RSC Advances
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2014
·Vol. 4
·期 75
·40019-40028
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IF 3.708
Wei Zhong,Ying Yu,Chun Du,Wei Li,Yinzhen Wang,Guannan He,Yuandong Xie,Qinyu He
Buoyant photocatalysts which are able to remove organic pollutants under all lighting and weather conditions are in demand for the treatment of large volumes of organic wastewater. Buoyant carbon and nitrogen co-doped TiO2/polytetrafluoroethylene (NCT/PTFE) flakes which meet these requirements were prepared by the high-energy ball-milling of NCT powder and PTFE. The physicochemical properties of the as-prepared composite flakes were evaluated by X-ray diffraction (XRD), scanning electron microscopy (SEM), ultraviolet–visible diffuse reflection spectroscopy (UV-vis DRS), Brunauer–Emmett–Teller (BET) surface area determination, and X-ray photoelectron spectroscopy (XPS), as well as electrical conductivity and density measurements. The density of the composite flakes was 0.93 g cm−3, slightly lower than that of water, rendering them buoyant. And the used-and- regenerated (by UV-vis irradiation for 8 h) flakes are also buoyant. Adsorption in the dark and photodegradation experiments indicated that the as-prepared flakes have high dark adsorption and high photocatalytic properties. The 6 h photodegradation ratio of methylene orange (20 mg L−1, 100 mL, as a model dye) is 96.6%, and a close degradation ratio of 97% can be obtained by three-cycle dark adsorption with minor stirring (1 cycle includes 8 h dark adsorption followed by 8 h regeneration by UV-vis irradiation per cycle). The high adsorption and good photocatalytic properties can be mainly attributed to the large BET surface area resulting from the small NCT particle size. The as-prepared flakes have the potential for use in organic pollutant adsorption at any time and can be regenerated through light irradiation when sunlight is available. This kind of environmental protection material has great practical significance due to its low cost, simple preparation, thermal durability, highly efficient organic pollutant removal, large-volume treatment capacity, recyclability, and the possibility of working at any time.
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
GREEN CHEMISTRY
·
2021
·Vol. 23
·期 24
·10039-10049
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IF 10.182
Yingying Cao,Dandan Chen,Ye Meng,Shunmugavel Saravanamurugan,Hu Li
Chemocatalytic production of lactic acid from biomass feedstock is an alternative route with high potential, but with the prerequisites of long reaction time, high temperature, and/or a tailored catalyst. In this work, an N-TiO2 photothermal catalyst prepared by a simple sol–gel method using urea as a nitrogen and carbon source could catalyse a variety of biomass sugars to quantitatively produce lactic acid (up to 98.9% yield) in water under visible light and at a low temperature of 60 °C in a time as short as 30 min. N-TiO2 provides a suitable valence band position (2.51 eV) for the photo-oxidation reaction, with more active species being formed on the catalyst surface (e.g., h+, e−, ˙OH and ˙O2) and a light-induced heating effect caused by the carbon photothermal layer, which can effectively activate carbohydrates to undergo a cascade reaction process. Theoretical calculations show that the charge of N-TiO2 is highly separated, in which the N element acts as an electron trap and is enriched with plenty of electrons, leading to effective isolation of holes and electrons. In addition, the N-TiO2 catalyst exhibits good reusability and can be recycled with little loss of activity. The developed N and C-enhanced photothermal synergistic protocol opens up an avenue for producing organic acids from renewable biomass resources under mild conditions.
研究领域:
催化化学
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可再生资源利用
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环境科学
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DOI
高影响因子
APPLIED SURFACE SCIENCE
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2022
·
IF 7.392
Taiguang Li,Mingyong Wang,Qingzheng Hou,Yaqi Hou,Kai Xuan,Yongmei Hao
One kind of novel magnetically separable graphene-based titanium dioxide photocatalytic nano-adsorbents (GO-FSNTs) were prepared for the adsorption-photodegradation of phenanthrene under visible light. The GO-FSNTs displayed the high adsorption-photodegradation efficiency and 10 mg of 0.6% GO-FSNT (wt%) can remove 94.9% of phenanthrene within 4 h. The introduction of a small amount of GO enables 0.6% GO-FSNT to selectively adsorb phenanthrene through the π-π interaction, reduce the light-shielding effect and improve separation of photogenerated carriers effectively. Meanwhile, the N-TiO 2 shell is occupied by adsorbed water molecules which can spontaneously repair lattice oxygen. Furthermore, the more hydrophilic surface of 0.6% GO-FSNT is formed by increased photoinduced hydroxyl groups under visible light during photodegradation. The photoinduced hydroxyl groups can further generate OH and improve photocatalytic activity. The degradation pathway of phenanthrene was proposed based on intermediates analysis and density functional theory calculations. This work helps to reveal the relationship between the adsorption-photodegradation and the photoinduced hydrophilicity.
