APPLIED CATALYSIS B-ENVIRONMENTAL
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2024
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IF 20.2
Yingdong Hao,Yonghui Zhao,Chunlai Zhang,Xinqing Chen,Nannan Sun,Wei Wei
Achieving a high yield of oxygenates and inhibiting overoxidation remain challenging for CH 4 photooxidation. Here, we report a catalyst with enriched Ag-ZnO interfaces by using ZIF-8 as the precursor. The resulting Ag/Z-450 photocatalysts show extraordinary efficiency in the photocatalytic oxidation of CH 4 , a high liquid oxygenate yield of 57.88 mmol·g cat −1 (28.94 mmol·g cat −1 ·h −1 ) and a selectivity of ∼100 % were obtained over 3.0Ag/Z-450, with HCHO as the major product (41.04 mmol·g cat −1 , ∼71 % selectivity). Mechanistic studies revealed that ZnO and Ag species acted as electron donors and acceptors, respectively, which enhanced charge carriers transfer and separation. CH 4 and O 2 can be effectively activated to generate •CH 3 and reactive oxygen species (ROS), their following reaction led to formation of CH 3 OOH, which can be further converted to CH 3 OH and HCHO. This work contributes to the development of a “two-in-one” CH 4 photooxidation catalyst system that simultaneously achieves unparallel productivity and selectivity.
研究领域:
材料科学
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环境科学
·
化学工程
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产品关联
DOI
高影响因子
APPLIED CLAY SCIENCE
·
2023
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IF 5.6
Menghan Yu,Haiyan Wu,Yuhang Meng,Menghan Qu,Huaming Yang
Given the global proliferation of pathogenic microorganisms , there exists a pressing imperative to cultivate efficacious nanomaterials possessing antimicrobial attributes, thereby impeding the transmission of infectious diseases. Clay-based nanoparticles , due to their inherent properties, serve as optimal candidates for the creation of innovative antimicrobial agents, particularly for coating materials . In this study, ZnO nanoparticles were synthesized on talc surfaces and doped with Ag + , yielding an effective antimicrobial composite (Ag-ZnO/talc). The primary aim was to comprehensively evaluate the antimicrobial effectiveness, material compatibility, and biosafety of Ag-ZnO/talc, as well as its potential applications in antibacterial coatings . The finding underscored the remarkable antibacterial properties of Ag-ZnO/talc composites, chiefly through the generation of reactive oxygen species , leading to impairment of the bacterial membrane and leakage of nucleic acid content. A biosafety evaluation indicated minimal cytotoxicity, a low hemolysis rate, and negligible skin tissue reactions, thereby suggesting its suitability for human application. Furthermore, the incorporation of the antimicrobial agent Ag-ZnO/talc did not significantly alter the physicochemical characteristics of the coating, while maintaining an enduring antimicrobial effect for a duration of two months. These findings establish the potential of clay-based antimicrobials for effective and safe application in coatings, facilitating the development of antimicrobial coatings in diverse industrial and public health environments.
研究领域:
纳米材料科学
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微生物学
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毒理学
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材料科学与工程
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DOI
高影响因子
CARBOHYDRATE POLYMERS
·
2016
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IF 4.219
Zhong Lu,Jingting Gao,Qingfeng He,Jie Wu,Donghui Liang,Hao Yang,Rong Chen
Nano Ag/ZnO hybrid material has been considered to be a promising nanocomposites for biomedical application because it has enhanced antibacterial activity and low cytotoxicity. Here a sponge-like nano Ag/ZnO-loaded chitosan composite dressing was first synthesized via preparing a chitosan sponge by lyophilization process, followed by the incorporation of Ag/ZnO nanocomposites into chitosan sponge. The porosity, swelling, blood clotting and in vitro antibacterial activity against drug-sensitive and drug-resistant pathogenic bacteria were evaluated. The results demonstrate that the prepared composite dressing shows high porosity and swelling as well as enhanced blood clotting and antibacterial activity. Cytocompatibility test evaluated in vitro illustrates the very low toxic nature of the composite dressing. Furthermore, the in vivo evaluation in mice reveals that the chitosan-Ag/ZnO composite dressing enhances the wound healing and promotes re-epithelialization and collagen deposition. These results strongly support the possibility of using this novel chitosan-AgZnO composite dressing for wound care application.
