SEPARATION AND PURIFICATION TECHNOLOGY
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2024
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IF 8.1
Ying Wang,Zaiwen Lin,Yan Song,Haotian Wu,Jing Yu,Jiahui Zhu,Qi Liu,Ying Li,Shusen Chen,Jun Wang
Commencing with the goal of establishing a more stable coordination structure for uranium, our approach drew inspiration from the alternating single and double bonds found in benzene rings and amidoxime groups. A uranium adsorption material featuring a π-electron conjugated system is devised. This system is designed by grafting 2-cyanobenzaldehyde, 3-cyanobenzaldehyde, and 4-cyanobenzaldehyde onto bamboo strips (BS) via aldol condensation and hydrolysis reactions, resulting in the creation of 2-amidoxime phenyl BS (oBS-AO), 3-amidoxime phenyl BS (mBS-AO), and 4-amidoxime phenyl BS (pBS-AO). Among these, oBS-AO exhibits not only the highest uranium adsorption performance (224.6 mg g −1 at pH = 6 and 1.3 mg g −1 in artificial simulated seawater) but also features the most robust π-electron conjugated system, as confirmed by computational and simulation data. Notably, the uranium adsorption capacity of mBS-AO is approximately 46.7 times that of vanadium in ion competition experiments simulating seawater conditions. To delve further into the adsorption mechanism, the role of electrostatic interactions and optimized simulated coordination structures is explored. It becomes evident that the primary adsorption mechanism relies on the formation of a pentacoordination structure, and the stability of this coordination structure iss directly influenced by the strength of the π-electron conjugated system. Furthermore, the double bridging effect of hydrogen bonds serves to further stabilize the coordination structure, facilitating the specific and selective adsorption of uranium.
研究领域:
材料科学
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环境科学
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DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
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2020
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IF 6.155
Xiangang Lin,Xiaojuan Hou,Lixia Cui,Shiqiang Zhao,Hong Bi,Haiwei Du,Yupeng Yuan
Increasing the availability of π-electron in graphitic carbon nitride (g-C 3 N 4 ) can reduce the band gap and thus enhance the photocatalytic hydrogen (H 2 ) generation activity upon exposure to visible light. However, such strategy has not yet been largely applied to increase the H 2 generation of g-C 3 N 4 . Herein, we successfully increased the amount of π-electron in g-C 3 N 4 by incorporating π-electron-rich benzene rings through copolymerization of melamine and trimesic acid in air. The incorporation of benzene rings not only extends the light absorption of g-C 3 N 4 to 650 nm, but also improves the electrical conductivity due to delocalization of π electrons in benzene rings. As a result, a 3.4 times enhancement of photocatalytic H 2 generation was achieved from the g-C 3 N 4 with benzene ring incorporation in comparing with that of pristine g-C 3 N 4 . More interestingly, H 2 generation still occurs under irradiation of the light of λ ≥ 490 nm, above the absorption edge of pristine g-C 3 N 4 (∼ 460 nm), illustrating the positive effectiveness of incorporated benzene rings on enhancing the H 2 generation capacity of g-C 3 N 4 . The present work manifests the advantages of increasing π-conjugated electrons on designing highly active g-C 3 N 4 photocatalysts.
研究领域:
材料科学
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能源化学
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DOI
高影响因子
CHINESE JOURNAL OF CATALYSIS
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2020
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IF 6.146
Feiyue Ge,Shuquan Huang,Jia Yan,Liquan Jing,Feng Chen,Meng Xie,Yuanguo Xu,Hui Xu,Huaming Li
Expanding the optical absorption range of photocatalysts is still a key endeavor in graphitic carbon nitride (g-C 3 N 4 ) studies. Here, we report on a novel thiophene group extending the optical property, which is assigned to n-π* electronic transitions involving the two lone pairs on sulfur (TLPS). The as-prepared samples, denoted as CN-ThA x (where x indicates the amount of ThA added, mg), showed an additional absorption above 500 nm as compared to pristine g-C 3 N 4 . Further, the thiophene group enhanced charge carrier separation to suppress e − /h + pair recombination. The experimental results suggest that the thiophene group can obstruct the polymerization of melem to generate a large plane, thus exposing the lone electron pairs on the sulfur. The photocatalytic activity was evaluated in the decomposition of bisphenol A and H 2 evolution. Compared with g-C 3 N 4 , the optimized CN-ThA 30 sample led to a 6.6- and 2-fold enhancement of the degradation and H 2 generation rates, respectively. The CN-ThA 30 sample allowed for synchronous H 2 production and BPA decomposition.
