APPLIED CATALYSIS B-ENVIRONMENTAL
·
2020
·
IF 16.683
Yanxian Geng,Dongyun Chen,Najun Li,Qingfeng Xu,Hua Li,Jinghui He,Jianmei Lu
Heterojunctions have attracted considerable attention for efficiently utilizing solar energy and improving conversion efficiency during pollutant degradation. Herein, carbon nitride and hematite (α-Fe 2 O 3 ) are used to prepare a Z-scheme 2D/2D α-Fe 2 O 3 /g-C 3 N 4 heterojunction using an impregnation-hydrothermal method. The unique 2D/2D structure has a high interfacial area and widely-dispersed active sites. The energy band structure of the Z-scheme heterojunction leads to broad visible-light absorption and promotes charge transfer. Optimizing the content of the α-Fe 2 O 3 precursor in composite leads to a maximum efficiency of 60.8% for the removal of 600 ppb of NO , which is approximately 1.78 times that of g-C 3 N 4 (34.2%). The photocatalytic performance is greatly promoted because of the formation of the heterojunction and the strong interfacial action between g-C 3 N 4 nanosheets and α-Fe 2 O 3 nanoplates. Cycling experiments verify that the α-Fe 2 O 3 /g-C 3 N 4 heterojunction has good stability and reusability. The α-Fe 2 O 3 /g-C 3 N 4 heterojunction therefore has great potential in sustainable and efficient pollutant degradation.
研究领域:
环境催化
·
材料科学
·
物理化学
·
纳米科技
·
光化学
✓ 已验证
DOI
高影响因子
KINETICS AND CATALYSIS
·
2025
·
IF 1.4
Jiang Xin,Zeng Zhenxing
Interfacing two semiconductors for heterojuctions construction has been considered as an effective way to facilitate electron-hole separation, thus improving the photocatalytic activity. In this paper, PCN-224/g-C 3 N 4 heterojunction was constructed by PCN-224 and g-C 3 N 4 using a solvothermal method. Transmission electron microscopy (TEM) images reveal a well-matched, smooth interface between PCN-224 and g-C 3 N 4 , demonstrating the successful formation of a tight junction. Photoelectric performance tests confirm that the heterojunction significantly enhances the light absorption capability within the visible range and improves the efficiency of electron-hole separation. Herein, the PCN-224/g-C 3 N 4 heterojunction exhibited excellent photocatalytic activity in both disinfection and organic pollutant degradation. Under visible light irradiation (λ > 420 nm) for 3 h, it completely degraded phenol and effectively inactivated E. coli . In the photocatalytic process, electrons migrate from the conduction band of g-C 3 N 4 to PCN-224, while holes transfer from the valence band of PCN-224 to the valence band of g-C 3 N 4 , thereby generating \({\text{O}}_{2}^{{\bullet - }}\) and h + radicals. These generated radicals effectively oxidize and degrade phenol.
研究领域:
材料科学
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环境科学
·
化学工程
·
纳米技术
✓ 已验证
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2020
·
IF 7.632
Yong-Ting Li,Xiao-Li Zhang,Zhi-Kun Peng,Pu Liu,Xiu-Cheng Zheng
It is a crucial and urgent task to develop high performance catalysts for the hydrolysis of ammonia borane (NH3BH3, AB), which is presently thought to be an effective strategy for hydrogen generation. In this work, we immobilize the ultrafine RuNi alloy nanoparticles in the network of hierarchical porous g-C3N4 thin sheets with a facile adsorption–in situ reduction method. The structural and physicochemical properties of the as-prepared catalysts are studied using various techniques. The influence of different molar ratios of Ru to Ni in the catalysts on the hydrolytic dehydrogenation rate of AB is investigated to optimize the best one. The detailed reaction kinetics and the enhancing effect of NaOH with different dosages on the hydrolysis rate are studied through a series of experiments. Catalyzed by the optimal catalysts (denoted as Ru0.5Ni0.5/p-g-C3N4), the hydrolysis reaction is first-order and near zero-order relative to the Ru and AB concentrations, respectively. The corresponding turnover frequency reaches 840.3 min–1, and the apparent activation energy is as low as 14.1 kJ mol–1, which are greatly superior to many similar or counterpart catalysts previously reported. The results indicate the potential of the bimetallic alloy catalysts for the hydrolytic dehydrogenation of hydrogen storage materials.
