RESEARCH ON CHEMICAL INTERMEDIATES
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2018
·Vol. 44
·期 5
·3061-3079
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IF 1.674
Wang Junxiu,Chen Kuan,Shen Yi,Wang Xi,Guo Yongfu,Zhou Xiaoji,Bai Renbi
Abstract To heighten the absorption to visible light and improve photocatalytic degradation to organic pollutants, a novel photocatalyst of m-Bi 2 O 4 /Bi 2 O 2 CO 3 was constructed through a facile hydrothermal method. The crystal structure, optical properties, morphology, composition and photocatalytic ability of the photocatalysts were characterized via X-ray diffraction, Fourier transform infrared spectroscopy, ultraviolet–visible diffuse reflectance spectroscopy, field emission scanning electron microscopy, energy dispersive spectroscopy, transmission electron microscope (TEM), high resolution TEM, selected-area electron diffraction and X-ray photoelectron spectroscopy technologies. The as-prepared photocatalysts could efficiently degrade rhodamine B and mixed dye under visible light. The removal rate was up to 95.3% within 50 min. The results demonstrated that m-Bi 2 O 4 /Bi 2 O 2 CO 3 photocatalysts showed outstanding photocatalytic degradation ability compared to the single photocatalyst with the narrow band gap. In addition, photocurrent response tests certified that the heterostructure of the photocatalysts effectively accelerated the separation and migration of photo-induced electrons and holes. Active species trapping experiments indicated that holes (h + ) and superoxide radical (•O 2 − ) were major species rather than hydroxyl radicals (•OH) during the degradation process of organics. According to the test results, a probable photocatalytic mechanism was proposed. This work provided a new and efficient photocatalyst for environmental remediation and water treatment. Graphical Abstract
研究领域:
环境科学
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材料科学
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化学
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2020
·
IF 10.652
Jianan Yu,Zhiliang Zhu,Hua Zhang,Xiaolin Shen,Yanling Qiu,Daqiang Yin,Shaobin Wang
Metal-free carbocatalysts are raising increased interest in advanced oxidation processes (AOPs) for green degradation of aqueous organic pollutants. In the present study, a series of N-doped hydrochars (NHCs) was prepared from pinewood biomass and used in carbocatalysis toward catalytic peroxymonosulfate (PMS) activation to degrade refractory endocrine disrupting compounds. Nitrogen-doping was found to regulate the concentrations and types of persistent free radicals (PFRs) on hydrochar, promoting the electron transfer and oxidative degradation of the contaminants. Mechanistic studies revealed that graphitic N not only shows a strong electron transfer to facilitate PMS activation in a nonradical pathway, but also induces the formation of oxygen-centered PFRs from the structure defects for a radical oxidation pathway. More importantly, the PMS/NHC system demonstrates efficient degradation and satisfactory stability for real water treatment. This study has gained in-depth understanding on the roles of N-dopants in radical and nonradical pathways of biomass-based carbocatalysis, and will provide a promising and environmental-friendly route for efficient degradation of refractory endocrine disrupting compounds for green remediation.