研究领域:
材料科学
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环境科学
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DOI
高影响因子
Catalysis Science & Technology
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2021
·Vol. 11
·期 16
·5663-5670
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IF 6.119
Mengqi Xue,Daochuan Jiang,Haiwei Du,Zhongjun Li,Hong Bi,Yupeng Yuan
Localizing charge carriers close to catalytically active sites can reduce the charge recombination in photoexcited polymeric carbon nitride (PCN), which thus potentially increases its photocatalytic H2 generation. However, this strategy has not been applied to enhance the photocatalytic performance of PCN. Herein density functional theory (DFT) calculations unravel that N defect (Ndefect) engineered tri-s-triazine units form a highly localized mid-gap state in PCN, which can localize the π electrons for efficient separation of electrons and holes. Moreover, Ndefect engineered tri-s-triazine units impart the lowest Gibbs free energy barrier of −0.129 eV for the reduction of H+ to adsorbed H, thereby serving as the catalytically active sites. Enlightened by theoretical results, the Ndefect engineered tri-s-triazine units were created via post oxidation of PCN in an electronic furnace. Such PCN with N defects offers an increased photocatalytic H2 generation under visible light exposure. The highest H2 generation rate is up to 98.1 μmol h−1, 3.8 times higher than that by using pristine PCN (26.1 μmol h−1). This work manifests the significance of localizing charge carriers close to the catalytically active sites for increased photocatalytic performance of PCN.
研究领域:
材料科学
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理论计算化学
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高影响因子
Journal of Energy Chemistry
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2021
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IF 9.676
Xiangang Lin,Haiwei Du,Daochuan Jiang,Peng Zhang,Zhiwu Yu,Hong Bi,Yupeng Yuan
The n-π* electronic transition in polymeric carbon nitride (PCN) can remarkably harvest visible light, which thus potentially promotes the photocatalytic hydrogen H 2 generation. However, awaking the n-π* electronic transition has proven to be a grand challenge. Herein, we reported on the awakening of n-π* electronic transition by microwave thermolysis of urea pellet, which yielded the PCN with absorption edge of 600 nm, near 140 nm red-shift from 460 nm of pristine PCN. The n-π* electronic transition endows PCN with an increased photocatalytic H 2 generation, with a highest H 2 rate of 61.7 μmol h −1 under visible light exposure, which is near 6 times higher than that by using the PCN from the thermolysis of urea pellets in an electric furnace (10.6 μmol h −1 ). Furthermore, the n-π* transition in PCN leads to the longest wavelength of 535 nm that can initiate H 2 generation, remarkably longer than the absorption edge of pristine PCN (460 nm). This work manifests the advantages of microwave sintering route to awaken the n-π* electronic transition in PCN for an increased photocatalytic performance.
研究领域:
材料科学
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能源化学
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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
Yan Chen,Yingpeng Cheng,Yue Liu,Yaqian Wang,Yi Qu,Daochuan Jiang,Zhaozhao Qin,Yupeng Yuan
The presence of short-lived shallow trapping states in semiconductor-based photocatalysts hinders efficient utilization of charge carrier, which compromises the solar-to-hydrogen efficiency. Here, we presented an engineered graphitic carbon nitride (g-CN) nanosheets with long-lived shallow trapping states achieved through an n-π * electronic transition. This transition induces a significant red-shifted absorption edge at 600 nm, effectively extending the range of light absorption compared to pristine g-CN. Moreover, the engineered g-CN nanosheets exhibit lower exciton binding energies (36 meV) compared to pristine counterparts (50.1 meV), as revealed by temperature-dependent photoluminescence (PL) spectra. Femtosecond transient absorption spectroscopy (fs-TAS) confirms the presence of long-lived shallow trapping states (lifetime: 565.8 ps) in the engineered g-CN nanosheets. These states enable a greater participation of photoinduced electrons in photocatalytic reactions, resulting in significantly enhanced photoactivity. Notably, the g-CN sample with the n-π * transition achieves a remarkable photocatalytic H 2 production rate of 61.8 µmol h −1 , which is a fivefold enhancement over pristine g-CN nanosheets. These findings highlight the crucial role of the n-π * transition in g-CN for prolonging shallow electron trapping and ultimately leading to superior photocatalytic performance.
