INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2018
·
IF 3.141
Xianghong Li,Lei Li,Xiang Ren,Dan Wu,Yong Zhang,Hongmin Ma,Xu Sun,Bin Du,Qin Wei,Baihai Li
NH3 synthesis consumes 1% of the world’s energy, making it a substantial contribution to greenhouse gas emissions. Electrochemical artificial N2 fixation provides a green and sustainable route over the traditional Haber–Bosch process to enable sustainable NH3 synthesis at ambient conditions while requiring catalysts for the N2 reduction reaction (NRR). Here, we first demonstrate that the Y2O3 nanosheet serves as a high-efficiency nonprecious metal NRR catalyst. When tested at neutral pH, such Y2O3 nanosheet attains a large NH3 yield of 1.06 × 10–10 mol s–1 cm–2 and a high Faradaic efficiency of 2.53% at −0.9 V vs reversible hydrogen electrode with excellent stability and durability. Density functional theory calculations reveal that addition of the first H atom is the potential crucial step, the following hydrogenation steps are feasible, and it is easy to release NH3 molecules.
研究领域:
化学
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材料科学
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环境科学
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产品关联
DOI
高影响因子
Small Methods
·
2019
·Vol. 3
·期 12
·1900474
·
IF 0
Yongwen Ren,Chang Yu,Xinyi Tan,Xiaotong Han,Hongling Huang,Huawei Huang,Jieshan Qiu
The electrocatalytic N 2 reduction reaction (ENRR) to ammonia has attracted much attention due to the mild operating conditions, in which the Nafion membrane is generally adopted to separate the ammonia from the anode products. However, it has been mentioned that the Nafion membrane allows ammonia to pass through and traps the ammonia to some extent, but powerful confirmation experiments and effective solutions are still lacking. Herein, it is experimentally confirmed that the use of the Nafion membrane in the ENRR is inappropriate, based on the results that the ammonia can pass through the membrane, be adsorbed on the membrane, and interact with the membrane. This causes a measurement error and accelerates the membrane degradation process, which is unfavorable for ammonia quantification and the long-term stability operation of the ENRR in practical application. Also, for the first time, a more accurate method to evaluate the activity of the ENRR electrocatalyst using a salt bridge to replace the Nafion membrane is presented.
研究领域:
化学工程
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材料科学
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电化学
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DOI
ChemCatChem
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2018
·Vol. 10
·期 20
·4530-4535
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IF 4.674
Xiaojiao Xiang,Zao Wang,Xifeng Shi,Meikun Fan,Xuping Sun
Graphical Iron rods : here, Fe 2 O 3 nanorods are reported as an efficient non-noble-metal electrocatalyst for the nitrogen reduction reaction under ambient conditions. The nanorods efficiently catalyze N 2 to NH 3 in 0.1 M Na 2 SO 4 , achieving a Faradaic efficiency of 0.94 % with a NH 3 yield of 15.9 μg h −1 mg −1 cat. at a potential of −0.8 V vs. reversible hydrogen electrode. The conventional Haber-Bosch process for industrial ammonia production from N 2 and H 2 is not only energy-intensive but also releases a large amount of CO 2 . The electrocatalytic nitrogen reduction reaction (NRR) is regarded as a sustainable and environmentally-benign alternative approach for NH 3 production under ambient conditions. In this communication, it is reported that Fe 2 O 3 nanorods act as an efficient electrocatalyst for the NRR. In 0.1 M Na 2 SO 4 , it attains a Faradic efficiency of 0.94 % and NH 3 yield of 15.9 μg h −1 mg −1 cat. at −0.8 V vs. reversible hydrogen electrode. Furthermore, this catalyst also shows good stability during electrolysis and recycling tests.