研究领域:
环境科学
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催化化学
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DOI
高影响因子
Journal of Cleaner Production
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2020
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IF 7.246
Donghai Yuan,Linxiao Zhai,Xueyao Zhang,Yanqi Cui,Xinyi Wang,Yinxiu Zhao,Hongdeng Xu,Liansheng He,Chenling Yan,Rong Cheng,Yingying Kou,Junqi Li
The nano zero valent iron (nZVI) is an efficient environmental remediation material, but it is easy to be oxidized and agglomerated, which limits its application in the environment. In this paper, bacterial cellulose membrane was used as a carrier material to reduce three different concentrations of ferrous ions by in-situ liquid-phase reduction method using sodium borohydride , and three kinds of bacterial cellulose membrane loaded with nanometer zero valent iron (BC-nZVI) samples were successfully prepared. The physical and chemical properties of BC-nZVI before and after the reaction were characterized by SEM, XRD and XPS . The effects of pH, dose and reactive oxygen species (ROS) on the inactivation of bacteriophage MS2 were studied. The results showed that nano-zerovalent iron was successfully loaded on the bacterial cellulose membrane. The particle size of nZVI particles loaded in BC-nZVI was about 200 nm under the condition of low ferrous sulfate, effectively alleviating the agglomeration phenomenon. And the inactivation efficiency of BC-nZVI on MS2 has been improved, reaching 4 log in 5 min. BC-nZVI showed two stages of inactivation characteristics, the first stage was 5 min to achieve 4 log high-efficiency inactivation stage, the second stage was the follow-up slow inactivation stage. At different pH value, the removal rate of MS2 by BC-nZVI increased with the increase of pH value, which was different from that of nZVI. The radical scavenger experiments showed that the main factor affecting the removal rate of MS2 in the first stage was •O 2 − , followed by Fe (IV), while the effect of •OH was not significant. In the second stage, the main influencing factors was •OH. Under alkaline condition, the yield of •O 2 − was increased, the reaction time was prolonged, and the deactivation rate of MS2 was increased. These results provide new ideas for the practical application of nZVI in the treatment of pathogenic microorganisms .
研究领域:
环境科学
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微生物学
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DOI
高影响因子
WATER RESEARCH
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2021
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IF 11.236
Lifa Ge,Yamei Yue,Wei Wang,Fatang Tan,Shenghua Zhang,Xinyun Wang,Xueliang Qiao,Po Keung Wong
Currently existing Fenton-like catalysts were limited in wastewater treatment owing to their potential transition-metal poisoning, narrow applicable pH range and high dependence on external energy excitation. In this work, the MgNCN/MgO nanocomposites were firstly synthesized by a facile one-pot calcination of melamine and basic magnesium carbonate, and used as novel H 2 O 2 activator for antibiotic removal. It was found that the MgNCN/MgO composite calcined at 550°C with the mass ratio of melamine to basic magnesium carbonate at 2:1, exhibited an excellent catalytic ability to tetracycline (TC) degradation in a wide pH range of 4-10 without any external energy input. More than 90% of TC (100 mL, 50 mg/L) could be degraded within 30 min by 10 mg of the nanocomposite in the presence of 0.2 mL of 30 wt% H 2 O 2 . Based on the experimental results, it was concluded that the Mg-N coordination between MgNCN and MgO in MgNCN/MgO nanocomposites activated H 2 O 2 to produce primary singlet oxygen ( 1 O 2 ) and minor hydroxyl radicals (·OH), responding for TC degradation. In addition, the degradation pathways of TC were deduced by determining the generated intermediates during the degradation process. This work provided a novel idea for designing transition-metal-free catalysts for nonradical activation of H 2 O 2 in the absence of external energy excitation.
研究领域:
环境科学
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催化化学
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DOI
PubMed
高影响因子
WATER RESEARCH
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2019
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IF 7.913
Wanjun Wang,Hanna Wang,Guiying Li,Taicheng An,Huijun Zhao,Po Keung Wong
The development of cost-effective water disinfection methods is highly desired to address the problems caused by outbreak of harmful microorganisms . Sulfate radical (•SO 4 − )-based advanced oxidation technology has attracted increasing attention. However, various catalysts or UV irradiation are usually used to activate persulfate (PS), which is high-cost and the recovery of nano-sized catalysts is also challenging. This work demonstrates a new method of catalyst-free activation of persulfate by visible light (VL) for bacterial inactivation. The 6-log of E. coli cells can be inactivated within 40 min and 7-log of E. coli cells could be inactivated within 120 min by the VL/PS system. The major responsive wavelength is 420 nm, and no heat activation of PS is found during VL irradiation. A synergistic effect with synergy factor of 51.2% is found when combining the VL irradiation with heating at 50 °C. The acidic pH is benefit for the VL/PS-triggered bacterial inactivation, while bicarbonate inhibits the E. coli inactivation at the range of 0.1–20 mg/L. Mechanism study indicates the main reactive species are •SO 4 − , •O 2 − and •OH, in which •SO 4 − plays the most important role. The bacterial inactivation process shows to begin from outer membrane to intracellular components. Subsequently, the antioxidant enzyme (i.e. SOD, CAT) is induced, followed by damaging to the genomic DNA leading to fatal death of the cells. In addition, the VL/PS system is also applicable for the inactivation of other pathogenic bacteria, including Staphylococcus aureus and Pseudomonas aeruginosa , showing universality for water disinfection applications. This work not only provides a new cost-effective disinfection method without a catalyst, but also sheds light on understanding the bacterial inactivation mechanism by •SO 4 − -based AOPs .