研究领域:
材料科学
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能源化学
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DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
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2024
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IF 8.1
Xiangang Lin,Yan Ke,Yuan Liu,Xinglong Li,Zhiwu Yu,Daochuan Jiang,Yupeng Yuan
It is greatly desirable to simultaneously modulate the micromorphology and π-electrons of graphitic carbon nitride (GCN) to achieve highly photocatalytic hydrogen (H 2 ) evolution activity. Here, hexagonal hollow porous tubular GCN with rich-π-electrons (GCNT) was successfully fabricated via a simple self-assembly engineering coupled with a thermal polymerization approach. Compared with bulk GCN, incorporation of pyridine groups into the skeleton of GCNT not only significantly increased the specific surface area , exposed more active sites, and improved utilization of photons, but also expanded the π-electrons density, optimized the electronic band structure , promoted the rapid separation/migration of charge carriers. As a result, GCNT exhibited superior photocatalytic activity , with a H 2 evolution rate of 20.1μmol h −1 under visible light irradiation (λ > 420 nm), which was approximately 6.1 times higher than that of bulk GCN. The enhancement photocatalytic activity is ascribed to the hexagonal hollow porous tubular morphology and rich-π-electrons synergistic effect. The present study proposes a promising strategy for exploiting the highly efficient photocatalytic H 2 evolution of GCN by modulating microscopic morphology and π-electrons.
研究领域:
材料科学
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能源化学
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DOI
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
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2022
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IF 5.876
Wen Bo Zhu,Ling Gao,Yu Kang Zhang,Qi Zhang,Ying Hong,Wei Jian Shen,Ying Wang,Jian Hua Zhu
Liquid adsorption of TSNA by ZIF-8 was studied in this paper for the first time, applying the deformable molecular sieve to adsorb and separate TSNA. ZIF-8 can adsorb the bulky NNK molecules whose size exceeds its pore size, whereas NaA and KA zeolites cannot though they have similar pore sizes. Moreover, ZIF-8 selectively adsorbed NNK in solution and reached adsorption equilibrium within 5 min. In contrast, NNN was hard to be adsorbed and easy to be eluted by water, which is useful for the separation of TSNA. The influence of solid-liquid (S/L) ratio and other factors on TSNA liquid adsorption was investigated in detail. When S/L was 0.2, ZIF-8 exerted the highest efficiency and the adsorption capacity per unit surface area reached 12–15 nmol. Through the comparison of adsorption of NNK, NNN and NPYR, it is found that the adsorption of TSNA by ZIF-8 depended on π-π electron interaction mainly, rather than geometric confinement effect. The liquid adsorption curve of NNK conforms to Langmuir isothermal adsorption model, and its saturated adsorption capacity Q m was estimated to be 4.34 mg g −1 , but actually it could reach 3.19 mg g −1 only. In addition, ZIF-8 had a mixing effect in liquid adsorption of TSNA: the presence of NNK promoted the adsorption of NNN slightly. ZIF-8 has the characteristics of fast adsorption and easy elution of TSNA in solution, which is beneficial for removal of TSNA to protect the environment and public health.
研究领域:
环境科学
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公共卫生
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材料科学
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DOI
高影响因子
Journal of Materials Chemistry A
·
2025
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IF 9.5
Rou-Yu Li,Wenyu Yuan,Meng-Ru Cui,Boda Li,Hui Zhang,Zhenhao Peng,Quan-Guo Zhai
The interfaces in heterostructure photocatalysts play an important role in charge migration, but the rational controllable interfacial construction remains a challenge. Herein, a covalently bonded interface with delocalized π bonds was controllably constructed via the encapsulation of UiO-66-NH2 nanoparticles in MUV-10 skeletons. The UiO-66-NH2/MUV-10 heterojunction enabled both efficient capture and conversion of CO2 and H2O. The delocalized π bond in the covalent interface efficiently accelerated interfacial charge migration, suppressed carrier recombination, and reduced the work function for electronic effusion. As a consequence, UiO-66-NH2/MUV-10 exhibited superior CO2 photoreduction activity with H2O under visible light irradiation in the gas–solid phase. The CO evolution rate reached as high as 38.7 μmol g−1 h−1, which surpassed that of most commonly reported gas–solid phase photocatalysts. This work not only provides a feasible strategy for the controllable construction of interfaces but also demonstrates the great potential of interfacial engineering for efficient photocatalysis and other related areas.