研究领域:
化学
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环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
Advanced Science
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2018
·Vol. 6
·期 1
·1801182
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IF 12.441
Zao Wang,Feng Gong,Ling Zhang,Rui Wang,Lei Ji,Qian Liu,Yonglan Luo,Haoran Guo,Yuehui Li,Peng Gao,Xifeng Shi,Baihai Li,Bo Tang,Xuping Sun
NH 3 is a valuable chemical with a wide range of applications, but the conventional Haber–Bosch process for industrial-scale NH 3 production is highly energy-intensive with serious greenhouse gas emission. Electrochemical reduction offers an environmentally benign and sustainable route to convert N 2 to NH 3 at ambient conditions, but its efficiency depends greatly on identifying earth-abundant catalysts with high activity for the N 2 reduction reaction. Here, it is reported that MnO particles act as a highly active catalyst for electrocatalytic hydrogenation of N 2 to NH 3 with excellent selectivity. In 0.1 m Na 2 SO 4 , this catalyst achieves a high Faradaic efficiency up to 8.02% and a NH 3 yield of 1.11 × 10 −10 mol s −1 cm −2 at −0.39 V versus reversible hydrogen electrode, with great electrochemical and structural stability. On the basis of density functional theory calculations, MnO (200) surface has a smaller adsorption energy toward N than that of H with the *N 2 → *N 2 H transformation being the potential-determining step in the nitrogen reduction reaction.
研究领域:
材料科学
·
催化化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Small
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2023
·
IF 13.3
Jian Song,Xue Lei,Jiali Mu,Jingwei Li,Xiangen Song,Li Yan,Yunjie Ding
Heteroatom-doping is an effective method for modifying the geometric symmetry of metal–nitrogen–carbon (M–N–C) single-atom catalysts and thereby tuning the electronic structure. Up to now, most of the current reports have concentrated on introducing heteroatoms into the highly symmetrical M–N 4 structure. The coordination-unsaturated M–N 2 structure is more sterically favorable for the insertion of alien atoms to optimize the electronic structure. Herein, a Ni–N 2 catalyst with out-of-plane coordinated chlorine (Cl) atoms (Ni–N 2 Cl/C) is successfully constructed on chlorine-functionalized carbon supports (C–Cl) for an efficient carbon dioxide reduction reaction (CO 2 RR). Density functional theory calculations demonstrate that the prepared Ni–N 2 Cl/C catalyst exhibits a higher capability in balancing COOH* formation and CO* desorption. In addition, in situ Raman spectra confirm that the lower CO binding energy on the Ni–N 2 Cl/C facilitates CO escape, leading to excellent CO 2 RR performance. A high CO Faradaic efficiency (FE CO ) of more than 80% is achieved from −0.6 to −1.2 V versus reversible hydrogen electrode on the Ni–N 2 Cl/C and it exhibits negligible FE CO and current declination over a 40-h stability test. Furthermore, a high turnover frequency (TOF) value of 15 808 h −1 is obtained, which is more than ten times that of Ni–N 2 /C (1476 h −1 ) without coordinated Cl atoms.
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产品关联
DOI
PubMed
高影响因子
Tungsten
·
2023
·
IF 6.6
Yang Meng-Le,Jin Zhong-Xin,Cao Xi-Xian,Wang Xin-Ming,Ma Hui-Yuan,Pang Hai-Jun,Yang Gui-Xin
Accelerating the breaking of the nitrogen nonpolar bond (N≡N) is an important factor to improve the efficiency of the electro-catalytic nitrogen reduction reaction (e-NRR). In this work, polyoxometalates-derived FeMo-based ternary oxide materials MoO 2 -Mo 4 O 11 -FeMoO 4 @ X (abbreviated as MoFeO@ X , X represents the synthesis temperature of 650, 750 and 850 °C) were designed and synthesized for e-NRR under ambient conditions. The scanning electron microscopy images of MoFeO@750 show an ellipsoidal-like structure (0.86 × 0.6 μm). The relatively large specific surface area, formation of multiple interfaces, together with the synergistic effect of iron and molybdenum bimetals, would make MoFeO@ X catalyst more easily absorb and activate N 2 in the e-NRR. Expectedly, the synthesized MoFeO@750 shows an optimal NH 3 production rate of 16.57 μg·h −1 ·mg cat. −1 and Faradaic efficiency of 12.33% at − 0.3 V versus reversible hydrogen electrode (νs. RHE), with outstanding electrochemical and structural stability.
