Science Bulletin
·
2019
·
IF 6.277
Xiang Gao,Li An,Dan Qu,Wenshuai Jiang,Yanxiao Chai,Shaorui Sun,Xingyuan Liu,Zaicheng Sun
Photocatalytic N 2 fixation involves a nitrogen reduction reaction on the surface of the photocatalyst to convert N 2 into ammonia. Currently, the adsorption of N 2 is the limiting step for the N 2 reduction reaction on the surface of the catalyst. Based on the concept of photocatalytic water splitting, the photocatalytic efficiency can be greatly enhanced by introducing a co-catalyst. In this report, we proposed a new strategy, namely, the loading of a NiS co-catalyst on CdS nanorods for photocatalytic N 2 fixation. Theoretical calculation results indicated that N 2 was effectively adsorbed onto the NiS/CdS surface. Temperature programmed desorption studies confirmed that the N 2 molecules preferred to adsorb onto the NiS/CdS surface. Linear sweep voltammetry results revealed that the overpotential of the N 2 reduction reaction was reduced by loading NiS. Furthermore, transient photocurrent and electrochemical impedance spectroscopy indicated that the charge separation was enhanced by introducing NiS. Photocatalytic N 2 fixation was carried out in the presence of the catalyst dispersed in water without any sacrificial agent . As a result, 1.0 wt% NiS/CdS achieved an ammonia production rate of 2.8 and 1.7 mg L −1 for the first hour under full spectrum and visible light ( λ > 420 nm), respectively. The catalyst demonstrated apparent quantum efficiencies of 0.76%, 0.39% and 0.09% at 420, 475 and 520 nm, respectively. This study provides a new method to promote the photocatalytic efficiency of N 2 fixation.
研究领域:
材料科学
·
环境科学
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DOI
PubMed
高影响因子
CRYSTENGCOMM
·
2015
·Vol. 17
·期 19
·3677-3686
·
IF 4.034
Guohai Xu,Min Xie,Xiaokang Li,Wenjie Shi,Hui Yu,Yinhui Hu,Xiaochen Xun,Yongrong Xie
In this work, crystal engineering is focused on the self-assembly of 2D 63 topology into different supramolecular networks using unit–unit H-bonds. Four related coordination polymers, [Zn2(teaH2)(ndc)1.5]·MeOH (1), [Co2(teaH2)(ndc)1.5]·MeOH (2), [Zn2(deaH)(ndc)1.5]·MeOH (3) and [Co2(teaH2)(btb)]·3EtOH (4) where ndc2− = 2,6-naphthalenedicarboxylate, btb3− = benzene-1,3,5-tribenzoate, teaH3 = triethanolamine, and deaH2 = diethanolamine, contain a well-known 63 subnet and the binuclear units. Furthermore, their 63 nets present different hexagonal windows (chair- or ship-shaped) and diversified layer arrays (ABAB or ABCABC sequence). The 63 subnet and symmetry-related unit–unit H-bonds as supramolecular synthons can build up different supramolecular networks. Compounds 1 and 2 show a distorted diamond supramolecular network due to formation of a square-pyramidal node. Because the formation of a seesaw-shaped node, compound 3 features a general diamond supramolecular network with 3-fold interpenetration. Compound 4 exhibits a binodal supramolecular framework in that H-bonding interactions occur between three binuclear units. In addition, the diversified layer array has endowed compound 4 with a large 1D channel, which can be characterized by standard N2 adsorptions. Compound 4 has a type I adsorption isotherm with an appreciable adsorption of 45.04 cm3 g−1 at 0.40 P/P0, whereas 1–3 do not exhibit appreciable N2 uptake.
研究领域:
化学
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材料科学
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产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2023
·
IF 8.6
Xuan Tang,Yugao Wang,Mengni Wei,Xueqin Zhang,Ye Li,Xiaomin Li,Jinping Li,Jiangfeng Yang
Reduction of zeolite crystal size from the micron scale to the nanoscale leads to a significant increase in specific surface area, favoring mass-transfer pathways. Here, we have prepared nanoscale (ca. 30–80 nm) IM-5@100 zeolite (IMF type) by a facile strategy of regulating the amount of Al source in the starting gel, and have investigated its CH 4 /N 2 adsorption and separation properties. We found that on decreasing the amount of Al source, the crystal size of the product changed significantly, decreasing from strips of length about 1 μm to irregular nanocrystals. Compared with micron-sized IM-5@50, the mesopore volume of IM-5@100 was increased fourfold from 0.12 cm 3 /g to 0.49 cm 3 /g, its external surface area was increased from 38 m 2 /g to 118 m 2 /g, and its DFT pore size distribution based on N 2 adsorption/desorption showed a mesopore distribution in the range 5–10 nm. Adsorption kinetics tests showed that nano-IM-5@100 can achieve adsorption equilibrium more swiftly and exhibits better mass-transfer performance. Moreover, IM-5@100 showed good adsorption capacity for CH 4 (17.8 cm 3 /g) and high IAST selectivity (4.7) for CH 4 /N 2 (50:50, v/v). Breakthrough experiments have indicated that IM-5@100 permits efficient practical separation of CH 4 /N 2 .