研究领域:
环境科学
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微生物学
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产品关联
DOI
PubMed
高影响因子
MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING
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2019
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IF 2.722
Xinbo Jing,Xueying Peng,Xiyin Sun,Wu Zhou,Wei Wang,Shufen Wang
In this study, a facile impregnation-calcination strategy was applied in order to synthesize Mo2C modified MoO3 (Mo2C/MoO3), which was then employed as catalyst for the photoreduction of Cr (VI) and photodegradation of methyl orange (MO) upon irradiation by visible light (λ > 400 nm). The apparent rate constant (k) of Mo2C/MoO3 for the MO photocatalyzed degradation reaction under visible-light irradiation was found to be 0.0171 min-1, which was 4.59 and 67.38 times higher than that of Pt/MoO3 and pristine MoO3, respectively. Study of the photocatalytic mechanism revealed that the •O2- species played a major role in MO degradation. Moreover, the addition of Mo2C enhanced the light response region of MoO3, and also promoted the photocatalytic activity of MoO3. This was due to the enhanced separation efficiency of photogenerated electron-hole pairs and broader photoresponse region. This work suggests a new use for the easily accessible Mo2C/MoO3 heterostructure and could facilitate the application of photocatalysts for wastewater treatment．
研究领域:
环境科学
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材料科学
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DOI
高影响因子
BIOCHEMICAL ENGINEERING JOURNAL
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2021
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IF 3.978
Xiao Li,Xiaomei Wu,Tao Yuan,Junrun Zhu,Yaling Yang
Nitrogen- and iodine-doped carbon dots (I-CDs) were synthesized as peroxidase mimics for the antifungal disinfection of Candida albicans ( C. albicans ). The prepared I-CDs samples exhibited peroxidase-like activity in the presence of exogenous H 2 O 2 . The peroxidase-like activities and antifungal effects of the I-CDs samples were enhanced by increasing their iodine content from 0.1599 g to 0.4796 g. The antifungal activity of the I-CDs (i.e., 2.72 mg/mL) against C. albicans reached > 90% in the presence of exogenous H 2 O 2 (0.5 mM) under visible light irradiation for 120 min. The in vitro experimental results showed the excellent photocatalytic antifungal activity of the designed system against C. albicans . It was theorized that this system promotes the formation of reactive oxygen species, including hydroxyl radicals (·OH), which can successfully inhibit the growth of C. albicans . The antifungal effect of the synergistic I-CDs/H 2 O 2 system on C. albicans could be attributed to the combined effects of its peroxidase-like and photocatalytic activities; the increased activities appeared to be closely related to the iodine content. The results of the present study are expected to broaden the biological applications of the I-CDs and elucidate the relationship between the iodine content and peroxidase-like enzymatic and antifungal activities of the I-CDs.