研究领域:
材料科学
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能源化学
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催化反应
✓ 已验证
DOI
高影响因子
Desalination and Water Treatment
·
2024
·
IF 1
Fang-yan Chen,Min-keng He,Yu-bin Tang,Cheng-yi He,Ke-ke Shu,Ming-yang Li
A core-shell g-C 3 N 4 /SiO 2 nanocomposite was successfully synthesized by depositing g-C 3 N 4 , obtained from the sublimation of melamine and subsequent polymerization reaction in the gaseous phase, on the nano-silica. The as-prepared g-C 3 N 4 /SiO 2 was characterized by X-ray diffraction, Fourier transform infrared spectroscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, N 2 adsorption–desorption, UV-vis diffuse reflectance spectroscopy. The visible-driven photocatalytic activity of g-C 3 N 4 / SiO 2 was evaluated by the degradation of tetracycline. The results indicate that the specific surface area of g-C 3 N 4 /SiO 2 is 97.32 m 2 /g, which is 6.74 times as high as that of bulk g-C 3 N 4 (14.44 m 2 /g). Compared to bulk g-C 3 N 4 , g-C 3 N 4 /SiO 2 composite exhibits significantly enhanced photocatalytic activity for degradation of tetracycline and can degrade 72.7% of tetracycline within 60 min under visible-light irradiation. The photodegradation rate constant of tetracycline over g-C 3 N 4 /SiO 2 is 7.2 times as high as that over bulk g-C 3 N 4 . The greatly enhanced photocatalytic activity of g-C 3 N 4 /SiO 2 is due to coupling enlarged surface areas with the contribution of SiO 2 in inhibition of the recombination of photo-induced electron-hole pair.
研究领域:
材料科学
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环境科学
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化学工程
✓ 已验证
DOI
高影响因子
Catalysis Science & Technology
·
2021
·Vol. 11
·期 16
·5579-5589
·
IF 6.119
Qixiao Gai,Shoutian Ren,Xiaochun Zheng,Wenjun Liu,Quanli Dong
Transition metal co-catalysts exhibit considerable potential in the photocatalytic water splitting process, but their limited activity and poor stability inhibit their extensive application, and therefore effective schemes are required to further enhance their co-catalytic performance. In this article, 2D/2D C3N4/CdS heterogeneous photocatalysts are first synthesized, and then CoNi alloyed NPs are selectively loaded on their CdS nanosheets by a convenient photodeposition method. The CoNi loading amount and Co/Ni ratio are adjusted by the photodeposition time and precursor Co2+/Ni2+ ratio, respectively. Meanwhile, Co–S bonds are formed between CdS and CoNi NPs. Their optimal hydrogen evolution rate can reach up to 2936.65 μmol g−1 h−1, which is higher than that of C3N4/CdS with Co, Ni or Pt as co-catalysts (i.e. 844.59, 2385.96 and 2486.66 μmol g−1 h−1), respectively. The enhanced photocatalytic performance should be due to the following three points: (1) the formation of the 2D/2D C3N4/CdS heterojunction; (2) the optimized Gibbs free energy of the CoNi co-catalysts; (3) the formation of Co–S bonds between CoNi and CdS. Our work provides a cost-effective scheme to exploit stable and efficient photocatalysts.