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
SENSORS AND ACTUATORS B-CHEMICAL
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2023
·
IF 8.4
Wei Wu,Jingyu Long,Yuanjun Guo,Xiaotao Zu,Sean Li,Xia Xiang
A surface acoustic wave (SAW) H 2 S gas sensor based on CuO-TiO 2 p-n heterojunction film was designed and fabricated. The sensor exhibits high sensitivity to H 2 S due to the significant current response of CuO-TiO 2 film to H 2 S gas and the appropriate work point of SAW sensor based on CuO-TiO 2 composite film. The linearity change for sensor frequency shift is strongly associated with the location of work point when the H 2 S concentration increases from 1 to 300 ppm. In addition, the porosity of CuO-TiO 2 film is beneficial to the efficient adsorption for H 2 S, leading to the higher frequency shift of the sensor. The SAW sensor also shows good selectivity and stability to H 2 S with stable frequency shift under different humidity levels.
研究领域:
材料科学
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传感器技术
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气体检测
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产品关联
DOI
高影响因子
Journal of Energy Chemistry
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2026
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IF 15.6
Xingyang Wu,Yucui Xiang,Liyong Gan,Shuaijun Wang,Zhongkai Hao,Guo Qin Xu,John Hon Kay Yip
Selective solar-driven conversion of CO 2 into C 2 hydrocarbons under aqueous conditions is a promising route toward carbon neutrality. However, C 2 selectivity in water is severely constrained because the intrinsically slow C–C coupling requires sustained electron flux to build up coupling-relevant intermediates. This flux is readily depleted by the competing hydrogen evolution reaction and rapid carrier recombination. Here, we construct an in situ S-scheme heterojunction of CuO islands on two-dimensional (2D) N-TiO 2 (CuO/N-TiO 2 ) via a one-pot solvothermal strategy. The chemically anchored CuO islands on 2D N-TiO 2 nanosheets create a compact, coherent interface that facilitates interfacial charge transfer. Compared with an ex situ assembled counterpart, the in situ heterojunction shows more efficient S-scheme charge separation. In situ characterizations and theoretical calculations reveal that dynamically redox-cycling Cu 2+ /Cu + sites are beneficial for C 2 H 4 formation, with Cu + sites favoring *CO retention and Cu 2+ sites being more favorable for the subsequent asymmetric *CO–*CHO coupling step. Consequently, the as-prepared catalyst delivers 17.5 μmol g −1 ethylene in 4 h with 94.6% selectivity and robust cycling stability. This work establishes an in situ S-scheme heterojunction with oxide islands anchored on 2D nanosheets that integrates charge management with dynamic active sites for selective aqueous CO 2 -to-C 2 H 4 photoreduction. An in situ grown CuO-islands/2D N-TiO 2 S-scheme heterojunction promotes charge separation for aqueous CO 2 -to-C 2 H 4 photoreduction without sacrificial agents. The dynamic Cu 2+ /Cu + active sites favor *CO formation, asymmetric *CO–*CHO coupling, and ethylene selectivity. Download: Download high-res image (161KB) Download: Download full-size image
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DOI
高影响因子
AQUATIC TOXICOLOGY
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2024
·
IF 4.1
Haiyue Chen,Yingjia Wang,Hongwu Liang
Dibutyl phthalate (DBP) is a commonly used plasticizer that is frequently detected in water samples due to its widespread use. Titanium dioxide nanoparticles (n-TiO 2 ) have been found to enhance the harmful effects of organic contaminants by increasing their bioavailability in aquatic environments. However, the combined toxic effects of DBP and n-TiO 2 on aquatic organisms remain unclear. This study aimed to investigate the neurotoxicity of DBP and n-TiO 2 synergistic exposure during the early life stage of zebrafish. The results of the study revealed that co-exposure of DBP and n-TiO 2 led to an increase in deformities and a significant reduction in the active duration of zebrafish larvae. Furthermore, the co-exposure of DBP and n-TiO 2 resulted in elevated levels of oxidative stress and altered gene expression related to neurodevelopment and apoptosis. Notably, n-TiO 2 exacerbated the oxidative damage and apoptosis induced by DBP alone exposure. Additionally, co-exposure of the 1.0 mg/L DBP and n-TiO 2 significantly affected the expression of genes associated with neurodevelopment. Moreover, disturbances in amino acid metabolism and interference with lipid metabolism were observed as a result of DBP and n-TiO 2 co-exposure. In general, n-TiO 2 aggravated the neurotoxicity of DBP in the early life stage of zebrafish by increasing oxidative stress, apoptosis, and disrupting amino acid synthesis and lipid metabolism. Therefore, it is essential to consider the potential risks caused by DBP and nanomaterials co-existence in the aquatic environment.