研究领域:
纳米技术
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生物催化
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抗菌化学
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材料科学
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产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2021
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IF 5.316
Lifen Wang,Yonggang Liu,Yinjun Lin,Yonghao Yu,Xueying Zhang,Ruiqin Zhang,Yunpu Zhai
In this study, an effective Ni-doped Cu 2 (OH) 3 F was synthesized by a simple one-step hydrothermal method to activate H 2 O 2 for degrading organic pollutants in water. The prepared (Cu 2−x Ni x ) 2 (OH) 3 F showed significant degradation performance for the degradation of RhB and TC. The characterization methods of XRD, XPS , TEM , SEM, FT-IR proved that Ni successfully replaced part of the Cu in Cu 2 (OH) 3 F site and provided more active sites for decomposition of H 2 O 2 through the synergistic effect of the bimetal . Besides, the photochemical properties of the prepared catalysts were analyzed by UV–vis, electrochemical impedance spectroscopy and transient photocurrent, which confirmed that the introduction of Ni narrowed the band gap of (Cu 2−x Ni x ) 2 (OH) 3 F and accelerated the separation of photogenerated electrons and hole pairs. Free radical capture experiments showed that •OH, h + , and •O 2 - all contributed to the reaction, and •OH was the main active substance. This research provides a photo-Fenton-like catalyst with simple synthesis, high performance and stable properties for future sewage treatment.
研究领域:
环境科学
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材料科学
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DOI
高影响因子
Nanoscale
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2021
·Vol. 13
·期 35
·14713-14722
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IF 7.79
Xiaoshan Fan,Lingjie Ke,Hongwei Cheng,Hu Chen,Zhiguo Li,Enyi Ye,Xian-Jun Loh,Yun-Long Wu,Gang Liu,Zibiao Li
Efficient drug delivery, multifunctional combined therapy and real-time diagnosis are the main hallmarks in the exploitation of precision nanomedicine. Herein, an anthracene-functionalized micelle containing a magnetic resonance imaging (MRI) contrast agent, upconversion nanoparticles (UCNPs) and the photosensitizer IR780 is designed to achieve sustained drug release and enhanced photothermal and photodynamic therapy. The polymer-coated hybrid micelle was achieved by crosslinking anthracene-dimer with UV light (λ > 300 nm), which is converted from near-infrared (NIR) irradiation upon UCNPs. Besides, the water-insoluble photosensitizer IR780 is introduced into the system to achieve efficient drug delivery and photothermal and photodynamic synergistic therapy. As a consequence of NIR-induced anthracene-dimer formation, the cross-linked nanocomposite shows sustained drug release, and the enhanced retention effect of IR780 could increase the photothermal conversion efficiency. Importantly, the incorporation of 2,2,6,6-tetramethyl-piperidineoxyl (TEMPO) as a nitroxide MRI contrast agent presents the potential for real-time diagnosis via nanotheranostics, and the fluorescence imaging of IR780 is applied to monitor drug distribution and metabolism. This strategy of sustained drug delivery by anthracene-dimer formation through the better penetration depth of NIR-II fluorescence provides an executable platform to achieve enhanced phototherapy in biomedical applications.
研究领域:
纳米医学
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生物医学工程
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诊疗学
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药物递送系统
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光疗
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2019
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IF 6.361
Jun Song,Jianyong Yu,Gang Sun,Yang Si,Bin Ding
Constructing a flexible inorganic membrane photocatalyst for efficient visible-light-driven water disinfection is highly desired but remains a great challenge. Herein, we fabricated a flexible and heterostructured silver/bismuth oxyiodide/titania (Ag/BiOI/TiO 2 ) nanofibrous membrane by combining the electrospinning technique with simple successive ionic layer adsorption and reaction (SILAR) and photodeposition process. In this ternary nanocomposite , ultrathin BiOI nanoplates were firmly anchored onto TiO 2 nanofibers , while Ag nanoparticles were uniformly decorated on the surface of both BiOI and TiO 2 . Benefiting from the large surface area, improved visible-light absorption, and the effective interfacial charge transfer induced by multi-heterojunctions, the resultant Ag/BiOI/TiO 2 membrane exhibited superior photocatalytic disinfection activity (7.5 log inactivation of E. coli within 1 h) under visible light illumination. Moreover, the plasmonic Z-scheme charge transfer mode was also proposed for Ag/BiOI/TiO 2 system according to the band structure and reactive species analysis. More significantly, the Ag/BiOI/TiO 2 membrane-based photoreactor could be facilely constructed for high-efficiency disinfection of high volume contaminated water, and the membrane still maintained good structural integrity and mechanical flexibility after utilization. This work may open up new avenues for designing and constructing flexible high-performance photocatalytic membranes for environmental applications.
