Materials Today Communications
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2023
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IF 3.8
Cheng Hu,Lianhong Zhang,Qin Ye,Qiang Li
The ability of photocatalysts to combat environmental pollution can be effectively improved by defect modulation. This paper developed a donor-acceptor (D-A) precursor system using urea as the hydrogen bond donor and cyanoacetic acid as the hydrogen bond acceptor to successfully synthesize modified g-C 3 N 4 (CA-CNx). The results showed that while cyanoacetic acid addition contributed to the formation of N defects in g-C 3 N 4 , but cyanoacetic acid overuse caused structural disorder in CA-CNx. A decrease in the g-C 3 N 4 band gap and an improvement in the photogenerated carrier mobilities due to the inclusion of N defects may lead to more effective usage of visible light. The highest catalytic activity for methylene blue (MB) solution (40 mg/L) was demonstrated by the modified g-C 3 N 4 synthesized by adding 0.4 g cyanoacetic acid, and the degradation rate of the MB solution reached 90.4 % within 100 min. The proposed primary kinetic constant was 6.91 times higher than the original g-C 3 N 4 . According to free radical scavenging tests, superoxide radicals are the predominant active species during the catalytic breakdown of MB processes. This method provides a novel idea to producing g-C 3 N 4 with N-defects and the opportunity to comprehend the impact of structural defects in enhancing semiconductor photocatalytic activity.
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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光催化
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DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2023
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IF 22.1
Chao Xue,Peifang Wang,Huinan Che,Wei Liu,Bin Liu,Yanhui Ao
A novel photocatalytic system was developed for the simultaneous degradation of organic contaminant and generation of H 2 O 2 based on molecular-engineered carbon nitride (AQ-CN x ). The AQ-CN x was synthesized by simultaneously introducing N defects and anthraquinone-2-carboxylic acid. Synergistically, the AQ-CN x exhibited a H 2 O 2 production rate of 36.41 mM h −1 g −1 , which is 7.87 times as that of CN. More importantly, atenolol (ATL) can promote H 2 O 2 production, which in turn increases ATL degradation. Density functional theory (DFT) calculations demonstrate that N defects provide more sites for O 2 adsorption and AQ acts as an electron-acceptor to facilitate the separation of photogenerated electrons and holes. Independent gradient model based on Hirshfeld partition (IGMH) analysis shows that van der Waals interaction between AQ-CN x and ATL enhances the degradation efficiency. This work provides a new idea for the effective degradation of pollutants and simultaneous generation of H 2 O 2 .
研究领域:
环境科学
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材料科学
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化学工程
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DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2024
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IF 9.4
Baoji Miao,Yange Cao,Imran Khan,Qiuling Chen,Salman Khan,Amir Zada,Muhammad Shahyan,Sharafat Ali,Rizwan Ullah,Jinbo Bai,Muhammad Rizwan,Abdullah M.S. Alhuthali
The realization of 2D/2D Van der Waals (VDW) heterojunctions represents an advanced approach to achieving superior photocatalytic efficiency. However, electron transfer through Van der Waals heterojunctions formed via ex-situ assembly encounters significant challenges at the interface due to contrasting morphologies and potential barriers among the nanocomposite substituents. Herein, a novel approach is presented, involving the insertion of a phosphate group between copper phthalocyanine (CuPc) and B-doped and N -deficient g-C 3 N 4 (BDCNN), to design and construct a Van der Waals heterojunction labeled as xCu[acs]/yP-BDCNN. The introduction of phosphate as a charge modulator and efficient conduit for charge transfer within the heterojunction resulted in the elimination of spatial barriers and induced electron movement from BDCNN to CuPc in the excited states. Consequently, the catalytic central Cu 2+ in CuPc captured the photoelectrons, leading to the conversion of CO 2 to C 2 H 4 , CO and CH 4 . Remarkably, this approach resulted in a 78-fold enhancement in photocatalytic efficiency compared to pure BDCNN . Moreover the findings confirm that the 2D-2D 4Cu[acs]/9P-BDCNN sheet-like heterojunction effectively boosts photocatalytic activity for persistent pollutants such as methyl orange (MO), methylene blue (MB), rhodamine B (RhB), and tetracycline antibiotics (TCs). The introduction of “interfacial interacting” substances to establish an electron transfer pathway presents a novel and effective strategy for designing photocatalysts capable of efficiently reducing CO 2 into valuable products.
