COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2022
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IF 5.518
Shangyuan Ni,Zhengrong Fu,Lin Li,Manying Ma,Yuelin Liu
Construction of heterojunction between semiconductors is considered an effective strategy for enhancing photocatalytic capability. Herein, this work prepared an abundant porous g-C 3 N 4 /TiO 2 photocatalyst , with the two-dimensional (2D) nanosheet g-C 3 N 4 and nanoparticle TiO 2 . The heterojunction both enhanced the ultraviolet (UV) light absorption ability, and inhibited the recombination of photogenerated electron-hole (h + ) pairs. As expected, the optimal 4 % g-C 3 N 4 /TiO 2 (g-C 3 N 4 :TiO 2 = 1:25) exhibited a prominent degradation efficiency of 96.53 % in the photocatalytic performance of tetracycline hydrochloride (TCH) under UV irradiation . The recycling of the heterojunction photocatalyst g-C 3 N 4 /TiO 2 remained stability and reusability. The main active species were·O 2- , h + and·OH, and the formation of internal electric field on the step-scheme (S-scheme) heterojunction interface accelerated the migration of photogenerated carriers. Moreover, several environmental factors on degradation such as dose, pH, and the initial concentration of TCH were investigated. This work could be spread to the conceive of other S-scheme heterojunction photocatalysts in application to different environmental demands.
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
Road Materials and Pavement Design
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2019
·
IF 1.98
Xuejuan Cao,Mei Deng,Boming Tang,Yongjie Ding,Xiaoyu Yang
Nitric oxide (NO) emitted from vehicle exhausts are associated with adverse health effects on the public. This study prepared a graphitic carbon nitride (g-C3N4)/TiO2 composite using melamine and titanium dioxide (TiO2) and then applied the composite on chip seal for the photocatalytic removal of NO. The g-C3N4/TiO2 composite was synthesised by an ultrasonic-assisted solid-phase synthetic method. The results of X-ray powder diffraction, Fourier-transform infrared spectroscopy, and a scanning electron microscope indicated that g-C3N4 and TiO2 were successfully synthesised and most of the sheet structures of g-C3N4 were attached by approximately spherical TiO2 particles. The UV–Vis and PL characterisation suggested that optical absorption range of TiO2 was broadened and the separation of electronic-holes was hindered, which contributed significantly to the enhancement of the visible-light photocatalytic activity. The loading capacity of 0.0092 kg/m2 g-C3N4/TiO2 composite on chip seal specimens had the highest NO removal efficiency of 31.41% within 30 min.
研究领域:
环境科学
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材料科学
✓ 已验证
DOI
高影响因子
ANALYST
·
2018
·Vol. 143
·期 20
·5030-5037
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IF 3.864
Qiong Wu,Fengxia Zhang,Huijuan Li,Zhihua Li,Qi Kang,Dazhong Shen
Herein, we report a ratiometric photoelectrochemical (PEC) immunosensor coupled with secondary antibodies–Co3O4 nanoparticle conjugates (Ab2–Co3O4 NPs) for signal amplification. The Ab1-g-C3N4@TiO2 NTs and BSA-g-C3N4@TiO2 NTs act as the sensing and reference photoelectrodes, where Ab1, BSA and TiO2 NTs are the capture antibodies, bovine serum albumin and TiO2 nanotube arrays, respectively. In the presence of target Ag, the sensing PEC photocurrent decreases due to the steric hindrance of Ab1 molecules, which increases the inner resistance of the photoelectrode. The signal-off response is enhanced further using Ab2–Co3O4 NP conjugates due to their steric hindrance effect and the consumption of electron donors by the Co3O4 NPs. Furthermore, the performance of the ratiometric PEC platform is tested using alpha-fetoprotein (AFP) as a model antigen. Under the optimal conditions, the concentration of AFP is detected in the range of 0.4 pg mL−1 to 40 ng mL−1 with a detection limit of 0.2 pg mL−1. This ratiometric strategy is beneficial to improve the reliability and anti-interference ability of PEC immunosensors.
