APPLIED SURFACE SCIENCE
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2019
·
IF 5.155
Xiuquan Xu,Songmei Wang,Xiaofeng Yu,Jila Dawa,Dongliang Gui,Ronghui Tang
Photocatalytic inactivation has been proved to be an effective strategy for controlling biohazards. Herein, the novel Ag deposited phosphorus and sulfur co-doped g-C 3 N 4 (PSCN) composites with different Ag content were constructed via a facile calcination combining with biogenic-reduction method for inactivating Escherichia coli ( E. coli ). The detailed characterization results indicated that P and S elements were successfully co-doped into g-C 3 N 4 (CN) lattice and Ag nanoparticles (NPs) were evenly deposited on the surface of PSCN with diameter range of 4–20 nm. The Ag/PSCN at depositing amount of 4 wt% (Ag/PSCN-4) achieved the strongest photocatalytic inactivation along with excellent stability, which could completely inactivate 7.0 log cells of E. coli within 60 min of visible light irradiation. This improved bactericidal performance was mainly attributed to the synergistic effects of P-S co-doped together with Ag deposition, which resulted in the increased visible light utilization, the improved separation and transfer efficiency of photo-induced charge carriers. Moreover, active species trapping experiments revealed that the generated superoxide radicals ( O 2 − ) and holes (h + ) played the significant roles in photocatalytic inactivation process. Our present work presented a promising and environmentally friendly strategy to enhance the photocatalytic capacities of CN based composites for pathogens inactivation.
研究领域:
环境科学
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微生物学
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材料科学
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DOI
高影响因子
ENVIRONMENTAL RESEARCH
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2019
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IF 5.026
Qian Lei,Junjian Zheng,Jinxing Ma,Xueye Wang,Zhichao Wu,Zhiwei Wang
An electrochemical dynamic membrane filtration (EDMF) system for simultaneous solid-liquid separation (also protecting electrodes against fouling) and sewage disinfection was developed. At a low voltage of 2.5 V, efficient disinfection performance was achieved in the EDMF, with ~100% log removal efficiency (no detectable bacteria in the effluent). Results also demonstrated that the EDMF system, operated at membrane flux of 100 L/(m 2 h), could maintain long-lasting bacterial disinfection efficiency of real wastewater (~100% log removal) in continuous flow tests. Transmembrane pressure (TMP) increased from 0.8 kPa to 22 kPa within 80 d (one operation cycle), and cleaning of EDMF could effectively restore TMP and biocidal behaviors for subsequent filtration cycles. In contrast, without dynamic membrane, the disinfection efficiency was decreased from initial ~100% log removal (with no detectable live bacteria) to ~44.4% log removal within 7 d. Reactive oxygen species (ROS)-mediated oxidation was responsible for bacteria disinfection in the EDMF, and HO• and H 2 O 2 generated in this system played a dominant role, causing damage to cell membranes and K + leakage from cytosol. Moreover, catalase and superoxide dismutase for intracellular ROS attenuation were inhibited, resulting in the increase of intracellular oxidative stress and thus high-efficient disinfection. These results highlight the potential of EDMF system to be used for wastewater treatment and disinfection.
研究领域:
环境工程
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水处理
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电化学
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膜技术
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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
Xiaohui Wu,Leitao Cao,Jun Song,Yang Si,Jianyong Yu,Bin Ding
TiO 2 -based fibrous membranes as plasmonic heterojunction photocatalysts would hold great promise in the field of water disinfection , however, it still existed a great challenge to design and construct such materials. Here, we presented the fabrication of continuous, hierarchical, and easy-to-recycle flexible Ag 2 C 2 O 4 /TiO 2 heterostructured nanofibrous membranes (NMs) that were composed of thorn-like nanofibers through electrospinning technique followed by successive ionic layer adsorption and reaction (SILAR) process. Ag 2 C 2 O 4 nanoplates were firmly anchored on the surface of TiO 2 and the obtained Ag 2 C 2 O 4 /TiO 2 heterojunction photocatalysts underwent a silent-to-active transition of visible-light response under light irradiation due to the surface plasmon resonance (SPR) effect of Ag nanoparticles derived from Ag 2 C 2 O 4 , forming a new plasmonic heterojunction photocatalyst. By virtue of the hierarchical structure, enhanced visible light absorption and efficient charge carriers separation, Ag 2 C 2 O 4 /TiO 2 NMs possessed high bactericidal efficiency of >99.999% within 30 min, strong reactive oxygen species (ROS) producing capability (1510 μg g −1 and 659 μg g −1 for superoxide radicals and hydroxyl radicals , respectively), and good reusability. This work may offer new insights into the design of antibacterial materials for pathogenic microorganism-contaminated water purification .