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产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
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2023
·
IF 7.2
Hui Zhang,Qiang Fu,Hongyun Qin,Xia Chen,Qicheng Zhang,Zixu Dong,Haoyuan Li,Shoudong Wang,Ming Wang
Hydrogen recovery from ammonia purge gas is a desirable method to relieve the pressure of increasing demand for hydrogen. Metal-organic frameworks (MOFs) are promising adsorbents for the separation of the H 2 –N 2 mixture. However, the separation of the H 2 –N 2 mixture using MOFs remains challenging due to the lack of adsorptive mechanism. Herein, the adsorption mechanism of the H 2 –N 2 mixture in SIFSIX-2-Cu-i has been systematically investigated with the method of a combination of excess adsorption experiments, molecular simulations , and DFT calculations. In the Grand Canonical Monte Carlo (GCMC) simulations, the polarizable force field was first applied to the adsorption of pure H 2 or N 2 and H 2 –N 2 mixture in SIFSIX-2-Cu-i. Ab Initio Molecular Dynamics (AIMD) was performed to investigate the distribution of the guest molecules in the pores of SIFSIX-2-Cu-i. Finally, Density functional theory (DFT) calculations were performed to predict the transfer of charge between MOF and guest molecules. Results revealed two binding sites of H 2 or N 2 in SIFSIX-2-Cu-i. A relatively high thermodynamic adsorption selectivity for N 2 over H 2 has been observed in SIFSIX-2-Cu-i. Furthermore, SIFSIX-2-Cu-i also exhibits a greater affinity with N 2 than with H 2 , which is probably because of the stronger induction interactions between F2 atoms and N 2 molecules. These findings are of significance to guide the design of the new highly selective adsorbents for the separation of H 2 /N 2 .
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DOI
高影响因子
ACS Applied Energy Materials
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2020
·
IF 4.473
Huijuan Han,Yang Yang,Jiafang Liu,Xiuzhen Zheng,Xulin Wang,Sugang Meng,Sujuan Zhang,Xianliang Fu,Shifu Chen
Photocatalytic nitrogen fixation is considered as a very promising technology to solve the high-energy consumption problem in industrial ammonia synthesis. Because of the mildness of reaction conditions, its development is still limited by the low reaction efficiency and unknown reaction mechanism. Inspired by the mechanism of biological nitrogen fixation in nature, Zn3In2S6 with different sulfur sources is prepared to study the effects of cation defects on the adsorption, activation, and reaction in photocatalytic nitrogen fixation. Because of the electron-rich property of zinc vacancies in Zn3In2S6 nanosheets, it can effectively activate the N≡N triple bond, thereby increasing the rate of kinetic reduction. With the activation of N2 molecules on zinc vacancies, the existing protons obtained from methanol (solvent) will greatly accelerate the electron transfer between interfaces during the nitrogen reduction reaction. Notably, Zn3In2S6 with rich Zn vacancies exhibits higher activity (355.2 mg L–1 gcat–1, 15 times) than Zn3In2S6 with poor vacancies in nitrogen fixation. This work describes the contribution of zinc vacancies to the fixation and activation of nitrogen molecules, which is very important to establish a highly effective system of photocatalytic nitrogen fixation.
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产品关联
DOI
高影响因子
REACTIVE & FUNCTIONAL POLYMERS
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2021
·
IF 3.975
Hui Wang,Yunxia Ni,Zhiyue Dong,Qiang Zhao
Interface compatibility is crucial to performance and robustness of nanocomposite membranes for molecular separation. In this work, a covalent crosslinking method was exploited to fabricate polydimethylsiloxane/metal-organic-frameworks (PDMS/MOFs) mixed matrix membranes with improved interfacial compatibility. Zirconium MOF particles (UiO-66-NH 2 ) were grafted with methoxysilane groups, which further formed covalent crosslinks with silanol terminated PDMS matrix. The strengthened interfacial compatibility prevented sedimentation and aggregation of MOF particles in PDMS precursor solution during the solvent evaporation process, thus the composites showed good membrane formation ability at high MOFs loading (60 wt%). Tensile strength of the hybrid membrane is 2.8 times improved while retaining good flexibility. Moreover, the CO 2 /N 2 selectivity and CO 2 permeability of the PDMS composite membrane incorporated with 40 wt% UiO-66-MS particles are improved by 1.3 times and 0.7 times, respectively.