研究领域:
生物医学工程
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分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CERAMICS INTERNATIONAL
·
2018
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IF 3.057
Xiang Lv,Tianhe Wang,Wei Jiang
We report a novel method to prepare translucent and stable Ag@AgCl/g-C 3 N 4 /TiO 2 ceramic films having strong photocatalytic activities and self-cleaning capabilities under light irradiation. Colloidal silica was used as an inorganic binder and P25 TiO 2 was added as a hydrophilicity enhancer without which a smooth coating was not achievable. Ag@AgCl of particle size around 30 nm, was synthesized by in-situ oxidation of nano-silver particles in porous g-C 3 N 4 /TiO 2 films. Optimal conditions for Ag@AgCl/g-C 3 N 4 /TiO 2 preparation in terms of strongest photocatalysis were established by tests on Rhodamine B degradation under visible and full spectral irradiations. A good adhesion strength of the porous films on glass substrate was achieved. Stability and reusability of the films were assessed by cycling tests. Possible photocatalytic mechanisms are proposed based on the basis of trapping experiments. Systematic characterization of the film suggests that the in-situ oxidation is an effective and practical method to produce nanoscale Ag@AgCl.
研究领域:
材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2018
·
IF 3.057
Minquan Sun,Shuling Shen,Zhujun Wu,Zhihong Tang,Jiaping Shen,Junhe Yang
A novel rice spike-like g-C 3 N 4 /TiO 2 nanowire heterojunctions are fabricated by hydrothermal treating Na 2 Ti 3 O 7 ultralong nanotubes in the presence of g-C 3 N 4 . The presence of g-C 3 N 4 promotes the hydrolysis of Na 2 Ti 3 O 7 ultralong nanotubes. The partially replaced O of TiO 2 by N from g-C 3 N 4 leads to the formation of a tight-binding interface between one dimensional TiO 2 and two dimensional g-C 3 N 4 , which is crucial for fast and effective transfer of photogenerated electrons in heterostructured photocatalysts . As a result, the g-C 3 N 4 /TiO 2 nanowire heterojunctions exhibit excellent visible-light photocatalytic activity. The kinetic constant (k) of g-C 3 N 4 /TiO 2 (0.024 min −1 ) for degradation of methylene blue under visible light irradiation is 1.85 and 4 times than that of pure g-C 3 N 4 and P25, respectively.
研究领域:
材料科学
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环境科学
✓ 已验证
DOI
高影响因子
NANO
·
2021
·
IF 1.556
Zongli Ren,Zhongwei Zhao,Zhao Yang,Bin Cheng,Xuan Yang
Constructing heterojunction photocatalyst is an effective method to enhance the separation of photogenerated electron and hole, which significantly improves ability of visible light response. In this study, calcination methods have been proposed to prepare highly efficient magnetic ternary photocatalyst g-C 3 N 4 /TiO 2 -MnFe 2 O 4 halloysite. It showed an enhanced photocatalytic degradation for dyes (crystal violet) and nonsteroidal anti-inflammatory drugs (acetaminophen) under vision light irradiation. Compared to pure g-C 3 N 4 , TiO 2 , MnFe 2 O 4 halloysite and binary g-C 3 N 4 -MnFe 2 O 4 halloysite, the optimized ternary g-C 3 N 4 /TiO 2 -MnFe 2 O 4 halloysite displayed enhanced photodegradation efficiency with 91.1% removal of crystal violet (10 ppm) in 90 min under visible light irradiation, the optimized ternary g-C 3 N 4 /TiO 2 -MnFe 2 O 4 halloysite composite showed significantly enhanced photocatalytic activity with more than 79.1% removal of acetaminophen (10 ppm) within 90 min under visible light. The photocatalytic mechanism was identified through the free radical quenching experiment. The heterojunction photocatalyst could be easily recovered by an extra magnetic field and reused several times without any obvious deterioration in catalytic activity. Besides, the ternary heterojunction also exhibited antibacterial ability against Escherichia coli . The superior photocatalytic performance of composite should be mainly attributed to both the improvement of light harvesting as well as the enhanced separation and transfer efficiency. It is expected that this novel ternary visible-light responding composite would be a promising candidate material for organic pollutants degradation and bacteria inactivation.