研究领域:
材料科学
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环境科学
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微生物学
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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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DOI
PubMed
高影响因子
WATER RESEARCH
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2019
·
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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DOI
PubMed
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
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2023
·Vol. 34
·期 5
·1-12
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IF 2.8
Wang Ze-Hong,Jia Yun-Ning,Wu Xiang-Feng,Song Meng-Chen,Ma Xiao-Ye,Wang Hui,Zhang Xue-Feng
Semiconductor photocatalysis is a promising method to solve the problem of antibiotic pollution in water. A series of Bi 2 SiO 5 /BiVO 4 composite photocatalysts for tetracycline and levofloxacin degradation are prepared by a two-step hydrothermal method. Analysis results show that the as-prepared Bi 2 SiO 5 /BiVO 4 (2:3) hybrid exhibits better photocatalytic activity than pure samples under visible light illumination. The photocatalytic degradation efficiency of the as-prepared composite shows the maximum of 72.2% within 120 min for tetracycline, which is higher than 43.5% of pure Bi 2 SiO 5 and 67.2% of pure BiVO 4 , respectively. Furthermore, it is 80.3% within 120 min for levofloxacin, which is higher than 7.6% of pure Bi 2 SiO 5 and 69.7% of pure BiVO 4 , respectively. The formation of n–n isotype heterojunction at the interface of Bi 2 SiO 5 and BiVO 4 in the as-prepared composites causes to the improvement of the transport rate and separation efficiency of the photogenerated electron and hole pairs. In addition, the holes play a dominant role in the photocatalytic degradation process. This work will provide a reference for the study of visible light driven photocatalysts to solve antibiotics pollution in water.
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
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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DOI
高影响因子
CHINESE JOURNAL OF CATALYSIS
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2018
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IF 3.525
Junxiu Wang,Zhenzong Zhang,Xi Wang,Yi Shen,Yongfu Guo,Po Keung Wong,Renbi Bai
A novel p-n heterostructure photocatalyst m-Bi 2 O 4 /BiOCl was successfully synthetized through a facile ion-etching method. Via adjusting the added volume of HCl solution, a series of different ratios of composite photocatalysts were obtained. The as-prepared samples of physical, chemical and optical characteristics were examined by X-ray diffraction, scanning electron microscope, transmission electron microscope, energy dispersive X-ray spectroscopy, selected-area electron diffraction, Fourier transform infrared absorption, Raman microscope, N 2 adsorption-desorption, X-ray photoelectron spectroscopy and UV-vis spectrum technologies. The photocatalysts showed high degradation rate and complete mineralization ability for methyl orange and tetracycline solution under visible light. The reaction rate constant of m-Bi 2 O 4 /BiOCl for methyl orange was 52.28 times higher than that of BiOCl. The characterization presented a good stability of materials. Furthermore, the photocurrent response test certified that the heterostructure effectively accelerated the separation and migration of photo-generated carries. The scavenger experiments evidenced that hole (h + ) and superoxide radical (•O 2 — ) were the primary active radicals. A possible photocatalytic mechanism was proposed. This work provided an alternative photocatalyst applied to water environmental remediation.