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
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2020
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IF 5.774
Chun Tong,Liquan Jing,Minqiang He,Meng Xie,Wei Wei,Yuanguo Xu,Hui Xu,Huaming Li
Designing a green and efficient catalyst to effectively degrade antibiotics is still one of the hot topics of research. Firstly, 1D nanorod Fe 2 O 3 /NaNbO 3 composite was successfully prepared by the two steps strategy through hydrothermal combined calcination method. In addition, the photocatalytic activity of the samples was evaluated by the degradation of tetracycline (TC) under visible light irradiation. The test results show that the 5% Fe 2 O 3 /NaNbO 3 nanorod material exhibits superior degradation rate of TC (89.4% removal efficiency in 90 min), and shows 5.62 times than that of NaNbO 3 nanorods. Under UV–visible light irradiation, 5% Fe 2 O 3 /NaNbO 3 nanorod composite with H 2 O 2 solution can degrade 97.4% of TC in 60 min, which is 12.1 times greater to that of the pure NaNbO 3 nanorods. The outstanding degradation performance may be attributed to the introduction of Fe 2 O 3 nanoparticles, which can activate H 2 O 2 more efficiently and produce more free radicals to degrade pollutants. At the same time, the 5% Fe 2 O 3 /NaNbO 3 nanorod composite can also act as an activate persulfate (PS) and generate SO 4 − to efficiently degrade TC. In addition, the catalyst also showed good performance in degrading TC in the presence of different anions and cations. Plant growth experiment ( mung bean seeds ) results showed that the degradation products have obvious lower toxicity. This study provides new domain about the designing of a photo-Fenton catalyst having dual ion synergy (Fe 3+ /Fe 2+ and Nb 5+ /Nb 4+ ) and full spectrum response.
研究领域:
环境科学
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催化材料
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污染控制
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DOI
高影响因子
CELLULOSE
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2018
·Vol. 25
·期 10
·5687-5696
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IF 3.809
Liu Shaojie,Sun Tingting,Yang Desheng,Cao Meng,Liang Huazhe
Abstract Water-soluble polyacrylic acid was prepared by solution polymerization, and then partially acylated by SOCl 2 to give a random copolymer of poly(acrylic acid- co -acryloyl chloride) (P(AA- co -AC)). Through the reaction of acyl chloride groups in P(AA- co -AC) with hydroxyl groups in 4-hydroxy-2,2,6,6-tetramethyl-piperidinooxy (4-OH-TEMPO), the water-soluble TEMPO immobilized copolymer of poly(acrylic acid- co -2,2,6,6-tetramethylpiperidinyloxy-4-yl-acrylate) (P(AA- co -TA)) with different TEMPO loadings were prepared and characterized by Fourier transform infrared spectroscopy and conductometric titration. P(AA- co -TA) was used as a recoverable catalyst instead of free TEMPO for selective catalytic oxidation of cellulose in water. The carboxyl content of oxidized cellulose with P(AA- co -TA) as catalyst was up to 60% of the free TEMPO level. Furthermore, P(AA- co -TA) was easy to recycle by its pH-sensitivity and the activity did not decrease after 4 cycles. Graphical abstract
研究领域:
化学工程
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材料科学
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催化化学
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）