查找使用阿拉丁产品的科研文献

Constructing carboxylated cellulose nanofibers/chitosan aerogel loading with CdS/UiO-66-NH2 for wastewater treatment: Synergistic adsorption and visible light photocatalytic degradation

Ziyao Mi,Xuzhen Liu,Yue Zhang,Bo Wang,Hongyu Guo,Yufeng Chen,Yanyan Du,Xinyu Wang,Xiaojun Hu,Jingxian Jiang

The discharge of industrial effluents containing heavy metal ions and organic dyes has laid heavy burdens on ecosystem, meanwhile, drawing extensive scientific attention globally. In this work, CdS/UiO-66-NH 2 heterojunction was uniformly loading on the aerogel skeleton composed of cellulose (CNF), chitosan (CS) and montmorillonite (MMT). The fabricated composite aerogel noted as CUN-CCMA was equipped with light density, a large specific area and a robust three-dimensional interpenetrating network. The MMT not only reinforced the mechanical stability of the aerogel, but also regulated the distribution of the heterojunction. The CUN-CCMA could adsorb various organic dyes and heavy metal ions, and the maximum adsorption capacities for methylene blue (MB) and Cu 2+ were 111.5 mg/g and 45.1 mg/g, respectively. The corresponding adsorption processes were in better consistence with the pseudo-second-order kinetic model and the Freundlich isotherm. The hydrogen bonding, electrostatic interaction, π-π stacking and chelating effect might be attributed to the adsorption mechanism. Most importantly, the removal efficiency of MB with a high concentration of 300 mg/L could reach 94 % when synergistic effect of adsorption and visible light photocatalytic degradation was exerted. The active species that played vital roles during the photodegradation process were recognized as ·OH and · O 2 − . Furthermore, the CUN-CCMA demonstrated an excellent reusability. These outstanding characteristics of CUN-CCMA broadened its application prospects in complicated sewage treatment.

NH2-MIL-125(Ti) encapsulated with in situ-formed carbon nanodots with up-conversion effect for improving photocatalytic NO removal and H2 evolution

Youzhou He,Shuang Luo,Xueli Hu,Yaling Cheng,Yumin Huang,Shengming Chen,Min Fu,Yiming Jia,Xingyan Liu

The bifunctional photocatalyst CDs@NH 2 -MIL-125(Ti), carbon nanodots (CDs) encapsulated in NH 2 -MIL-125(Ti), was constructed in situ by a simple and convenient low-temperature calcination approach, which exhibited great capacity in NO removal (at air level) and H 2 evolution simultaneously under visible-light irradiation. The NO removal rate of CDs@NH 2 -MIL-125(Ti) (10 mM) reached 53%, which was 28.4% higher than pristine NH 2 -MIL-125(Ti). Moreover, the H 2 production rate was 5820.95 μmol g −1 , which was 5.34 times higher than that of original NH 2 -MIL-125(Ti). The corresponding optical and electrical performances of CDs@NH 2 -MIL-125(Ti) characterized by UV–Vis, UCPL, ESR, and in situ DRIFTS , etc. indicated that the encapsulated CDs uniformly dispersed in the pores of NH 2 -MIL-125(Ti) could improve the visible light utilization via the up-conversion effect and photosensitization, and serve as an electron-receiver to significantly prolong the lifetime of the photogenerated charge carriers, thus enhancing the photocatalytic performance. The results revealed that fabricating CDs with metal-organic frameworks (MOFs) could be an available strategy for us to boost the photocatalytic NO elimination and H 2 evolution activity simultaneously.

In-situ silver-bridged interfaces drive Z-scheme coupling on iron-doped NH2-UiO-66(Zr)/silver iodide for efficient aqueous antibiotic degradation

Haileyesus Hatano Haitosa,Osman Ahmed Zelekew,Pu Chen,Daniel Manaye Kabtamu,Weimao Yan,Hong Wang,Yi-nan Wu