研究领域:
材料科学
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环境科学
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2022
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IF 16.744
Huiqin Ma,Weiyi Yang,Shuang Gao,Wanrong Geng,Yunli Lu,Chunliang Zhou,Jian Ku Shang,Tuo Shi,Qi Li
The internal polarizations of polar photocatalysts could be enhanced through unit cell structure modulations to improve their photocatalytic performances. In this work, a simple, robust and low-cost NaOH etching process is developed to treat ultrathin Bi 2 WO 6 nanosheets after their creation, resulting in a higher degree of polyhedron distortion (∼141 %) and an enhanced piezoelectricity (∼260 % the maximum effective piezoelectric coefficient d 33 ). Compared with pristine ultrathin Bi 2 WO 6 nanosheets, these etched samples demonstrate an improved charge carrier separation and transfer behavior due to their enhanced internal polarization with the assistance of richer oxygen vacancies, which largely enhance their piezocatalysis (∼4.6 times), photocatalysis (∼14.3 times) and especially coupled photopiezocatalysis (∼33.9 times) performances as demonstrated in their sulfamethoxazole (SMX) degradation performances. ·O 2 – , 1 O 2 and h + are proven to be main reactive oxygen species (ROSs) during their photopiezocatalytic process and they could also work well in the real water matrix.
研究领域:
材料科学
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环境科学
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催化化学
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DOI
高影响因子
Small
·
2017
·Vol. 13
·期 31
·1701354
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IF 8.643
Ning Zhang,Xiyu Li,Yifei Liu,Ran Long,Mengqiao Li,Shuangming Chen,Zeming Qi,Chengming Wang,Li Song,Jun Jiang,Yujie Xiong
Adsorption and activation of molecules on a surface holds the key to heterogeneous catalysis toward aerobic oxidative reactions. To achieve high catalytic activities, a catalyst surface should be rationally tailored to interact with both organic substrates and oxygen molecules. Here, a facile bottom-up approach to defective tungsten oxide hydrate (WO 3 ·H 2 O) nanosheets that contain both surface defects and lattice water is reported. The defective WO 3 ·H 2 O nanosheets exhibit excellent catalytic activity for aerobic coupling of amines to imines. The investigation indicates that the oxygen vacancies derived from surface defects supply coordinatively unsaturated sites to adsorb and activate oxygen molecules, producing superoxide radicals. More importantly, the Brønsted acid sites from lattice water can contribute to enhancing the adsorption and activation of alkaline amine molecules. The synergistic effect of oxygen vacancies and Brønsted acid sites eventually boosts the catalytic activity, which achieves a kinetic rate constant of 0.455 h −1 and a turnover frequency of 0.85 h −1 at 2 h, with the activation energy reduced to ≈35 kJ mol −1 . This work provides a different angle for metal oxide catalyst design by maneuvering subtle structural features, and highlights the importance of synergistic effects to heterogeneous catalysts.
研究领域:
催化化学
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材料科学
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表面化学
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DOI
PubMed
高影响因子
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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高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2018
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IF 6.578
Weicheng Fu,Xueye Wang,Junjian Zheng,Mingxian Liu,Zhiwei Wang
Membrane fouling remains as a critical issue limiting the widespread applications of membrane-based technologies for water and wastewater treatment . In this work, an electrochemical ceramic membrane reactor (ECMR), in which ceramic membrane with built-in Ti mesh acted as cathode/filter and Ti/SnO 2 -Sb-Ce as anodes, was developed for mitigating membrane fouling during wastewater treatment. Linear sweep voltammetry (LSV) and electrochemical impedance spectroscopy (EIS) of Ti/SnO 2 -Sb-Ce electrode demonstrated favorable electrochemical properties . Filtration tests with influent wastewater containing 50 mg/L sodium alginate (SA) showed that TMP increase rate for the ECMR was decreased by 23.9–72.7% compared to the control, dependent on the exertion modes of electric field in this reactor. It was found that all the oxidants contributed to the enhanced antifouling performance of the ECMR due to in-situ membrane cleaning effects while the hydrogen peroxide and active chlorine (Cl T ) played a more important role compared to superoxide anions and hydroxyl radicals. SA was oxidized to a smaller size after reacting with reactive oxygen species (ROS) and Cl T , benefiting the mitigation of membrane fouling in ECMR.
研究领域:
环境科学
·
污水处理
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DOI
高影响因子
危险品化学品经营许可证（带存储）