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
ENERGY
·
2022
·
IF 8.857
Yangfeng Zheng,Cheng Zhai,Aikun Chen,Xu Yu,Jizhao Xu,Yong Sun,Yuzhou Cong,Wei Tang,Xinyu Zhu,Yujie Li
The intrusion of fracturing fluid into coalbed methane (CBM) reservoirs changes the microstructure of coal and affects CBM recovery. To study the microstructural evolution characteristics of bituminite and anthracite modified by different fracturing fluids, we prepared pure water (F1), slickwater (F2), and CO 2 foam fracturing fluids (F3) to treat coals, and low-temperature N 2 adsorption (LT-N 2 A), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD) tests were conducted to characterize the variation in the microscopic pore structure, functional group structure, and mineral components of the modified coals, respectively. The results show that different fracturing fluids can significantly change the pore structure characteristics of bituminite and anthracite . The pore volume of bituminite and anthracite modified by F1, F2, and F3 decreases successively, while the average pore size and the percentage of macropore (>50 nm) volume increase. The average pore sizes of bituminite and anthracite modified by F3 are 16.78 nm and 19.38 nm, respectively, which increase by 18.59% and 30.89% compared with that of bituminite modified by F2 and F1, respectively; the average pore sizes of anthracite increases by 3.20% and 332.47%, respectively. The pore fractal dimension of coal was calculated based on the low-temperature N 2 adsorption curve. It is found that the seepage pore fractal dimension ( D 1 ) of both bituminite and anthracite modified by F2 and F3 is smaller than that of F1 modification, with D 1 of F2 modified coals being the smallest. Therefore, F2 and F3 can make the seepage pores of coal smoother and reduce the complexity. F2 and F3 can reduce the aromaticity ( I ) and the degree of condensation of aromatic rings ( DOC ) of bituminite and anthracite and increase the structural parameter of the oxygen-containing functional groups ( ‘C’ ). The three fracturing fluids have little effect on the aliphatic chain length ( L ). F2 and F3 can dissolve the carbonate and clay minerals of coal to generate new pores to increase porosity and permeability. The results provide theoretical guidance for the fracturing of medium- and high-rank CBM reservoirs.
研究领域:
地质学
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能源科学
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产品关联
DOI
高影响因子
JOURNAL OF CLUSTER SCIENCE
·
2019
·Vol. 31
·期 2
·513-522
·
IF 2.125
Liu Qiang,Liu Yuqi,Zhang Qingqing,Wang Xinying,Li Wei
A new Pr(III)-based metal organic framework with formula {[Pr 2 (C 8 H 3 O 6 N)(SO 4 ) 2 ]·5H 2 O} n was hydrothermally synthesized and characterized by techniques of single crystal X-ray diffraction, infrared spectra (IR), thermogravimetric analysis (TGA), elemental analysis, powder X-ray diffraction (PXRD), and luminescent measurements. X-ray crystal structure analyses reveal that complex 1 is binuclear structure and all Pr(III) atoms show a coordination number of nine with a tricapped trigonal prismatic coordination geometry. Throughout the molecular structure, this lanthanide metal–organic frameworks exhibits a 3D architecture built by the 1D double-stranded chains of Pr ions linked by the 5-nitroisophthalic acid ligand and 2D Pr–SO 4 2− grid. In addition, the fluorescence, nitrogen adsorption properties and carbon dioxide adsorption properties of complex 1 were also investigated. The results indicate that the complex is not only a luminescent and mesoporous material, but also a potential material for selective absorption of carbon dioxide.
