms absorbed long-wavelength photons into photogenerated electron-hole pairs, thereby facilitating the separation and transfer of charge carriers. Due to the simultaneous enhancement of broad-spectrum light capture and charge separation/transfer efficiency, this catalyst demonstrates excellent catalytic activity in visible light-driven CO 2 conversion, with a maximum methanol production rate of 102.52 μmol·g −1 ·h −1 . This work verifies the feasibility of efficient visible light-driven CO 2 conversion and provides a viable design approach and reference for constructing multi-metal-based photocatalysts with full visible light response.

Construction of ternary BiOBr/NH2-MIL-101(Fe)/g-C3N4 nanocomposite as an efficient photocatalyst for degradation of tetracycline

Zhao Xu,Guo Hongyan,Zhang Nannan,Yue Zhi,Gu Xungang

A novel dual Z-scheme BiOBr/NH 2 -MIL-101(Fe)/g-C 3 N 4 (BNG) heterojunction was constructed via a simple two-step solvothermal process. NH 2 -MIL-101(Fe) nanoparticles and BiOBr microspheres were uniformly deposited on the surface of g-C 3 N 4 . The prepared BNG exhibited significantly enhanced photocatalytic performance for tetracycline (TC) degradation compared to single catalyst. The optimized BNG-19 composite (with 19% NH 2 -MIL-101(Fe)/g-C 3 N 4 ) achieved 92.38% degradation of TC within 75 min under visible light, which was 2.47, 1.78, and 1.84 times higher than that of pure g-C 3 N 4 , NH 2 -MIL-101(Fe), and BiOBr, respectively. Moreover, the composite exhibited excellent stability with 82.4% removal efficiency after five cycles. The enhanced photocatalytic performance was attributed to the synergistic dual Z-scheme charge transfer mechanism, which was directly evidenced by in-situ irradiated XPS showing opposite directional shifts of Bi 4f (positive) and Fe 2p/N 1s (negative). This unique charge transfer pathway effectively promoted the separation of photogenerated carriers, with •OH and •O 2 ⁻ identified as the dominant reactive species. This work provides a new strategy for constructing g-C 3 N 4 -based dual Z-scheme heterostructures with direct mechanistic evidence for efficient environmental remediation.

Enhanced anti-fouling performance of PVDF hollow fiber ultrafiltration membranes for shale gas wastewater treatment using PVDF-g-PEGMA

Jiajia Fan,Jinyuan Hu,Shengchi Bai,Xifan Li,Guijing Chen,Jia Chen,Sheng Chen,Baicang Liu

Developing high-performance anti-fouling ultrafiltration membranes is essential for treating shale gas wastewater (SGW), addressing its severe membrane fouling issues. This study reports the fabrication of polyvinylidene fluoride (PVDF)/PVDF-graft-poly(ethylene glycol) methyl ether methacrylate (PVDF-g-PEGMA) blended hollow fiber membranes via non-solvent induced phase separation for direct treatment of SGW. The influences of the copolymer doping ratio on microstructure, chemical composition, and hydrophilicity were systematically investigated. The addition of PVDF-g-PEGMA contributed to a favorable membrane morphology and significantly improved hydrophilicity. The 20 wt% PVDF-g-PEGMA modified membrane achieved a 64.4% increase in pure water flux while retaining over 95.9% rejection for both humic acid and bovine serum albumin. More importantly, in long-term filtration of SGW, the modified membrane demonstrated a stable permeation flux of ~30.4 L·m −2 ·h −1 , surpassing the performance of the unmodified membrane by 300% and reducing the cost of water treatment for unit flux by 17.6%. Analysis based on the extended Dragun-Landau-Verwey-Overbeek theory indicated that the incorporation of PVDF-g-PEGMA effectively reduced the attractive interaction energy between the membrane and pollutants. These results demonstrate that the PVDF-g-PEGMA blending modification not only significantly enhanced membrane permeability and anti-fouling performance under challenging real wastewater conditions but also achieved sustained flux and superior anti-fouling behavior during lab-scale SGW operation, thereby enabling water reuse with reduced maintenance demand.

Oxygen vacancy-boosted 0D/2D BiOBr/g-C3N4 heterojunctions for efficient visible-light photocatalytic removal of 1-naphthoic acid

Yunlong Lan,Chao Deng,Qiaoping Kong,Chuanxi Yang,Bingrui Ma,Erling Zhao,Xiaoning Wang,Yongkun Wu,Liping Xiao

Nowadays, industrial wastewater contains abundant refractory organic pollutants, which seriously threaten ecological environment and human health. As an eco-friendly and efficient technology, photocatalysis is a promising approach for wastewater purification. Nevertheless, the rapid recombination of photogenerated carriers greatly limits the practical application of conventional photocatalysts. Introducing oxygen vacancies (OVs) into photocatalysts is an effective strategy to solve this problem and improve photocatalytic activity. In this study, we facilely synthesized 0D/2D BiOBr-OVs/g-C 3 N 4 heterojunction by a one-pot solvothermal method, which was composed of zero-dimensional (0D) oxygen vacancy BiOBr-OVs and two-dimensional (2D) g-C 3 N 4 components. The 0D/2D heterojunction exhibited enhanced visible-light degradation for the hazardous pollutant 1-naphthoic acid. And its removal rate by 0D/2D composites was up to 76.3% after 100 min of irradiation, which was 1.61 and 1.45 times those of 2D g-C 3 N 4 and 0D BiOBr-OVs. The noticeably increased removal efficiency of 0D/2D composites for 1-naphthoic acid was attributed to the rational utilization of oxygen vacancies to promote charge carrier separation. And the tight bonding between components also contributed to photoinduced carrier migration and exerted a synergistic effect for photocatalysis. Possible degradation pathways were proposed for the intermediates via gas chromatography-mass spectrometry (GC-MS) qualitative analysis, and their toxicity was evaluated using the Toxicity Estimation Software Tool (T.E.S.T.). This paper provides an innovative approach for one-step manufacture of 0D/2D nanojunctions with oxygen vacancies, and advances to prospective organic photodegradation applications.

Fabrication of bisphenol a imprinted polymers microspheres as an adsorbent via pickering emulsion polymerization stabilized with g-C3N4 nanosheets

Wang Zehu,Zhang Xiaoliang,Wang Yanming,Yue Xuan

As a typical endocrine disrupter, bisphenol A (BPA) could damage the reproductive and endocrine systems of humans and mammals. Therefore, the precise removal of BPA from the environment becomes increasing urgent. In this work, we employ Pickering emulsion polymerization to prepare the molecularly imprinted polymers (MIPs) microspheres through the non-covalent molecular imprinting strategy, which contain specific binding sites for the precise recognition of BPA. Graphite-carbon nitride (g-C 3 N 4 ) possesses a unique interfacial characteristic and is expected to develop potential application in the field of Pickering emulsion polymerization. In the process of polymerization, g-C 3 N 4 nanosheets are used as the sole emulsifier to build the Pickering oil/water emulsion system followed by the thermal-induced radical polymerization. The template molecules of BPA could be eluted from the polymer microspheres by continuous soxhlet extraction. The obtained MIPs microspheres were characterized with the help of optical microscope and field emission scanning electron microscope, respectively. The MIPs microspheres present regularly spherical structure with a relative broad size distribution. The formation of imprinted sites on the MIPs was validated through a batch of rebinding experiments, including the binding kinetics, binding isotherm, selective experiment and competitive experiment. The MIPs microspheres would have broad application prospect in environmental and analytical fields. Graphical abstract