研究领域:
生物医学工程
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材料科学
·
药理学
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产品关联
DOI
PubMed
高影响因子
Nanotechnology Reviews
·
2021
·Vol. 10
·期 1
·1349-1358
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IF 7.848
Xiaodong Chen,Zhong-Tao Yang,Nannan Wang,Xin Gao,Gang Wang,Chunyu Song,Yunfeng Liu,Lifeng Cui
ZnO nanomaterials with the stereochemical structure were becoming a research focus in the scope of photocatalytic materials, but the ZnO was sensitive to UV light rather than the solar light source, which considerably prohibited its extended application. ZnO nanomaterials coupled with other nanomaterials could generate the alternative composite heterojunction nanomaterials to promote the photocatalytic activity. Herein, we reported two facile and feasible synthesis methods to fabricate TiO 2 /ZnO cube nanocomposites and Ag/ZnO hollow spheres by hydrothermal reaction and chemical deposition, respectively. In this regard, these composited nanomaterials have been successfully fabricated with high purities, good morphology, and crystal structure. Noticeably, in contrast with TiO 2 /ZnO and Ag/ZnO bulk nanocomposites, the Ag/ZnO hollow spheres could offer the higher activity for RhB degradation under the visible light. Moreover, the photocatalytic performance of Ag/ZnO for RhB degradation could be improved synergistically, and the effect of RhB degradation was highest when the Ag mass ratio was modulated at 10% in the sample. Furthermore, it remained a high photocatalytic efficiency even after four cycles. This protocol provided an approvable approach to fabricate efficient photocatalysts with persistent photostability in the wastewater treatment process.
Graphical abstract
研究领域:
材料科学
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环境科学
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化学工程
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产品关联
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2021
·
IF 10.588
Jingjing Liu,Liuyang Zhang,Bei Cheng,Jiajie Fan,Jiaguo Yu
Timely detection of formaldehyde is pivotal because formaldehyde is slowly released from the indoor decorative materials, jeopardizing our healthy. Herein, a high-response formaldehyde gas sensor based on Ag-ZnO/In 2 O 3 nanofibers was successfully fabricated. Compared with all the control samples, the hybrid exhibits superior sensitivity (0.65 ppm −1 ), excellent selectivity (≥ 12.5) and durable stability (the deviation value ≤ 3%). Particularly, an ultra-high response value of about 186 towards 100 ppm of formaldehyde at 260 °C was achieved, heading the list of outstanding candidates. Additionally, the limit of detection is as low as 9 ppb. The enhanced gas sensing properties can be mainly attributed to multi-level heterojunctions (n-n heterojunction and Ohmic junction) and the “spill-over” effect of Ag, ultimately increasing the adsorption of gas molecules on the surface of sensing material. This work verifies that proper design of multi-level heterojunctions significantly upgrade the sensing performance.
研究领域:
材料科学
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环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2022
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IF 5.518
Yuanjie Xu,Shichao Yang,Meihui Ying,Xing Lin,Haibo Pan
Metal-organic frameworks (MOFs) are with extensive attention for environmental remediation due to their various modification and high density of active sites. Herein, a series of Ag/ZnO@ZIF-C with core-shell structure and graphene carbon (C) acts as a sandwich bridge were designed as a photocatalyst , accelerating the interfacial charge transfer rate between Ag and ZnO. Photocatalytic activities of Ag/ZnO@ZIF-C is remarkably improved toward rhodamine B (RhB) under UV irradiation , i.e., the degradation rate by Ag/ZnO@ZIF-C (20 wt%) is 2.27 times than that of P25. RhB molecules were simultaneously photodegraded at multiple sites, including N-site de-ethyl, conjugate structure and benzene ring . The photocatalytic upgrading performance was recognized to the synergetic interface between ZnO@ZIF-C and Ag nanoparticles (NPs) with effective separation and suppressed the recombination of electrons and holes. It is suggesting that the electrons in the valence band (VB) of ZnO are excited to the conduction band (CB) and transferred to Ag NPs through the ZIF-C layer, then react with adsorbed oxygen to create superoxide radicals and degrade RhB into small molecules. After a five-consecutive operation, its photocatalytic efficiency by Ag/ZnO@ZIF-C (20 wt%) still maintains at 95.11 %. This work provides a promising method for the rational design of high-performance carbon doped photocatalysts for environmental remediation.