研究领域:
环境毒理学
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水生生物学
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分子生物学
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神经科学
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产品关联
DOI
PubMed
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
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2026
·
IF 8.3
Dongxue Yu,Yimin Tang,Ziqi Liu,Lihui Hu,Xin Jiang,Bing Zhao,Libin Yang
Developing new-type semiconductor surface-enhanced Raman scattering (SERS) platform with synchronous enhancement of sensitivity and stability is an effective strategy for achieving ultra-sensitive detection of emerging pollutants in various pollution scenarios. In this work, a new g-C 3 N 4-x /N-doped TiO 2-x (g-C 3 N 4-x /N-TiO 2-x ) heterojunction SERS matrix was purposefully developed by a combined strategy of interface engineering and defect engineering. During the formation of heterojunction, “N-bidirectional migration” between two monomers can be achieved (that is, N vacancies and N doping can be generated simultaneously), which achieves a synchronous modulation of the atomic and electronic structures of the heterojunction. This endows g-C 3 N 4-x /N-TiO 2-x with excellent interfacial performance, abundant defect states, as well as ultra-high stability. The enhancement factor of the SERS matrix is as high as 10 9 . Theoretical calculations and experiments reveal the contribution of charge transfer (CT) mechanism to the SERS enhancement. The high-efficiency carrier separation induced by the strong interface coupling effect and the multi-channel CTs mediated by multiple defect states (vacancy defects and doping defects) are jointly responsible for the observed huge SERS enhancement. Benefiting from its high SERS sensitivity (selectivity) and excellent stability, g-C 3 N 4-x /N-TiO 2-x can be applied for ultrasensitive detection of antibiotic pollutants in multiple scenarios, including animal-derived foods such as milk, sour milk and beef, as well as natural water systems such as lake water and seawater. The detection limit of several typical antibiotic residues (enoxacin, ciprofloxacin, sulfamethoxazole and florfenicol) is as low as 1 × 10 −11 mol/L.
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DOI
高影响因子
ACS Applied Nano Materials
·
2023
·
IF 5.9
Zhitong Jia,Songyuan Sun,Ao Li,Huigui Wu,Guoqiang Qin,Tong Liu,Pengpeng Lv,Jingbo Chen
Titanium dioxide (TiO2) is a promising anode material for lithium-ion batteries with the characteristics of highly stable structure and excellent safety, while the application is constrained by its inferior electrical conductivity and sluggish lithium-ion diffusion kinetics. Herein, H2Ti4O9 was prepared as a precursor, and it was wrapped with polyvinylpyrrolidone (PVP) as the nitrogen and carbon sources. Then, the N-doped carbon-filled TiO2 nanocrystals (N-TiO2/C), which had a unique dragon fruit structure with TiO2 nanocrystals acting as seeds and carbon acting as the flesh, were successfully prepared from PVP-coated H2Ti4O9 by one-step heat treatment. It is noteworthy that four modification methods, including carbon filling, nanosizing, nitrogen doping, and morphological designing, are all accomplished simultaneously during this process. The N-TiO2/C composite exhibits an outstanding stable capacity of 444.6 mAh g–1 after 600 cycles at 1 A g–1, and it possesses a reversible capacity of 146.7 mAh g–1 at 5 A g–1. The superior electrochemical capacity can be attributed to the distinctive dragon fruit structure along with nitrogen doping and carbon filling. The ingenious modification strategy can extend to the investigation on the other oxide anode materials.
研究领域:
材料科学
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电化学
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能源存储
·
纳米技术
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DOI
高影响因子