研究领域:
环境科学
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材料科学
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光催化技术
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微生物学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
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2017
·
IF 3.387
Ruirui Hao,Guohong Wang,Chuanjia Jiang,Hua Tang,Qingchuan Xu
Semiconductor-based photocatalysis is a promising method for degradation of environmental pollutants, but the activity of most widely used photocatalysts such as titania (TiO 2 ) is still unsatisfactory under visible light. Herein, we synthesized a highly efficient visible-light-responsive heterojunction catalysts based on graphitic carbon nitride (g-C 3 N 4 ) and TiO 2 . The g-C 3 N 4 /TiO 2 heterojunction composites with high specific surface area were prepared via in situ hydrothermal synthesis followed by calcination , using titanium tetrachloride (TiCl 4 ) and melamine as precursors. Interesting, HCl from the hydrolysis of TiCl 4 served as the proton source to acidify the melamine. The g-C 3 N 4 /TiO 2 heterojunction composites exhibited higher photocatalytic performance for decomposition of Rhodamine B (RhB) than pure g-C 3 N 4 or TiO 2 under visible light irradiation. The high activity can be ascribed to the high specific surface area (up to 115.6 m 2 g −1 ) of the g-C 3 N 4 /TiO 2 composites and a synergistic heterojunction structure between TiO 2 and g-C 3 N 4 . Moreover, the photocatalytic performances of the g-C 3 N 4 /TiO 2 composites rely on the content of melamine in the synthesis precursors: with an optimum melamine content (3 g for 0.5 mL of TiCl 4 ), the sample showed the highest photocatalytic performance, which is superior to pure TiO 2 and g-C 3 N 4 by a factor of 18.7 and 3.5, respectively. Active species trapping experiments revealed that superoxide radicals and photogenerated holes played crucial roles in the photocatalytic reactions. The results will provide new ideas for the smart design and development of g-C 3 N 4 -based highly active photocatalysts with ultrahigh specific surface area for environmental and energy applications.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
MICROCHEMICAL JOURNAL
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2017
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IF 3.034
Fujian Xu,Xiaoming Jiang,Jing Hu,Jinyi Zhang,Zhirong Zou,Xiandeng Hou,Hongjian Yan
Nano g-C 3 N 4 /TiO 2 composite was synthetized and utilized as a novel photocatalyst for enhanced photochemical vapor generation for sample introduction to atomic fluorescence spectrometry . High reduction efficiency for Se (VI) was obtained to facilitate its ultrasensitive determination by atomic fluorescence spectrometry, with a limit of detection of 0.08 ng mL − 1 . The photocatalytic mechanism of this composite was also discussed and demonstrated its highly efficient photocatalytic capacity and promissing applications in trace selenium (VI) determination and extraction.
研究领域:
分析化学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2023
·Vol. 30
·期 19
·55044-55056
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IF 5.8
Bi Renke,Liu Jialong,Zhou Chutong,Shen Yijie,Liu Zhe,Wang Zhiyu
The construction of heterojunctions between semiconductors is a preferred route to improve overall photocatalytic activity. In this work, a facile and feasible method was innovatively developed to one-step prepare g-C 3 N 4 /TiO 2 heterojunctions via an absorption-calcination process using nitrogen and titanium precursors directly. This method can effectively avoid interfacial defects and establish a tight interfacial connection between g-C 3 N 4 and TiO 2 . The resultant g-C 3 N 4 /TiO 2 composites exhibited prominent photodegradation efficiency for tetracycline hydrochloride (TC-HCl) under visible light and simulated-sunlight irradiation. The optimal g-C 3 N 4 /TiO 2 composite (urea content of 4 g) showed the highest photocatalytic efficiency, which can degrade 90.1% TC-HCl under simulated-sunlight irradiation within 30 min, achieving 3.9 and 2 times increases compared to pure g-C 3 N 4 and TiO 2 , respectively. Besides, photodegradation pathways based on the role of active species ·O 2 − and ·OH were identified, indicating that a direct Z-scheme heterojunction was formed over the g-C 3 N 4 /TiO 2 photocatalyst. The enhanced photocatalytic performance can be attributed to the close-knit interface contact and the formation of Z-scheme heterojunction between g-C 3 N 4 and TiO 2 , which can accelerate the photo-induced charge carrier separation, broaden the spectra absorption range, and retain a higher redox potential. This one-step synthesis method may provide a new strategy for the construction of Z-scheme heterojunction photocatalysts consisting of g-C 3 N 4 and TiO 2 for environmental remediation and solar energy utilization.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2018
·Vol. 25
·期 19
·19122-19133
·
IF 2.8
Ren Bin,Wang Tiecheng,Qu Guangzhou,Deng Fang,Liang Dongli,Yang Wenli,Liu Meishan
As a highly active photocatalyst, g-C 3 N 4 /TiO 2 heterojunction nanocomposites were in situ synthesized by simple ultrasonic mixing and calcination by using TiO 2 and melamine as precursors. The morphology and structure of the prepared photocatalysts were characterized by field emission scanning electron microscopy, transmission electron microscopy, X-ray diffraction, Fourier-transform infrared spectroscopy, UV-Vis diffuse reflectance spectroscopy, and X-ray photoelectron spectroscopy. The photocatalytic activities of g-C 3 N 4 /TiO 2 nanocomposites to degrade Orange II (AO7) under visible light irradiation were evaluated. Results showed that the photocatalytic rate of the prepared g-C 3 N 4 /TiO 2 photocatalyst to degrade AO7 was about three times than that of pristine TiO 2 and g-C 3 N 4 . The g-C 3 N 4 /TiO 2 composite with a ratio of 1:4 had the highest degradation efficiency for AO7 solution. Its degradation efficiency under acidic conditions was significantly higher than that under alkaline conditions. The enhancement of photocatalytic activity can be attributed to the formation of heterojunctions between g-C 3 N 4 and TiO 2 , which leads to rapid charge transfer and the efficient separation of photogenerated electron-hole pairs. The recycling experiment indicated that the photocatalyst of g-C 3 N 4 /TiO 2 nanocomposites still maintained good photochemical stability and recyclability after five cycles; this finding was important for its practical applications. A series of free radical trapping experiments showed that •O 2 − played a crucial role in the degradation of AO7.
