CARBON
·
2022
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IF 11.307
Xiang Yu,Yue Zhan,Tingting Fan,Yuqi Zhang,Shunqin Liang,Limin Sun,Xiaoli Hu,Weiping Fang,Zhou Chen,Xiaodong Yi
The stabilization and transport of the reactants, intermediates and products are significant to rational design of an industrial catalyst. In this work, we encapsulated the surface of Pd/g-C 3 N 4 catalyst with acrylic acid (AA) using a photo-induced grafting method to mimic the 3-dimensional nature of enzymes. A combined characterization and ab initio calculation revealed that AA ligands on the surface controlled the adsorption and diffusion behaviors of the reactants, rather than alter the electronic or geometric properties of Pd active centers. The optimized catalyst (Pd/CNA-4) significantly enhances isoprene partial hydrogenation activity without a decline in semi-hydrogenation selectivity. This approach can be further optimized by changing the types of the encapsulating ligands and can meet other specific catalytic reactions to regulate their conversion and selectivity and is therefore expected to extend to other areas of heterogeneous catalysis .
研究领域:
催化化学
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材料科学
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理论化学
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2020
·
IF 10.652
Ze Yin,Minguang Han,Zhao Hu,Li Feng,Yongze Liu,Ziwen Du,Liqiu Zhang
For efficient usage of visible light, Pd loading graphitic carbon nitride (Pd/g-C 3 N 4 ) hybrids were synthesized and peroxymonosulfate (PMS) was accompanied to improve the photoactivities of Pd/g-C 3 N 4 . The photocatalytic system consisting of Pd/g-C 3 N 4 , PMS and visible light (Pd/g-C 3 N 4 -PMS-Vis) exhibited higher bezafibrate (BZF) removal efficiency than Pd/g-C 3 N 4 -PMS, Pd/g-C 3 N 4 -Vis, g-C 3 N 4 -PMS, g-C 3 N 4 -Vis, and g-C 3 N 4 -PMS-Vis systems, which can be ascribed to the electron transfer from Pd/g-C 3 N 4 to PMS. Density functional theory (DFT) calculation proved that the chemical bond interaction forming between Pd and g-C 3 N 4 inspired the electron excitation, separation and transportation. Meanwhile, Pd particles with local surface plasma resonance (LSPR) phenomenon could also enhance the visible light adsorption. Notably, the photocurrent response of Pd/g-C 3 N 4 was significantly improved with PMS, demonstrating the photoinduced electrons on Pd/g-C 3 N 4 are capable to immigrate to PMS. The added PMS can perform as electron acceptors, thus favoring the quantum efficiency of photoinduced charge carriers to form SO 4 − . The BZF degradation mechanism was clarified by the addition of different scavengers and the major reaction active species were hydroxyl radicals (OH ) and sulfate radical (SO 4 − ). Four possible pathways in the degradation of BZF were also put forward via LC-MS/MS analysis (R-oxy substituent, oxidation dichlorination, OH-addition and oxidation deaminization). In the 2%Pd/g-C 3 N 4 -PMS-Vis system, an obvious decrease of genetic toxicity was observed because of the high removal efficiency and final low concentration of BZF. The results of this research underlined great prospective of Pd/g-C 3 N 4 catalysts and provided a potential approach to photocatalytically remedy the polluted water by micropollutants.