Fluoroquinolone antibiotics like ciprofloxacin (CIP) pose environmental risks when released into water. Herein, a visible-light-active Fe-doped NH 2 -UiO-66(Zr)@AgI Z -scheme heterostructure was prepared via an ion exchange precipitation method. By varying AgI content, reduced particle size and enhanced charge separation for efficient photodegradation was achieved. The optimum composition (Fe-UNH@AgI-20) exhibited a 95.2 % degradation efficiency toward CIP after 60 min of visible-light irradiation. It also showed high removal efficiencies for tetracycline, lomefloxacin, and Rhodamine B. Reaction kinetics followed pseudo-first-order behavior, with rate constants significantly higher than those of pristine NH 2 -UiO-66(Zr) and AgI. The catalyst maintained 85.1 % activity after cycles, indicating good stability. Scavenger tests and electron paramagnetic resonance (EPR) analyses identified holes (h + ), superoxide radical (•O 2 − ), and hydroxyl radical (•OH) as key reactive species. Fe doping enhanced visible-light absorption and created defect sites, while AgI introduction promoted charge separation and suppressed AgI photocorrosion. Under irradiation, a small fraction of Ag + was reduced to metallic Ag, forming an electron bridge that switched the initial type-II heterojunction to a Z -scheme configuration. This Z-scheme mechanism efficiently separated carriers, facilitated generation of ROS, and enabled thorough mineralization of CIP; toxicity predictions showed most products were less mutagenic than CIP, confirming reduced ecological risk. The findings demonstrate that the Fe-doped NH 2 -UiO-66(Zr)@AgI heterostructure is a promising photocatalyst for antibiotic-contaminated wastewater remediation.

Enhanced photocatalytic CO2 reduction over diatomite-supported TiO2@NH2-MIL-125 S-scheme heterojunction: Intensified charge separation driven by built-in electric field

Yi Wen,Chenguang Qian,Xiaohan Li,Ruizhe Sang,Fang Yuan,Chunquan Li,Zhiming Sun

The development of heterojunction photocatalysts is pivotal in enhancing charge transfer and inhibiting the recombination of photoexcited electron-hole pairs, which is an effective strategy to improve CO 2 conversion. In this study, we have been assembled the TiO 2 @NH 2 -MIL-125 S-scheme heterojunction on the surface of diatomite. Comprehensive characterization confirms the S-scheme charge transfer pathway, which not only promotes preferential accumulation of photogenerated charges at catalytically active sites but also enables rapid, low-resistance charge separation and migration. Meanwhile, the introduction of diatomite improves the dispersion of the active components and accelerates the separation of photogenerated carriers driven by the built-in electric field. Consequently, the TiO 2 @NH 2 -MIL-125/diatomite composite exhibits selective photocatalytic CO 2 to CO conversion without requiring sacrificial reagents. The composite achieves a CO evolution rate of 13.53 μmol g −1  h −1 , which is 2.20 times and 1.33 times higher than pure TiO 2 and the binary TiO 2 @NH 2 -MIL-125 composite, respectively. Furthermore, the composite maintains a stable CO production rate after three reaction cycles. This study presents an approach to designing mineral-supported S-scheme heterojunction photocatalysts for solar energy conversion applications.

High-loading red carbon dots@NH2-MIL-53(Al) composite for ultrasensitive and selective picric acid detection via synergistic FRET and competitive absorption

Jie Hu,Hui Chen,Ruibin He,Pran Gopal Karmaker,Xiupei Yang,Fenglin Tang

Rapid and sensitive detection of picric acid (PA), a highly toxic and water-mobile nitroaromatic pollutant, is essential for environmental safety and public health protection. Herein, we fabricate a dual-emission ratiometric fluorescent probe by immobilizing high-load red-emitting carbon dots (R-CDs) onto NH₂-functionalized MIL-53(Al), forming an R-CDs/NH 2 -MIL-53(Al) composite for selective aqueous-phase PA sensing. R-CDs were hydrothermally synthesized with citric acid and neutral red as co-precursors. The loading efficiency was   maximized by systematically optimizing precursor molar ratios and dilution conditions. The composite exhibits distinct selective fluorescence quenching in the presence of PA. Mechanistic characterizations, including fluorescence lifetime decay measurements and spectral overlap analysis, verify that the fluorescence quenching originates from two synergistic quenching pathways, namely competitive light absorption and fluorescence resonance energy transfer (FRET), rather than nonspecific physical interactions. This ratiometric sensing platform achieves a wide linear detection range of 0.1–70 μM and an ultralow limit of detection (LOD) of 32.9 nM. Spike-and-recovery assays using real environmental water samples (tap water, commercial bottled mineral water, and Jialing River surface water) produced recoveries of 99.7%–105.1%, with relative standard deviations (RSD) below 5.86% ( n  = 3). Furthermore, a smartphone-enabled visual quantitative method based on RGB color channel analysis was constructed, enabling portable on-site detection without large-scale laboratory instrumentation.