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研究领域:
材料科学
·
环境科学
·
化学工程
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2021
·
IF 6.165
Yi Huang,Gen Zhu,Kun Zou,Fei Tian,Thakur Prasad Yadav,Hui Xu,Guohai Yang,Haitao Li,Lulu Qu
Membrane fouling has been a major challenge in the practical application of membrane technology for wastewater treatment and purification. In this study, a reusable membrane composed of g-C 3 N 4 @TiO 2 -nanowires modified graphene oxide (GO/CN@TNWs) was successfully fabricated through electrostatic interactions and a vacuum filtration-assisted self-assembly process. The as-fabricated membrane possessed higher photocatalytic activity than the pure TNWs under simulated solar light exposure, attributing to the introduction of GO with high absorption and carrier mobility, and the synergistic effects of TNWs and CN. Furthermore, the π-π stacking interactions between GO and organic pollutant molecules contribute to the excellent enrichment efficiency of GO/CN@TNWs membrane (98.77%) toward tetracycline hydrochloride (TCH). Room-temperature ESR studies indicate that the GO/CN@TNWs membrane can generate more superoxide radical, hydroxyl radical and hole species for photocatalytic degradation. Therefore, the GO/CN@TNWs membrane may be used for TCH removal from waste water and the excellent solar-light-driven photocatalytic performance endows GO/CN@TNWs membrane absorbents with recycling abilities for the realization of large-scale wastewater purification.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2024
·
IF 4.9
Yunfei Xu,Ying Li,Yongjian Wei,Haiou Liang,Tong Xu,Yinghui Sun,Jie Bai
Photothermal synergistic catalysis of Suzuki-Miyaura coupling reaction not only utilizes the solar energy efficiently, but also reduces the energy consumption. It is a green organic synthesis method for constructing C–C bonds, which has a wide application. In this work, we constructed a PdO/g-C 3 N 4 /TiO 2 bilayer tubular structure material with a heterojunction structure by a simple and effective method. The catalyst exhibited efficient photothermal synergistic catalytic performance in Suzuki coupling reaction under visible light irradiation. The influence of the catalyst’s structure, morphology, composition, and photothermal response on the Suzuki coupling reaction were discussed based on a series of characterizations and activity test of the catalyst. The results showed that the PdO/g-C 3 N 4 /TiO 2 catalyst contained an effective g-C 3 N 4 /TiO 2 heterojunction structure. Under visible illumination, the differences in interfacial charge concentration and electron affinity between these two different types of semiconductors lead to charge rearrangement and transfer, which greatly improves the carrier separation efficiency. Meanwhile, palladium metal exhibits excellent electron deposition effects, both as an active metal center for SMC reactions and as an electron acceptor for facilitating photoelectron transfer. Electron-rich palladium atoms play an important role in C–C bond formation reactions, improving catalytic efficiency. The PdO/g-C 3 N 4 /TiO 2 catalyst has excellent catalytic activity and can catalyze the SMC reaction under visible light and at 0 ℃, the yield reached 85.6%, which is comparable to the activity of thermal catalysis for 15 minutes. Furthermore, after five cycles, the PdO/g-C 3 N 4 /TiO 2 catalyst still maintained an 83.1% yield, demonstrating excellent cycle stability. This article offers an effective strategy for preparing heterojunction catalyst with visible light response for photothermal reaction and presents the potential of these catalysts as a way to improve the efficiency and sustainability of Suzuki coupling reactions.
研究领域:
材料科学
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催化化学
·
有机合成
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）