研究领域:
材料科学
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能源化学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2018
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IF 6.735
Ning Li,Yu Tian,Jianhui Zhao,Jun Zhang,Wei Zuo,Lingchao Kong,Hao Cui
In this study, a newly-designed Z-scheme g-C 3 N 4 @ZnO heterostructure was synthesized by 3D ZnO controllable deposition on 2D g-C 3 N 4 nanosheets using thermal atomic layer deposition. The activity of 2D/3D g-C 3 N 4 @ZnO was evaluated by photocatalytic degradation of cephalexin under simulated sunlight. Results showed that the g-C 3 N 4 @ZnO photocatalyst achieved 98.9% degradation and 72.8% mineralization of cephalexin within 60 min of illumination. This degradation process fitted to the pseudo first order dynamic model with reaction rate constant of 0.0735 min −1 , 5.4 and 8.1 times higher than that of pure g-C 3 N 4 and ZnO, respectively. Consecutive degradation experiments revealed the excellent stability and recyclability of 2D/3D g-C 3 N 4 @ZnO photocatalyst. Mechanism exploration found the enhanced photocatalytic activity was mainly ascribed to the strong oxidizability of active species generated on Z-scheme g-C 3 N 4 @ZnO. Besides, the oxidative species, especially h + and · OH played significant roles in the degradation process. Moreover, the degradation intermediates were identified through HPLC/MS/MS analysis and the possible pathway of cephalexin decomposition was proposed accordingly. The Z-scheme 2D/3D g-C 3 N 4 @ZnO was also proved effective for contaminants removal in real sewage. This study provided a new platform for controllable creation of Z-scheme photocatalysts with broad application prospects in contaminants remediation from aquatic environment under solar light.
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
JOURNAL OF ALLOYS AND COMPOUNDS
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2020
·
IF 4.65
Lei Cui,Siliang Liu,Fangke Wang,Jingyao Li,Yanhua Song,Ye Sheng,Haifeng Zou
In this work, uniform g-C 3 N 4 shells have grown on the surface of electrospinning TiO 2 nanofibers to form one dimensional core/shell structured TiO 2 /g-C 3 N 4 nanofibers by a facial melamine-involved vapor deposition approach. During the heat treatment process in a simple setup, the TiO 2 nanofibers served as supports to prevent the collapses and aggregations of g-C 3 N 4 while forming heterojunctions with g-C 3 N 4 at the interface. The as prepared heterogeneous TiO 2 /g-C 3 N 4 photocatalyst exhibited remarkably enhanced visible light photocatalytic activity for RhB degradation by maxing heterojunctions at the core/shell interface. The photodegradation reaction rate constant of the obtained heterojunction is 0.064 min −1 , which is 4.0 times that of pure g-C 3 N 4 (0.016 min −1 ). To reach higher RhB degradation efficiency (>90%), TiO 2 /g-C 3 N 4 shortened the irradiation time by 60 min compared with individual components (pure g-C 3 N 4 or TiO 2 nanofibers). The remarkably high photocatalytic performances are mainly ascribed to the synergetic effect of efficient photogenerated charge separation properties and decreased electron transfer resistance of the heterojunctions formed between g-C 3 N 4 and TiO 2 . We believe the proposed simple method and setup is an attractive strategy for constructing one dimensional g–C 3 N 4 –based nano-heterojunctions with excellent photocatalytic properties.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2019
·
IF 5.107
Yuqi Cui,Li-chao Nengzi,Jianfeng Gou,Yan Huang,Bo Li,Xiuwen Cheng
Z-scheme heterojunction photocatalyst can simultaneously reduce the recombination of photo-generated electron-hole pairs and preserve its outstanding redox ability during the process of photocatalytic reaction. In this study, Z-scheme MIL-53(Fe)/α-Bi 2 O 3 /g-C 3 N 4 photocatalyst was successfully fabricated via an accessible method and comprehensive characterized by XRD, FT-IR, SEM, TEM, XPS, N 2 adsorption-desorption isotherms, UV–vis diffuse reflection spectroscopy and photoelectrochemical analysis. The as-obtained MIL-53(Fe)/α-Bi 2 O 3 /g-C 3 N 4 composite exhibited superior photocatalytic activity for amino black 10B degradation than that of pure g-C 3 N 4 , α-Bi 2 O 3 , MIL-53(Fe) and α-Bi 2 O 3 /g-C 3 N 4 binary composite under visible light irradiation and the photodegradation rate would achieve the maximum when the mass fraction of MIL-53(Fe) was 32% in ternary composite. The enhanced photocatalytic performance of MIL-53(Fe)/α-Bi 2 O 3 /g-C 3 N 4 ternary composite could be mainly ascribed to improved visible light absorption range and the construction of an effective interfacial heterojunction driven by direct solid-state dual Z-scheme mechanism, which significantly facilitates the separation and transfer of photo-generated charge carriers. Eventually, the as-prepared ternary composite was confirmed to have prominent stability and reusability after consecutive 4 recycling run.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
JOURNAL OF SOILS AND SEDIMENTS
·
2022
·Vol. 22
·期 7
·2009-2021
·
IF 3.536
Liu Quanfeng,Yu Jiang,Jiang Yinying,Zhong Chengwei,Ding Senxu,Zhou Peng,Jin Yuanxiao
Purpose Soil organic matter pollution is a serious threat to the human living environment. The purpose of this paper is to investigate the effect of MIL-101(Fe)/g-C 3 N 4 catalyzed peroxynitrite degradation of 2-chlorophenol in soil and to analyze the reaction mechanism and further to explore the optimal parameters of this reaction system with utilizing the mathematical model. Methods MIL-101(Fe)/g-C 3 N 4 was successfully obtained by hydrothermal synthesis method by growing MIL-101(Fe) on the surface of g-C 3 N 4 to catalyze the degradation of 2-CP (2-chlorophenol) in soil by sodium persulfate. The influence factors on the removal rate of 2-CP were analyzed by the response surface methodology (RSM) and combined with theoretical calculations. RSM can be used to model continuous variable surfaces with less data and determine the optimal level range. Results MIL-101(Fe)/g-C 3 N 4 had a good catalytic performance due to its good catalytic properties and the adsorption of g-C 3 N 4 on 2-CP in the system and made the best removal rate of 2-CP increase to 91.2%. The correlation of model fitting results was significant, and the verification of its optimal parameters yielded results with an error of only 4.1%. Conclusion Further studies revealed that SO 4 •− and • OH were the reactive radicals, and SO 4 •− was the dominant, which impelled Fe 2+ and Fe 3+ to interconvert in the complex system. Possible degradation pathways were derived by analyzing the intermediates. Generally, this experiment provides some ideas for future research of MOFs in soil organic pollutant removal systems. Graphical abstract
研究领域:
环境科学
·
催化化学
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry A
·
2019
·Vol. 8
·期 6
·2995-3004
·
IF 10.733
Peng Wen,Kefei Zhao,Hui Li,Jiangsheng Li,Jing Li,Qing Ma,Scott M. Geyer,Lin Jiang,Yejun Qiu
Very recently, transition metal phosphides (TMPs) have emerged as low-cost and robust co-catalysts for decorating graphitic carbon nitride (g-C3N4) for photocatalytic hydrogen (H2) evolution. However, to date, little work has been done regarding the decoration approaches to hybridize TMPs on the g-C3N4 surface with homogeneous dispersion and intimate interfacial contact. Herein, we present a facile and convenient route to in situ incorporate g-C3N4 nanosheets (NSs) and Ni2P nanocrystal (NC) co-catalysts via a one-step co-heating solution approach. The Ni2P/g-C3N4 (in situ) hybrid photocatalyst achieved a far superior H2 production rate (2849.5 μmol g−1 h−1) and durability (no decrease after 4 cycles of reaction within 20 h) compared to the Ni2P/g-C3N4 (self-assembly) sample. The apparent quantum yield (AQY) of 18.8% at 420 nm was also much higher than that of other TMP co-catalyst loaded g-C3N4 hybrid photocatalysts. A possible Ni(δ+)–N(δ−) chemical coupling in the Ni2P/g-C3N4 (in situ) hybrid composite was proposed and corroborated by X-ray photoelectron spectroscopy (XPS) and X-ray absorption spectroscopy. The unique Ni(δ+)–N(δ−) chemical bonding states between g-C3N4 and Ni2P significantly accelerate the photo-generated charge-carrier separation and extraction from g-C3N4, as well as maintaining the H2 production durability. We believe that the hybridization route presented in this work will be extended to construct other TMP integrated photocatalysts toward efficient and stable solar water splitting.