研究领域:
材料科学
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催化化学
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DOI
高影响因子
CERAMICS INTERNATIONAL
·
2019
·
IF 3.45
Chunyan Su,Yazhou Zhou,Lili Zhang,Xiaohui Yu,Shuai Gao,Xiujuan Sun,Chao Cheng,Qinqin Liu,Juan Yang
Graphitic carbon nitride (g-C 3 N 4 ) has been demonstrated to be a rising star among semiconductor materials for photocatalytic hydrogen (H 2 ) production. However, pristine g-C 3 N 4 usually suffers from inferior activity due to the inadequate visible light harvesting capacity and quick charge recombination. Herein, porous P doped g-C 3 N 4 nanosheets (PCNNSs) were fabricated via a simple thermal condensation of adenosine phosphate and urea followed by thermal exfoliation method. The synergetic effect of the porous structure and P dopant can provide abundant active sites for the photocatalytic reaction, which can enhance light absorption range extending from 450 nm to 700 nm attributed to the n→π* electronic transition, and improve hydrophilicity for easier water molecules adsorption via introducing hydroxyl groups. Furthermore, impurity level caused by the P dopant would change the excitation process and accelerate the charge separation efficiency. Therefore, the PCNNSs exhibited significantly elevated photocatalytic H 2 generation performance (9523.7 μmolg -1 h -1 ) under visible-light (λ > 420 nm) irradiation, which was about 20 times that of unmodified g-C 3 N 4 (458 μmol -1 h -1 ).
研究领域:
材料科学
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能源化学
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DOI
高影响因子
TRIBOLOGY INTERNATIONAL
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2019
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IF 3.517
Mingjin Fan,Jia Ai,Chenghong Hu,Xin Du,Feng Zhou,Weimin Liu
In this paper, we present the synthesis and tribological properties of two naphthatate-based lubricating oils. The structure and purity of the oils were analyzed using nuclear magnetic resonance spectra and high resolution mass spectra. Their thermal and oxidation stability, flash point and pour point, viscosity and viscosity index, and friction reduction and anti-wear properties were also tested. In the results, the two isooctyl naphthatate-based oils (INA) displayed better lubricating properties than a reference sample of isooctyl sebacate (ISE) on three different friction pairs . The new oils also offered higher oxidation stability than the reference sample. It was found that the stability and lubrication properties of ester-based lubricating oils can be significantly improved by introducing a naphthalene ring into the molecular structure. This is because there is a large π-electron conjugate system on the naphthalene ring, which not only reduces the likelihood of an oxidation chain reaction, but also enables the oil to form an orderly and stable lubricating film on metal surfaces. One of the oils, 2,3-INA, was found have better oxidation stability than the other one, 1,4-INA, because its oxidized groups are positively affected by the steric and conjugation effects of the two ester groups.
研究领域:
化学工程
·
材料科学
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DOI
高影响因子
CATALYSIS LETTERS
·
2021
·Vol. 152
·期 3
·669-678
·
IF 3.186
Niu Ling,Du Jianmei,Jiang Daochuan,Du Haiwei,Lin Xiangang,Xu Jiahui,Li Zhongjun,Zhu Chuhong,Gu Lina,Bi Hong,Yuan Yupeng
Carbon defects in graphitic carbon nitride (g-CN) can modulate the electronic structure for efficient separation of electron–hole pairs, and thereby potentially enhance the photocatalytic H 2 generation. However, the mechanism on the separation of electrons and holes in C defect-modified g-CN still remains unclear. Here we report an autogenic ammonia gas route via in-situ urea decomposition to create carbon defects in g-CN for realizing increased photocatalytic H 2 generation rate of 36.62 µmol h −1 under visible light exposure, which is 10 times higher than that of g-CN obtained in the absence of autogenic ammonia gas (~ 3.63 µmol h −1 ). Illustrated by the density functional theory calculations, the C defects can not only reduce the band gap for increased light harvesting, but also delocalize the π electrons in valence band (VB) and conduction band (CB) for efficient charge transfer. Such delocalization of π electrons facilitates the efficient separation of electrons in LUMO and holes in HOMO, then promoting the photocatalytic H 2 generation. Therefore, the creation of C defects can be used as an effective route to delocalize the π electrons in g-CN for efficient photocatalytic H 2 generation. Graphical Abstract
研究领域:
材料科学
·
物理化学
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DOI
高影响因子
危险品化学品经营许可证（带存储）