研究领域:
材料科学
·
化学
✓ 已验证
DOI
高影响因子
CHEMICAL RESEARCH IN CHINESE UNIVERSITIES
·
2024
·Vol. 40
·期 6
·1192-1200
·
IF 3.1
Huang Yitong,Wang Yaquan,Liu Wenrong,Bu Lingzhen,Qu Liping,Chu Kailiang,Guo Niandong,Zhang Xian,Su Xuemei,Li Yaoning,Sang Juncai
A series of low silica X zeolites (LSX) was synthesized through a seed-iteration approach, based on the seed addition strategy, and then loaded with lithium ions by an ion exchanging method to obtain high N 2 adsorption capacity. These zeolites were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectra (FTIR), thermogravimetric analysis (TGA) and N 2 adsorption-desorption, and the adsorption capacity of N 2 and O 2 was evaluated by the vacuum pressure swing adsorption (VPSA) operation. The results showed that the nucleation period of the synthetic process could be effectively shortened by adding seed; as the seed iterations increased, the specific surface area and pore volume of the zeolites increased; the higher specific surface area and the pore volume, the higher the extent of the N 2 adsorption capacity, with the maximum reaching 28.05 cm 3 /g. However, there were no significant differences in the adsorbed capacity of O 2 by each sample. Therefore, the N 2 /O 2 separation factor also increased gradually with iterations, with the maximum up to 6.61.
研究领域:
材料科学
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化学工程
·
吸附技术
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2025
·
IF 6.9
Mingliang Sun,Ao Sun,Hongwei Zhu,Ruyu Zhang,Xiaowei Jia,Yan Xing
Photocatalytic nitrogen fixation provides a sustainable alternative to the energy-intensive Haber–Bosch process, yet its efficiency is limited by poor N 2 solubility, weak adsorption, rapid charge recombination, and competing hydrogen evolution. reaction (HER). In this work, we introduce a synergistic interfacial strategy integrating Schottky junction construction and hydrophobic surface engineering to enhance photocatalytic N 2 fixation. Bi nanoparticles are in-situ anchored onto Bi 3 TiNbO 9 (BTNO) to construct Bi/BTNO Schottky junctions, facilitating directional electron transfer and accumulation at Bi active sites. Concurrently, surface hydrophobicity of Bi/BTNO is precisely tailored via 1-dodecanethiol modification, promoting N 2 enrichment at the reaction interface while effectively suppressing HER. The optimized 2C 12 S-1 % Bi/BTNO catalyst achieves an exceptional ammonia production rate of 25.83 μmol g -1 h −1 in pure water without sacrificial agents, outperforming pristine BTNO by 6.96-fold and unmodified Bi/BTNO by 2.85-fold. Photoelectrochemical measurements and in situ FTIR spectroscopy verify enhanced charge separation and an associative distal pathway for N 2 reduction. This work underscores the importance of interface microenvironment design in addressing kinetic and selectivity limitations, offering a versatile platform for efficient solar-driven nitrogen fixation.
研究领域:
材料科学
·
光催化
·
环境能源化学
·
纳米催化
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表面科学
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2013
·
IF 2.206
Jiangfeng Yang,Junmin Li,Wei Wang,Libo Li,Jinping Li
Three hydrophobic microporous high-silica zeolites, DDR (with an 8-membered ring), silicalite-1 (a 10-membered ring), and beta (a 12-membered ring) were synthesized. The Si/Al ratios were 230, 1350, and 35, respectively. The samples were characterized by X-ray diffraction, scanning electron microscopy, thermal gravimetric analysis, water vapor adsorption, and volumetric nitrogen adsorption. They were tested for their CO2, CH4, and N2 adsorption properties at pressures of up to 10 bar at 288–313 K after activation, and the results were correlated with the Langmuir model. The heat of adsorption was calculated using the Clausius–Clapeyron equation based on the adsorption isotherms. These data were used to estimate the separation selectivities for CO2/CH4 and CH4/N2 binary mixtures at 298 K, using the ideal adsorbed solution theory (IAST) model. Experimental results showed that DDR and beta have good selectivities for CO2/CH4, because they have narrow pores (DDR) or more balance metal ions (relatively low Si/Al ratios beta) effect separately. The synthesized silicalite-1 has the lowest SCO2/CH4 but has the most suitable orifices for methane adsorption and the highest SCH4/N2. In addition, the breakthrough data for CH4/N2 mixtures further indicates that silicalite-1 is more suitable for the CH4 enrichment than the commercially used sorbents zeolite-5A and 13X. From the reproducibility of CH4 and N2 adsorption isotherms on silicalite-1, we can infer that which has the potential to be a commercial sorbent by the stable adsorption properties.