Preparation and performance study of SPEEK/S-GO/NH2–SiO2/PPS composite proton exchange membrane based on acid–base cooperative topological conductive network

Maliang Zhang,Linlin Wang,Shuo Yang,Mengen Zhang,Ziang Mu,Yaru Wang,Xi Du,Zhenhuan Li,Bowen Cheng

This study uses polyphenylene sulfide (PPS) fiber paper as a skeletal support to fabricate a high-density, porous nonwoven support layer with excellent mechanical stability via wet papermaking. Sulfonated polyether ether ketone (SPEEK) is then cast onto its surface to form a continuous proton-conducting phase. Building on this foundation, synergistic doping with sulfonated graphene oxide (S-GO) and amino-modified silica (NH 2 –SiO 2 ) constructs a topologically interconnected proton exchange membrane structure exhibiting acid-base synergistic effects. The sulfonic acid groups on the S-GO surface act as high-density proton donors, providing continuous proton conduction sites. Meanwhile, the basic amino groups in NH 2 –SiO 2 form stable acid-base interactions and hydrogen-bond networks with sulfonic acids, effectively anchoring proton migration pathways, reducing disordered swelling, and extending proton hopping distances. This topologically interconnected acid-base synergistic network significantly enhances proton transport dominated by the Grotthuss mechanism while effectively suppressing methanol permeation. Performance testing reveals that the composite membrane with optimized doping ratio achieves proton conductivity up to 0.2 S cm −1 at 80 °C, with methanol permeability significantly lower than commercial Nafion-117 membranes. In direct methanol fuel cell testing, the composite membrane exhibited an open-circuit voltage of approximately 770 mV and a peak power density approaching 170 mW cm −2 , while demonstrating excellent thermal stability, oxidation resistance, and mechanical strength. These results demonstrate that constructing a topologically interconnected structure with synergistic acid-base interactions can effectively balance proton conductivity and fuel barrier performance, providing a viable new strategy for developing high-performance, low-cost proton exchange membrane materials.

In Situ Determination of Chloride Ions Using a Novel Double-Layer Membrane Optical Fiber Sensor Modified with the UiO-66-NH2/Lucigenin Complex

Chloride quantification is crucial for environmental monitoring, marine research, and the durability assessment of geotechnical infrastructures, yet accurate measurement in complex aqueous and soil matrices remains challenging. Optical fiber sensors offer distinct advantages, including resistance to electromagnetic interference, high sensitivity and low cost. Unfortunately, existing fiber-optic chloride sensors are often limited by insufficient sensitivity, poor anti-ion interference, inadequate portability, and an inability to perform long-term in situ monitoring. Herein, a novel fluorescent optical fiber chloride sensor based on UiO-66-NH2/lucigenin composite is fabricated, in which the mixture formed lucigenin encapsulated with UiO-66-NH2is immobilized within a dual-layer membrane composed of an inner cellulose acetate (CA) matrix and an outer polyvinyl alcohol (PVA) membrane. The chloride-responsive fluorescent probe operates on the principle of fluorescence quenching. The dual-layer sensitive membrane is engineered to significantly enhance sensitivity, linearity, and stability for long-term monitoring. Furthermore, the portable device eliminates the constraints of bulky optical systems and mitigates instability caused by photobleaching, enabling reliable in situ chloride detection in water, soil, and geotechnical environments. Experimental results confirm the superior analytical performance of the sensor across various soil and aquatic media. This work represents a notable advancement in the field of fluorescent optical fiber sensors and holds substantial promise for practical applications.