研究领域:
环境科学
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催化
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水处理
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光化学
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产品关联
DOI
高影响因子
DALTON TRANSACTIONS
·
2023
·Vol. 52
·期 47
·17974-17980
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IF 4
Liqing Li,Xin Deng,Jiani He,Huan Zhang,Li Li,Lihua Zhu
Herein, we report that Pd nanoparticles (NPs) anchored on graphitic nitride carbon (Pd/g-C3N4) catalysts with various Pd contents (1.55 wt%, 0.14 wt%, 0.04 wt%) are successfully prepared via a simple NaBH4 reduction method, exhibiting excellent catalytic activity and selectivity toward 4-aminophenol (4-AP) in 4-nitrophenol (4-NP) selective hydrogenation. 4-NP is completely converted to 4-AP (yield ∼ 100%) under quite moderate reaction conditions (40 °C, 2.0 MPa H2 and 5 min) over the 1.55 wt% Pd/g-C3N4 catalyst, with a high reaction rate r = 134.4 mol4-NP molPd−1 min−1. The excellent catalytic performance can be attributed to the following reasons: (1) a higher ratio of Pd(0)/Pdn+ provides much more exposed active sites for the potential adsorption and activation of the reactants, which is beneficial for increasing the reaction rate and catalytic activity; (2) Pd NPs are highly dispersed on g-C3N4 due to the strong interaction of Pd–N or Pd–C; (3) the interfacial synergism effect between Pd NPs and g-C3N4 enables the effective adsorption and activation of H2 (4-NP) at Pd (g-C3N4), promoting the catalytic hydrogenation of 4-NP and improving their catalytic properties. In addition, this catalyst has superior reusability.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2018
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IF 6.434
Jiafeng Ding,Gaoyuan Long,Yang Luo,Runze Sun,Mengxia Chen,Yajun Li,Yanfang Zhou,Xinhua Xu,Weirong Zhao
Polychlorinated dibenzo- p -dioxins (PCDDs), as a group of notorious anthropogenic environmental toxicants, are arguably ubiquitous in nature. In this study, we investigated the photocatalytic reductive dechlorination of 2-chlorodibenzo- p -dioxin (2-CDD) over Pd/g-C 3 N 4 catalysts under UV–vis irradiation. The g-C 3 N 4 and a series of Pd/g-C 3 N 4 catalysts were prepared by thermal polymerization and mechanical mixing-illumination method and characterized by XRD, TEM, BET, SEM and UV–vis DRS analyses. Among all the samples, the Pd/g-C 3 N 4 (5 wt%) yielded the optimal dechlorination activity with a total 2-CDD conversion of 54% within 4 h, and 76% of those converted 2-CDD were evolved to dibenzo- p -dioxin (DD). The kinetics of dechlorination could be described as pseudo-first-order decay model (R 2 > 0.84). Corresponding rate constants (k) increased from 0.052 to 0.17 h −1 with Pd contents up to 5 wt% and decreased to 0.13 h −1 with a 10 wt% of Pd. The enhanced activities originated from the surface plasmonic resonance (SPR) effect of Pd nanoparticles and the formation of Schottky barrier between Pd and g-C 3 N 4 , which extend the spectrum responsive range and suppress the charge recombination of g-C 3 N 4 . This is the first report on the photocatalytic reductive removal of PCDDs and may provide a new approach for PCDDs pollution control.
研究领域:
环境科学
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化学工程
✓ 已验证
DOI
高影响因子
DIAMOND AND RELATED MATERIALS
·
2025
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IF 5.1
Ruixi Li,Jiani He,Huan Fu,Qingqing Liu,Lihua Zhu,Weizhen Wang,Liqing Li,Zhiqing Yang,Huan Zhang,Hengqiang Ye
Graphitic carbon nitride (g-C 3 N 4 ) is prepared by high-temperature annealing method, followed by the deposition of noble metal (Pt, Rh, Pd, Ru) nanoparticles and then variants 0.38 wt%, 0.76 wt%, 2.51 wt%Pd/g-C 3 N 4 catalysts are obtained using NaBH 4 reduction method. Pd/g-C 3 N 4 exhibits excellent catalytic activity in nitroarenes selective hydrogenation under quite moderate reaction conditions (e.g., p-nitroacetophenone hydrogenation, 96.5 % conversion with 100 % selectivity to p-aminoacetophenone and 15.6 min −1 -turnover frequency at 3.0 MPa H 2 , 20 °C, 0.33 h). Additionally, the Pd/g-C 3 N 4 samples are used for 1, 3-dinitrobenzene hydrogenation, 2.51 wt%Pd/g-C 3 N 4 obtains 97.6 % conversion and 100 % selectivity to m-nitroaniline (20 °C, 3.0 MPa H 2 , 1 min). TOF: 2.51 wt%Pd/g-C 3 N 4 -2.02 s −1 > 0.76 wt%Pd/g-C 3 N 4 -0.56 s −1 > 0.38 wt%Pd/g-C 3 N 4 -0.54 s −1 for 1, 3-dinitrobenzene hydrogenation. Characterizations of XRD, XPS, AC-STEM, AC-STEM elemental analysis, TEM, HRTEM, BET and H 2 -TPD, etc. demonstrate that the Pd nanoparticles in Pd/g-C 3 N 4 have high dispersion and surface/interface synergy of Pd-g-C 3 N 4 , probably contributing to the catalyst's enhanced selectivity, activity, and stability in nitroaromatics hydrogenation. In addition, the catalyst is recyclable and highly durable for nitroaromatics hydrogenation.