研究领域:
材料科学
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化学工程
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2016
·Vol. 40
·期 10
·8324-8333
·
IF 3.277
Xiong Wang,Renwei Xu,Bochao Zhu,Yanfeng Li,Yanping Ma
Functional porous organic polymers (POPs) {poly(2-hydroxyethylmethylacrylate-co-divinylbenzene) [P(HEMA-co-DVB)]} with different pore structures and morphology were prepared via a dispersion polymerization strategy. The effect of different solvent types, different ethanol/H2O volume ratios in the mixture solvent, and the (HEMA)/DVB molar ratio on the specific surface area and porosity was investigated. Non-local density functional theory (NLDFT) simulation based on nitrogen sorption porosimetry and scanning electron microscopy (SEM) were used to study the pore structure and morphology of the prepared P(HEMA-co-DVB) particles. The results showed a trend that P(HEMA-co-DVB) particles with a higher specific surface area and a lower average pore diameter were obtained in ethanol/deionized water mixture solvents with better thermodynamic compatibility; however, when different types of solvents were used, a higher average pore diameter (14.5 nm) and total pore volume (0.923 cm3 g−1) were achieved in a good thermodynamically compatible solvent–ethyl acetate. The HEMA functional comonomer could also be a good pore-adjuster that provides a feasible route to prepare functionalized PDVB particles with controllable pore structure and particle morphology. In the ethylene homopolymerization evaluation of supported metallocene catalysts, these nanoporous polymer supports reveal better catalytic activity compared with silica used as the metallocene support, exhibiting great potential for future applications in the polyolefin catalysis industry.
研究领域:
材料科学
·
催化化学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF POROUS MATERIALS
·
2016
·Vol. 24
·期 2
·291-296
·
IF 1.385
Sun Huaming,Lin Dezhi,Gao Ziwei
Novel graphene oxide layered hybrid framework materials pillared titanocene organometallic complex were prepared through a facile ultrasound intercalation approach. The products exhibited periodic layered structures with expanded interlayer spacing as characterized by XRD. Raman spectroscopy demonstrated that the skeleton structure of layered carbon still remained after titanocene treatment. Nitrogen sorption analysis indicated that the building blocks of graphene oxide sheets were cross-linked with titanocene molecules to form lamellar porous structures.
研究领域:
材料科学
·
纳米技术
·
化学
✓ 已验证
产品关联
DOI
高影响因子
Advanced Energy Materials
·
2025
·
IF 26
Xingzhi Zhu,Xiaoyun Miao,Chu Chen,Xiaofeng Ye,Yucun Zhou,Zhaoyin Wen
Protonic Ceramic Electrolysis Cells (PCECs) enable the in situ production of hydrogen and protons via steam electrolysis, positioning them as promising reactors for environmentally friendly ammonia synthesis. However, the efficiency and stability of this process are currently constrained by the limited catalysis activity and the aggregation of conventional fuel electrodes. Herein, in situ formed Fe-Co-Ni alloy nanoparticle catalysts are designed, and find that these alloy sites significantly enhance N 2 adsorption. Selective impregnation of Fe-Co and Ni exsolution is integrate to promote the in situ formation of Fe-Co-Ni alloy catalytic sites within the fuel electrode of tubular PCECs (10 cm 2 active area). Under an applied voltage of 0.6 V, the in situ alloyed PCEC reactor reaches 2.37 × 10 −8 mol s −1 NH 3 synthesis rate at 600 °C, which is 2.1 times that of with common fuel electrode. Density functional theory calculations further reveal that alloying reduces the activation energy for nitrogen hydrogenation, thereby facilitating the reaction pathway. Moreover, the in situ formed alloy sites exhibit a strong anchoring effect, effectively preventing catalyst aggregation at high temperature and enabling stable, efficient ammonia synthesis over 250 h. This study demonstrates the significant potential of in situ alloy catalysts combined with tubular PCECs for electrochemical ammonia synthesis.
研究领域:
电化学
·
材料科学
·
能源工程
·
催化
·
可持续化学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2017
·
IF 3.582
Yinghui Sun,Guojie Zhang,Jiwei Liu,Peiyu Zhao,Peng Hou,Ying Xu,Riguang Zhang
CH 4 CO 2 reforming to syngas was investigated over three different activated carbon catalysts. To better understand the influence of the supports on the catalytic properties , catalysts were analyzed by some characterization methods, such as nitrogen adsorption–desorption isotherms, XRD , H 2 -TPR, NH 3 -TPD, CO 2 -TPD, FTIR, TEM and EDX . The results showed that the catalyst with AC 2 as the support provided the best catalytic activity . The CH 4 conversion and CO 2 conversion were 92% and 98% at 900 °C, respectively; best selectivity with the H 2 /CO ratio was close to 1 among the three supports used. It also showed a better stability at 900 °C. H 2 -TPR analysis showed that Co species in Co/AC 2 catalyst were strong interaction with the support. It was observed that active metals were well dispersed on the AC 2 support by the TEM. In addition, the ratio of CH 4 /CO 2 also had great influence on the CH 4 and CO 2 conversion.
研究领域:
催化
·
化学工程
·
材料科学
✓ 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）