Bifunctional confinement strategy for sintering-resistant Ag catalysts: synergy of B2O3 electrophilicity and NH2-spacial limitation in steering C = O bond activation dynamics

Aidi Xie,Wusong Geng,Chun Chen,Yunxia Zhang,Haimin Zhang,Guozhong Wang

A mesoporous SiO 2 -supported Ag catalyst co-modified with B 2 O 3 and amino groups (B/Ag@NH 2 −MS) was synthesized through the grafting of amino group onto silica and subsequent impregnation with 10 wt.% Ag and 5 wt.% B 2 O 3 . Density functional theory (DFT) calculations and Bader charge analysis showed that boron (B) doping triggered extensive electronic changes in the modified support. It implied that B atoms gained a partial positive charge, showing Lewis acidic nature, while nearby Ag atoms had a partial negative charge. This electronic redistribution led to a downward movement of the Ag d -band center and a decrease in the work function, which in turn modulated the binding energies of adsorbates and reduced the desorption barrier of MG. Such dual-site cooperation strengthened the adsorption and polarization of the DMO carbonyl group at the adjacent Ag and B sites, thus promoting the activation of the C = O bond. Moreover, the anti-sintering capacity of Ag nanoparticles could be ascribed to their efficient stabilization mechanism, resulting from the synergistic action of oxygen-bridged B/O/Ag species and –NH 2 functional groups.Consequently, it is noted that the catalyst is able to maintain a conversion of about 99% DMO and a selectivity of about 94% MG, and it was able to maintain a conversion rate of over 96% for >350 h. These observations highlight a dual-site electron synergy strategy for developing very active and long-lasting Ag catalysts for ester hydrogenation.

Controllable Preparation of Novel UiO-66-NH2/g-C3N5 Thin-Film Nanocomposite Nanofiltration Membranes with Efficient Photocatalytic Pollutant Removal and Anti-Fouling Ability

Tian Jianghao,Xiao Min,Li Shifeng,Bu Ruiying,Yang Xin,Zhang Hongling,Chen Xiaoyang

To overcome membrane permeation selectivity defects and mitigate membrane fouling, a novel nanocomposite, UiO-66-NH 2 /g-C 3 N 5 (UNCN), was designed and synthesized. Notably, this composite overcomes the inherent limitations of UiO-66-NH 2 (limited visible light absorption) and g-C 3 N 5 (low specific surface area). The optimal composite ratio was determined to be 3:7 through systematic optimization. The UNCN-3:7 nanocomposite was then embedded into the polyamide selective layer on polysulfone via in situ interfacial polymerization under optimal conditions, resulting in a thin film nanocomposite (TFN) Nanofiltration membrane. Characterization revealed that the UNCN-3:7 Nanocomposites were uniformly distributed within the polyamide (PA) matrix. The resulting TFN Nanofiltration membrane possessed an ultrathin, positively charged selective layer with enhanced hydrophilicity, evidenced by a reduction in water contact angle from 60.3° to 47.3°. It exhibited a 43% increase in pure water permeability compared to the unmodified thin film composite (TFC) membrane (52.7 vs. 36.9 L·m −2 ·h −1 ·bar −1 ), while maintaining an excellent Na 2 SO 4 retention rate (> 96%). Furthermore, the membrane demonstrated excellent photocatalytic degradation performance, superior anti-fouling properties (flux recovery rate > 92%), and stable long-term operation. These results indicate that the construction of the novel UNCN nanocomposite Nanofiltration membrane presents an effective strategy to address membrane fouling issues.

Building of soft-hard compound brush in porous PVA/NH2@TAtZnO plural gel and the high-efficiency anti-interference removal on Pb(II)

Lingli Liu,Sheng Xu,Zhenxi Wang,Xiaoguang Chen,Meng Cao,Shangxi Zhang,Yang Liu,Jinlong Cui