研究领域:
环境科学
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材料科学
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产品关联
DOI
高影响因子
ARCHIVES OF ORAL BIOLOGY
·
2019
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IF 1.663
Qiaomu Huang,Shilei Wang,Yujun Sun,Cheng Shi,Hao Yang,Zhong Lu
Objective Streptococcus mutans ( S. mutans ), the main pathogen of dental caries, could be well killed by Ag/ZnO nanocomposite. However, effects on virulence factors remain to be elucidated. This study investigated effects of Ag/ZnO at sub-minimum inhibitory concentrations (sub-MICs) on virulence factors of S. mutans and related genes expressions. Design Effects of Ag/ZnO on the growth of S. mutans was investigated by growth curves and MTT staining method. The influence of Ag/ZnO at sub-MICs on biofilm formation was measured by the crystal violet staining method and observed by a scanning electron microscopy. Adherence, cell-surface hydrophobicity, acidogenicity and extracellular polysaccharides (EPS) of S. mutans after treatment by Ag/ZnO at sub-MICs were also investigated. Virulence factors related genes expressions after treated by Ag/ZnO at 1/2 MIC was conducted by the quantitative real-time PCR (qRT-PCR) method. Results Sub-MICs of Ag/ZnO exhibited a dose-dependent inhibition on the virulence factors of S. mutans . Specially, Ag/ZnO at 1/2 MIC decreased 69.00 % biofilm formation, 31.78 % sucrose-independent and 48.08 % sucrose-dependent adherence, 69.44 % cell-surface hydrophobicity and 72.45 % water-soluble and 90.60 % water-insoluble EPS. Furthermore, the expression of virulence factors related genes was significantly suppressed by Ag/ZnO at 1/2 MIC. Conclusions Ag/ZnO at sub-MICs inhibited multiple virulence factors of S. mutans through downregulating the related genes. Ag/ZnO nanocomposite could be used for prevention of dental caries at low dosage.
研究领域:
口腔微生物学
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纳米医学
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分子生物学
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DOI
高影响因子
Carbon Letters
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2024
·
IF 5.5
Liu Rui,Zhang Xin,Tan Chong
Environmental-friendly photocatalytic technology is attracting considerable attentions in the filed of antibiotic degradation. In this work, an innovative Ag/ZnO/Bi 2 WO 6 catalyst was fabricated using sol–gel and ultrasonic methods for the degradation cefuroxime sodium in wastewater. The optimized Ag/ZnO/Bi 2 WO 6 photocatalyst demonstrated the a remarkable 77.0% photocatalytic efficiency within 180 min under simulated solar sunlight, with an apparent rate constant of 0.01085 min −1 . This efficiency is notably 6.02 and 1.41 times higher than that of pure ZnO and Ag/ZnO, respectively. The Ag/ZnO/Bi 2 WO 6 photocatalyst achieved a degradation efficiency of up to 72.3% in tap water and polluted river water, while achieving 65.7% degradation in pulping wastewater and pharmaceutical wastewater. Experiments involving reactive species scavenging and electron paramagnetic resonance implied that hydroxide radicals were the predominant active species responsible for the degradation. The enhanced catalytic mechanism and degradation pathway were elucidated, providing valuable insights into the construction and development of high-performance catalysts based on zinc oxide.
研究领域:
环境科学
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材料科学
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化学工程
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产品关联
DOI
高影响因子
SOLID STATE SCIENCES
·
2022
·
IF 3.752
Jyunhong Shen,Antong Shi,Mengfan Wu,Hongyu Zhang,Zhuwu Jiang
For the advanced treatment of micropollutants from wastewater, this study synthesized a ternary Ag/ZnO/ZnAl‒LDH composite photocatalyst with performance optimization based on the Taguchi approach. The optimal synthesis parameters were statistically determined as the Ag doping amount of 5 wt%, Zn 2+ and Al 3+ with a molar ratio of 3:1, Ag/ZnO and ZnAl‒LDH with composite ratio of 3:2, and PEG-200 dosage of 25 mL. The optimally synthesized Ag/ZnO/ZnAl‒LDH achieved the efficient degradation of bisphenol A (BPA) under visible light irradiation, and the reaction rate constant was about 4.8-, 2.2- and 12.0-fold higher than that of ZnO, Ag/ZnO and ZnAl‒LDH, respectively. As proved by various characterizations, the enhanced photocatalytic performance of Ag/ZnO/ZnAl‒LDH can be attributed to the improvements of optoelectronic properties, such as the widened visible light responsivity and facilitated charge transfer, thus resulting in a significant increase of hydroxyl radicals (·OH) formation. Fluorescence measurements and radical quenching experiments indicated that ·OH mainly contribute to the degradation of BPA, and the oxidation of H 2 O by holes was the dominant formation pathway. According to the above results, this study summarized and proposed the enhanced photocatalytic mechanism of Ag/ZnO/ZnAl‒LDH for ·OH production and BPA removal.