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DOI
高影响因子
Nano Research
·
2021
·Vol. 15
·期 4
·2928-2934
·
IF 8.897
Xiao Xudong,Lin Siying,Zhang Liping,Meng Huiyuan,Zhou Jing,Li Qi,Liu Jianan,Qiao Panzhe,Jiang Baojiang,Fu Honggang
The formation of chemical bonds between metal ions and their supports is an effective strategy to achieve good catalytic activity. However, both the synthesis of active metal species on a support and control of their coordination environment are still challenging. Here, we show the use of an organic compound to produce tubular carbon nitride (TCN) as a support for Pd nanoparticles (NPs), creating a composite material (NP-Pd-TCN). It was found that Pd ions preferentially bind with the electron-rich N atoms of TCN, leading to strong metal-support interactions that benefit charge transfer from g-C 3 N 4 to Pd. X-ray absorption spectroscopy further revealed that the metal-support interactions resulted in the formation of Pd-N bonds, which are responsible for the improvement in the charge dynamics as evidenced by the results from various techniques including photoluminescence (PL) spectroscopy, photocurrent measurements, and electrochemical impedance spectroscopy (EIS). Owing to the good dynamical properties, NP-Pd-TCN was used for photocatalytic hydrogen evolution under visible-light irradiation ( λ > 420 nm) and an excellent evolution rate of ∼ 381 µmol·h −1 (0.02 g of the photocatalyst) was attained. This work aims to promote a strategy to synthesize efficient photocatalysts for hydrogen production by controllably introducing metal nanoparticles on a support and in the meantime forming chemical bonds to achieve intimate metal-support contact.
研究领域:
材料科学
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化学
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产品关联
DOI
高影响因子
Catalysts
·
2025
·Vol. 15
·期 5
·442
·
IF 4
Zhe Wang,Xiaoliang Li
A series of Pd/g-C3N4catalysts were synthesized using different graphitic carbon nitride precursors, and were found to exhibit significant variations in catalytic performance for solvent-free selective catalytic oxidation of benzyl alcohol. Through comprehensive characterization (XRD, N2-BET, ICP-AES, TEM, and XPS), the experimental results found that the nitrogen chemical configuration and surface Pd2+concentration critically determined the catalytic efficiency. Among the various nitrogen species, N-(C)3-type nitrogen demonstrated the strongest influence on catalytic activity, which was positively correlated with its abundance in g-C3N4matrices. In particular, g-C3N4derived from dicyandiamide contained the highest N-(C)3type nitrogen content. When serving as Pd nanoparticle support, this material simultaneously achieved the best Pd2+surface concentration and catalytic performance compared to the other g-C3N4-supported catalysts.
研究领域:
催化化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Yaxin Li,Wei Qin,Xinyang Li,Qi Zhu,Fu-quan Bai,Tao Tian
It is highly desirable to enhance the charge separation and introduce catalytic functions for efficient water splitting into hydrogen on g-C 3 N 4 . Herein, heterojunctions of PCN-222(M)/g-C 3 N 4 -AA were successfully synthesized through the in-situ hydrothermal method, where metallic ions (M) were strategically incorporated into porphyrinic metal-organic framework (MOF) ligands. This heterojunction design strategy is considered to establish directional charge transfer channels for photogenerated electron-hole (e − -h + ) pairs and thereby enhance its separation efficiency. Remarkably, the 1 % PCN-222(Pd)/g-C 3 N 4 -AA composite demonstrated superior photocatalytic hydrogen evolution performance, achieving a rate of 2338.17 μmol·g −1 ·h −1 . This rate was 3.23 times higher than that of pure g-C 3 N 4 and 2.79 times higher than that of g-C 3 N 4 -AA. The composite morphology was characterized by a series of physicochemical properties. Bandgap analysis via Tauc plot revealed that metal ion doping in the porphyrin center effectively modulates the HOMO-LUMO levels at the composite interface. First-principles calculations coupled with hydrogen adsorption free energy analysis elucidated how interfacial engineering between PCN-222(M) and g-C 3 N 4 -AA governs heterostructure formation and charge transfer pathways. This work systematically deciphers the synergistic effects of bimetallic MOF integration and provides insights into the underlying photocatalytic reaction mechanism.
研究领域:
材料科学
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纳米技术
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催化
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能量转换
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物理化学
✓ 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）