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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产品关联
DOI
PubMed
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2023
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IF 22.1
Junpeng Yue,Hanpei Yang,Chen Liu,Qiang Zhang,Yanhui Ao
A new strategy to realize efficient removal of organics from water through photo-self-Fenton was investigated. Characterizations and calculations demonstrated that a novel twin carbon nitride with abundant surficial N-defects and compressed π-π layer stacking can be constructed by thermal polymerization of urea under suitable basicity. Synergistically, the twins exhibited an in-situ H 2 O 2 producing at a rate as high as 26.36 mM h −1 g −1 at 420 nm that exceeded most reported C 3 N 4 , and their mineralization rates for Tetracycline Hydrochloride, Bisphenol A , Ciprofloxacin, and Rhodamine B reached 8.8, 15.2, 9.1, and 13 times higher than that of pristine C 3 N 4 . It is concluded that enriching both of photogenerated electrons and molecular oxygens on specific sites plays a crucial role during photocatalysis-self-Fenton process. Particular attentions have to be paid to build structures achieving one and two-electron reduction of O 2 , and activation of H 2 O 2 to •OH simultaneously.
研究领域:
环境科学
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材料科学
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化学工程
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产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2024
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IF 8.1
Yuan Zhang,Kangping Cui,Xueyan Liu,Minshu Cui,Xing Chen,Yuchao Tang,Haiyang Li
Metal-based catalyst could be used for efficient peroxymonosulfate (PMS) activation, but inevitably suffered from metal ion leaching. Metal-free graphitic carbon nitride (g-C 3 N 4 ) materials that can activate PMS are more conducive for practical water treatment. In this study, g-C 3 N 4 with both N-defects and P-doping (CN-NP) was synthesized, which mainly produce singlet oxygen ( 1 O 2 ), and 97 % of 4-CP (4-Chlorophenol) was removed by CN-NP/PMS/Vis reaction system within 60 min. The active species was identified by quenching experiments and electron spin resonance (ESR) tests, and the origin of mainly active species was further verified by the concentration change of PMS during the reaction. It was verified by experiments and theoretical calculations that the introduction of N-defects led to the separation of photoinduced electron-hole pairs and improved photocatalytic activity. Notably, density functional theory (DFT) revealed that both N-defects and P-doping are electron-deficient sites, and P-doping acts as the main PMS adsorption site to promote the loss of electrons from PMS to generate 1 O 2 . In addition, the catalysts developed in this research were anticipated to be applied in real wastewater treatment, contributing to further comprehend the mechanisms of element doping and defect modification in g-C 3 N 4 activating PMS, and providing new insights for the design of PMS-activating catalysts.
研究领域:
环境科学
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材料科学
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催化
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水处理
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产品关联
DOI
高影响因子
ELECTROCHIMICA ACTA
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2023
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IF 6.6
Liangchen Yue,Hao Guo,Junjie Hua,Miao Yu,Keliang Liu,Xian Yang,Jianzhong Liu,Jun Cheng
To develop a low-cost acidic water electrolysis catalyst with high efficiency and stability and low Ir content, a catalyst with highly dispersed Ir/Fe complex sites (∼ 5 wt% Ir) was synthesized by a simple carbonization and oxidation process. N-defective g-C 3 N 4 (N CN) was introduced to enhance the support effect between metal nanoparticles and CN bases and the intrinsic catalytic activity for the oxygen evolution reaction (OER). N CN provided more active sites and adjusted the electronic structure of CN. Compared with the original single Ir catalyst, the electrons of the Ir-Fe metal catalyst were transferred from the base to the metal, which maintained the high OER performance and stability of the catalyst. Density functional theory calculations demonstrated that the Gibbs free energy of Ir/Fe@N CN was greatly reduced during O*→OOH* as the rate-determining step. The overpotential of the Ir/Fe@N CN catalyst was 242 mV at 10 mA/cm 2 , and its mass activity (612.6 A/g) was much higher than that of IrO 2 (88.6 A/g), showing excellent OER performance. This study provides a new strategy for the design and optimization of highly efficient and low-cost acidic Ir/transition metal OER catalysts.
研究领域:
催化
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材料科学
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电化学
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能源材料
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产品关联
DOI
高影响因子
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