研究领域:
环境科学
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材料科学
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产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2023
·
IF 7.7
Wenqiang Liu,Meng Zhou,Heqing Fu
A ternary Ag@ZnO@Ti 3 C 2 MXene heterojunction (AZM) is synthesized by hybridizing ZnO and Ag nanoparticles with the MXene via a simple hydrothermal and chemical deposition method. The addition of ZnO and Ag can effectively compensate for MXene’s narrow bandgap property, promote charge carrier separation, and improve visible light absorption , thereby enhancing photocatalytic activity. The photocatalytic activity of the AZM is evaluated through the removal efficiency of methylene blue (MB) dye and levofloxacin (LVX) under visible light irradiation. The results show that the optimized ternary AZM heterojunction photocatalysts (AZM-15) possesses the maximum degradation of MB (90.54%) with a reaction rate constant of 0.0473 min −1 , while the maximum degradation of LVX (86.76%) has a reaction rate constant of 0.0408 min −1 . Moreover, the AZM composite exhibits excellent stability, which explains its MB removal rate of 83.59% and LVX removal rate of 80.03% after five cycles. The results of trapping experiments and EPR demonstrated that the main active species in the MB and LVX photodegradation process are·OH and·O 2 - . This work not only elucidates a possible mechanism of photocatalytic degradation of organic pollutants but also provides a pathway to design new bandgap photocatalysts for mitigating environmental pollution .
研究领域:
材料科学
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环境科学
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产品关联
DOI
高影响因子
JOURNAL OF MATERIALS RESEARCH
·
2016
·Vol. 31
·期 4
·468-479
·
IF 1.579
Zhijun Wei,Lingjie Zhang,Hui Yang,Tao Shen,Lawson Chen
Two kinds of Ag/ZnO electrical contact materials were fabricated by powder metallurgy method. The electrical life testing was done to investigate the arc erosion behavior of the prepared contact materials. Their properties and morphologies were characterized and discussed in detail. Results showed that Ag/ZnO(c) with coprecipitated ZnO as the second phase had better mechanical and electrical properties compared with Ag/ZnO(a) with ZnO purchased from Aladdin Industrial, Inc. Besides, some typical morphologies, such as holes, Ag or ZnO enrichment zone, Ag skeletons and bubbling area, occurred on the surface of the contacts. Especially for Ag/ZnO(c), vertically aligned ZnO nanorod arrays were detected after the life testing without any other supporting equipment. The existence of a solid solution Zn1−x
Ag
x
O and different energy generated during arcing process were possible reasons resulting in this phenomenon. A solid–vapor–solid mechanism was put forward to analyze the phenomenon mentioned above. These evidences could also offer some valuable information desired for reducing the splashing of Ag droplet under arcing.
研究领域:
材料科学
·
电气工程
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产品关联
DOI
高影响因子
CELLULOSE
·
2022
·Vol. 29
·期 4
·2289-2304
·
IF 6.123
Shi Chun,Zhang Lili,Shi Zhengjun,Zai Zhenqiang,Ma Jinxia,Wang Zhiguo
Ag–ZnO/cellulose nanocomposites with an all-weather photocatalytic performance that responds to all light conditions (including ultraviolet light, visible light, and even darkness) were fabricated by adjusting the surface groups and aspect ratios of the cellulose nanofiber substrate. The cellulose nanofibers improved the dispersibility and photostability of the Ag–ZnO nanoparticles (NPs), thereby enhancing the photocatalytic activity. The morphologies and sizes of the ZnO and Ag NPs within the Ag–ZnO/cellulose nanocomposites were controlled by using cellulose nanofibers with different surface groups and aspect ratios. ZnO NPs with average diameters of 250, 500, and 100 nm were synthesized in situ using cellulose nanocrystals (CNCs), cellulose nanofibrils (CNFs), and TEMPO-mediated oxidized cellulose nanofibrils (TOCNFs), respectively. The Ag–ZnO/TOCNF nanocomposites exhibited excellent all-weather photocatalytic performance, high loading amounts, and large effective contact area with pollutants. Free radical trapping experiments demonstrated that ·OH had the most significant effect on the photocatalytic activity. The photocatalytic activity of the Ag–ZnO/TOCNF nanocomposites was improved by preventing the recombination of electrons and holes and increasing the contact area with pollutants and light. The photogenerated electrons stored on the surface of the ZnO NPs and Ag NPs were further used for reducing H 2 O 2 to generate ·OH free radicals in the dark, which continued to catalyze the degradation of pollutants without light irradiation. Moreover, the photocatalytic degradation of methyl orange to CO 2 and H 2 O was confirmed via a catalytic mechanism and liquid chromatography–mass spectrometry.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子