In order to promote the heavy metal ions removal of porous gel adsorbent and protect the adsorbent from other pollutants in wastewater, the tetrapod ZnO whiskers (tZnO) modified by amino-chain brush was introduced into the polyvinyl alcohol (PVA) matrix to prepare the PVA/NH 2 @TAtZnO composites with brush structure for toxic Pb(II) removal. The adsorption property, adsorption process and adsorption mechanism were studied by adsorption isotherms, adsorption kinetics, adsorption thermodynamics, SEM-EDS analysis and XPS analysis. And the anti-interference ability and anti-interference mechanism were researched by SEM-EDS analysis and XPS analysis. It was found that the PVA/NH 2 @TAtZnO composites displayed a soft-hard compound pore-brush structure and showed a good selective adsorption on Pb(II). The research of isotherms and kinetics indicated that the adsorption process was fitted well to Langmuir model and pseudo-second-order model, respectively, and the research of thermodynamics revealed the endothermic nature. The adsorption mechanism was inferred as the combination of predominant chemisorption and subsidiary physisorption. Comparing with the neat PVA matrix, the PVA/NH 2 @TAtZnO composites displayed a good anti-interference property on Pb(II) adsorption and showed an alleviative clogging pore-canal structure in the wastewater with SiO 2 NPs or PAC flocculants . The anti-interference intensity ΔQ and anti-interference factor χ were proposed to reflect the anti-interference ability of this adsorbent which was promoted with the increasing amino brush length or density. By the analysis of SEM-EDS and XPS, the anti-interference mechanism was explored as the steric-hinerance effect of tZnO hard brush to suspended SiO 2 NPs pollutant and the coordination effect of functional amino soft brush to soluble PAC pollutant. Besides, the prepared PVA/NH 2 @TAtZnO adsorbent possessed a good reusability under multiple adsorption-desorption processes and also presented a well applicability in real water matrix. The research indicated the huge potential of prepared PVA/NH 2 @TAtZnO adsorbent in heavy metal ions removal.

Efficient and selective removal of Cr(VI) by the modified UiO-66-NH2 with phenothiazine-N-rhodanine from aqueous solution: Performance and mechanisms

Hao Wang,Shuai Wang,Shixing Wang,Libo Zhang,Yang Zhou,Fan Yang

In the past decades, due to the worst effect of hexavalent chromium on human and environmental health, people have been committed to removing hexavalent chromium from industrial wastewater. In recent years, metal organic frameworks (MOFs) adsorbents have attracted more and more attention in the removal of pollutants from water. Here, an efficient and selective adsorbent(UiO-66-PRAA) was prepared by modified UiO-66-NH 2 with phenothiazine-N-rhodanine to remove Cr(VI) ion from wastewater. The maximum absorption capacity of UiO-66-PRAA at 303 K and pH = 2 was 333.67 mg/g for Cr(VI). Which is higher than that of bare UiO-66-NH 2 . Elovich kinetic and Sips isotherm models are more suitable for describing the adsorption process of Cr(VI) on UiO-66-PRAA, which indicates that the process is a chemically controlled multilayer adsorption. In addition, the removal mechanisms include chelation, ion exchange and reduction. The adsorbent still shows good adsorption performance under the coexistence of different ions. The excellent cycle performance of UiO-66-PRAA confirms its high potential in removing Cr(VI) from polluted water. In general, UiO-66-PRAA has been shown well adsorption properties and reusability, and our finding might provide a new idea for developing efficient and reusable adsorbent to remove Cr(VI) from wastewater.

Introduction of cluster-to-metal charge transfer in UiO-66-NH2 for enhancing photocatalytic degradation of bisphenol a in the existence of peroxymonosulfate

Shi-Wen Lv,Xiaoran Wang,Xing Wei,Yi Zhang,Yanqing Cong,Lin Che

Nowadays photocatalysis assisted advanced oxidation processes exhibited a great application prospects in pollution control. Herein, for the first time, a series of transition metal modified UiO-66-NH 2 (namely Fe-UiO-66-NH 2 , Co-UiO-66-NH 2 and Ni-UiO-66-NH 2 ) were synthesized via a simple method. After that, these functional materials were employed as photocatalyst to activate PMS for degrading BPA under visible light irradiation. Significantly, prepared Fe-UiO-66-NH 2 exhibited the highest photocatalytic activity among these samples. More importantly, proposed Fe-UiO-66-NH 2 /PMS/light oxidation system showed excellent degradation ability for various organic pollutants, including BPA, TC, OFX, IBP as well as SMX. Owing to the occurrence of d-d transitions after the coordination of transition metal ions, UiO-66-NH 2 displayed the enhanced utilization efficiency of visible light. Furthermore, introduced Fe ion as a mediator could boost the charge transfer by the cluster-to-metal way, thereby effectively inhibiting the recombination of photogenerated electrons and holes. In addition, embedding cluster-to-metal charge transfer in UiO-66-NH 2 modified the band structure, and both SO 4 −• and OH were major active species in the photocatalytic reaction system. Developed Fe-UiO-66-NH 2 /PMS/light oxidation system with good stability also presented great antibacterial performance. To sum up, current work could provide some novel inspirations for designing the high-efficiency photocatalyst.