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产品关联
DOI
高影响因子
ChemSusChem
·
2024
·
IF 7.5
Lixinyu Wang,Shangwen Zha,Shenxiang Zhang,Jian Jin
Graphical A highly stable, CO 2 facilated transport membrane that can operate at simulated flue gas conditions with temperature up to 90 °C and high humidity is reported. The mobile amine-carriers for CO 2 were stablized within the sulfonated chitosan ion gel membrane. By virtue of carrier-facilitated transport, high CO 2 permeance (as high as 1155 GPU) and ultrahigh CO 2 /N 2 selectivity (above 550) were achieved. Capturing carbon dioxide (CO 2 ) from flue gases is a crucial step towards reducing CO 2 emissions. Among the various carbon capture methods, facilitated transport membranes (FTMs) have emerged as a promising technology for CO 2 capture owing to their high efficiency and low energy consumption in separating CO 2 . However, FTMs still face the challenge of losing mobile carriers due to weak interaction between the carriers and membrane matrix. Herein, we report a sulfonated chitosan (SCS) gel membrane with confined amine carriers for effective CO 2 capture. In this structure, diethylenetriamine (DETA) as a CO 2 -mobile carrier is confined within the SCS gel membrane via electrostatic forces, which can react reversibly with CO 2 and thus greatly facilitate its transport. The SCS ion gel membrane allows for the fast diffusion of amine carriers within it while blocking the diffusion of nonreactive gases, like N 2 . Thus, the prepared membrane exhibits exceptional CO 2 separation capabilities when tested under simulated flue gas conditions with CO 2 permeance of 1155 GPU and an ultra-high CO 2 /N 2 selectivity of above 550. Moreover, the membrane retains a stable separation performance during the 170 h continuous test. The excellent CO 2 separation performance demonstrates the high potential of gel membranes for CO 2 capture from flue gas.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Junfei Chen,Zhihao Yu,Jinwei Wu,Zhao-Bin Ding,Lin Lang,Lining Fang,Xiuli Yin,Zebao Rui
Selective catalytic oxidation of ammonia (NH 3 -SCO) is considered an efficient and environmentally friendly technology to remove trace ammonia pollutants. The Cu-based and Ag-based catalysts have been taken as among the most promising choices for NH 3 -SCO. However, the insufficient NH 3 catalytic activity of Cu-based catalysts and poor N 2 selectivity of Ag-based catalysts restrict their commercial applications. Herein, we report a facile stepwise induced loading method to obtain anatase titania-supported Cu-Ag composite catalysts with well Cu-Ag nanoparticles dispersion and interaction. The enhanced dispersion of Cu-Ag nanoparticles promotes their interaction with TiO 2 support, improves the stability and reducibility of active sites, and finally leads to appropriate chemical states and synergy of the Cu-Ag complex active sites for improving NH 3 conversion and N 2 selectivity. The as-designed CuO x /AgO y /TiO 2 shows outstanding NH 3 -SCO low-temperature catalytic performance with a (>)99 % NH 3 conversion and 83 % N 2 selectivity under 12000 mL g -1 h −1 at 175 °C as well as satisfied long-term stability.
研究领域:
环境科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY
·
2018
·
IF 4.841
Yongheng Xiong,Yiqing Zeng,Wei Cai,Shule Zhang,Jie Ding,Qin Zhong
The effects of various factors on the NO removal activity in the (NH 4 ) 2 SO 3 solution were investigated to explore more details and characteristics of the related reactions using full infrared sensor flue gas analyzer (FISFGA). It was found that the conversion yield of NO (9.0%–29.0%) was obviously improved with the increase of gas–liquid contact area, NO residence time and (NH 4 ) 2 SO 3 concentration as well as the adding of CuSO 4 . However, it was mainly limited by gas–liquid mass transfer rate and slightly inhibited by the gas velocity. Moreover, the FISFGA analysis revealed that two nitric oxide (NO) conversion route with different reduction product of N 2 O and N 2 existed simultaneously upon the existence form of SO 3 2− . It was confirmed by the calculations and the experiments of pH factor that the NO reduction steps were based on the following equation: (1) NO + HSO 3 − ⇋ N 2 O + SO 4 2− + H + ; (2) NO + SO 3 2− ⇋ N 2 + SO 4 2− . In this system, Eq. (1) with N 2 O product was the major pathway, but the ratio of Eqs. (2) to (1) was intensified in the presence of CuSO 4 . It is believed that the suitable additives could promote the NO reduction to N 2 furtherly.
研究领域:
环境科学
·
化学工程
✓ 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）