研究领域:
材料科学
·
能源化学
·
表面化学
✓ 已验证
DOI
高影响因子
MICROCHIMICA ACTA
·
2021
·Vol. 188
·期 12
·1-11
·
IF 5.833
Wang Xiao,Liao Xiaochen,Zhang Bingjian,Zhang Mengmeng,Mei Lisha,Wang Fangwai,Chen Siyu,Qiao Xiuwen,Hong Chenglin
Abstract Carcinoembryonic antigen levels in the human body reflect the conditions associated with a variety of tumors and can be used for the identification, development, monitoring, and prognosis of lung cancer, colorectal cancer, and breast cancer. In this study, an amperometric immunosensor with CuCo/carbon nanocubes (CuCo/CNC) as the signal label is constructed. The bimetal-doped carbon skeleton structure has a high specific surface area and exhibits good electrocatalytic activity. In addition, Au/g-C 3 N 4 nanosheets (Au/g-C 3 N 4 NSs) are used to modify the substrate platform, facilitating the loading of more capture antibodies. The reaction mechanism was explored through electrochemical methods, X-ray powder diffraction, X-ray photoelectron spectroscopy, and other methods. Kinetic studies have shown that CuCo/CNC have good peroxidase-like activity. In addition, the electrocatalytic reduction ability of CuCo/CNC on hydrogen peroxide can be monitored using amperometric i – t curve (− 0.2 V, vs. SCE), and the response current value is positively correlated with the CEA antigen concentration. The prepared electrochemical immunosensor has good selectivity, precision, and stability. The dynamic range of the sensor was 0.0001–80 ng/mL, and the detection limit was 0.031 pg/mL. In addition, the recovery and relative standard deviation in real serum samples were 97.7–103 % and 3.25–4.13 %, respectively. The results show that the sensor has good analytical capabilities and can provide a new method for the clinical monitoring of CEA. Graphic abstract
研究领域:
生物医学工程
·
肿瘤学
·
分析化学
✓ 已验证
DOI
高影响因子
Journal of the American Chemical Society
·
2017
·
IF 13.858
Shuai Xu,Peng Zhou,Zehui Zhang,Changjun Yang,Bingguang Zhang,Kejian Deng,Steven Bottle,Huaiyong Zhu
Selective oxidation of 5-hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA) is one of the key reactions for producing chemical commodities from biomass and their derivatives. The challenge for this reaction is to develop an efficient catalytic process that can be conducted under mild conditions (room temperature and atmospheric pressure, using oxygen molecules in air as the oxidant) and a recyclable catalyst. Herein we report a photocatalyst of cobalt thioporphyrazine (CoPz) dispersed on g-C3N4 (abbreviated as CoPz/g-C3N4), which exhibits excellent catalytic activity toward the selective oxidation of HMF into FDCA under simulated sunlight using oxygen molecules in air as a benign oxidant. For example, an FDCA yield of 96.1% in an aqueous solution at pH = 9.18 is achieved at ambient temperature and air pressure. At lower pH (4.01), the product generated is 2,5-diformylfuran. Hence, it is possible to control the reaction outcome by control of the pH of the reaction system. g-C3N4 itself is not a suitable catalyst for the selective oxidation because under the experimental conditions g-C3N4 generates hydroxyl radicals that initiate processes that oxidize HMF directly to CO2 and H2O. CoPz on the other hand activates O2 to give singlet oxygen (1O2), which more controllably oxidizes HMF to FDCA albeit at a more moderate yield (36.2%). The strong interaction between the CoPz and g-C3N4 in the CoPz/g-C3N4 catalyst is experimentally evidenced, which not only improves accessibility of the CoPz sites and makes the catalyst recyclable but also disables the hydroxyl radical generation by g-C3N4 and promotes 1O2 generation on the CoPz sites, significantly enhancing the catalytic performance. This study demonstrates the potential for efficient non-noble metal photocatalysts for organic transformations driven by sunlight.
研究领域:
化学工程
·
催化科学
·
环境科学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）