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
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环境科学
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DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2025
·
IF 9
Zewen Xu,Pei Li,Hao Guo,Shengchao Zhao,Kuo Chen,Xinliang Liu,Ming Wang,Yingfei Hou
Excessive carbon emission leads to global warming, threatening human survival. Membrane-based carbon capture technology is an important component of carbon capture, utilization, and storage (CCUS) technology and one of the main upstream technologies for achieving carbon neutrality. PIM-1 materials exhibit high CO 2 permeability but lower CO 2 /N 2 selectivity, making it a significant focus to improve CO 2 /N 2 selectivity without sacrificing CO 2 permeability. In this work, Noria was introduced as a block through the bottom-up approach into the PIM-1 molecular chain, forming Noria-based porous organic polymer (NPOP) microregions with excellent CO 2 affinity. Additionally, the presence of NPOP increases the interchain gaps, resulting in a higher free volume. Consequently, the separation membrane prepared under optimal conditions broke the 2008 upper bound, with a 43.6 % increase in CO 2 permeability and a 41.7 % increase in CO 2 /N 2 selectivity. Furthermore, NPOP could form colloidal networks and provide rigidity to the separation membrane, endowing it with excellent aging resistance. After 6 months of aging, the CO 2 permeability of 0.5 %Noria decreased by only 33.4 % (67.4 % for pure PIM-1), indicating its strong potential for widespread applications.
研究领域:
材料科学
·
环境科学
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DOI
高影响因子
Membranes
·
2023
·Vol. 13
·期 9
·781
·
IF 4.2
Jiaming Gao,Yongchao Sun,Feifei Kang,Fei Guo,Gaohong He,Hanli Wang,Zhendong Yang,Canghai Ma,Xiaobin Jiang,Wu Xiao
Mixed matrix membranes (MMMs) generally have some fatal defects, such as poor compatibility between the two phases leading to non-selective pores. In this work, PIM-1 was chosen as the polymer matrix, and UiO-66 modified with amidoxime (UiO-66-AO) was used as the filler to prepare the MMMs. In the MMMs, the amino and hydroxyl groups on UO-66-AO form a rich hydrogen bond network with the N and O atoms in the polymer PIM-1 chain to improve the compatibility between the polymer matrix and the filler. In addition, the selective adsorption of CO2by the amidoxime group can promote the transport of CO2in the membrane, which enhances the gas selectivity. The CO2permeability and CO2/N2selectivity of UiO-66-AO@PIM-1 MMMs are increased by 35.2% and 45.2% compared to pure PIM-1 membranes, reaching 7535.5 Barrer and 26.9, surpassing the Robeson Upper Bound (2008) and close to the 2019 Upper Bound. After 38 days of the aging experiment, the CO2permeability is approximately 74% of the original. The results show that the addition of UiO-66-AO has an obvious effect on improving the aging properties of the membrane. The UiO-66-AO@PIM-1 MMMs have a bright prospect for CO2separation in the future.Keywords:amidoxime;UiO-66-AO;mixed matrix membrane;PIM-1;CO2/N2separation
研究领域:
材料科学
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化学工程
·
环境科学
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DOI
PubMed
高影响因子
Journal of Environmental Chemical Engineering
·
2026
·Vol. 14
·期 5
·124243
·
IF 7.5
Yuanyuan Xu,Yunhua Lu,Pengwei Lv,Guoyong Xiao,Tonghua Wang,Lin Li
Interfacial defects between fillers and polymer matrix restrict the separation performance of mixed matrix membranes (MMMs). Herein, low-order polyimide (PI)-based covalent organic frameworks (COFs) fabricated from 2,4,6-tris(4-aminophenyl)-1,3,5-triazine (TAPT) and pyromellitic dianhydride (PMDA) were firstly adopted as fillers to modify thermally rearranged (TR) membranes. Distinct from highly crystalline COFs, low-order PI-COFs contain more exposed terminal reactive groups. These functional groups can form covalent linkages with poly(amic acid) precursors, which effectively suppresses the generation of non-selective interfacial voids and improves the interfacial compatibility between filler and polymer matrix. The hierarchical pores of PI-COFs construct low-resistance gas transport pathways, and triazine/imide polar sites deliver strong affinity for CO 2 . After thermal rearrangement at 450 °C, TR/COFs-2.3 achieves drastically boosted permeabilities: 4632 Barrer (CO 2 ), 3867 Barrer (H 2 ), 795 Barrer (O 2 ) and 215 Barrer (N 2 ). Its CO 2 /N 2 selectivity slightly increases to 21.54, while O 2 /N 2 and H 2 /N 2 selectivities moderately decline to 3.70 and 17.99. This membrane exceeds the 2008 Robeson upper bound for H 2 /N 2 , and nearly reaches the limit for CO 2 /N 2 and O 2 /N 2 . It also displays improved long-term aging stability (66–74% permeability retention after 180 days, versus 52% for neat TR membrane) and stable performance in a 6-day continuous mixed-gas test. This work proposes a low-order COF interfacial modification strategy to alleviate interfacial defects, providing a practical route to prepare high-performance TR-based MMMs.
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高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2022
·
IF 24.319
Shaomian Liu,Wenjuan Xue,Yongjun Ji,Wenqing Xu,Wenxing Chen,Lihua Jia,Tingyu Zhu,Ziyi Zhong,Guangwen Xu,Donghai Mei,Fabing Su
Simultaneously improving both NO x conversion and N 2 selectivity in the selective catalytic reduction of NO by CO (CO-SCR) under O 2 -containing conditions is highly challenging because of the competitive reactions of NO x and CO with O 2 . Here, we demonstrate that the interfacial oxygen vacancies (IOVs) generated at the Co 3 O 4 -CeO 2 heterointerfaces by ball-milling-induced strain can remarkably boost both NO x conversion and N 2 selectivity in the temperature range of 100–400 °C. The Co 3 O 4 -CeO 2 -IOV catalyst achieved approximately 100% NO x conversion and 100% N 2 selectivity (200–350 °C, 1–5 vol% O 2 , and 20,000 h −1 ); even under 10 vol% O 2 , it still showed good catalytic performance. The spectroscopy analysis and theoretical calculations reveal that compared with O 2 activation, IOVs are more favorable for the rate-limiting step of NO adsorption and dissociation. This work provides an effective strategy to create IOVs within metal oxide composite catalysts using ball-milling-induced interfacial strain for improving CO-SCR performance.
研究领域:
材料科学
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环境催化
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化学工程
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高影响因子
CANADIAN JOURNAL OF CHEMICAL ENGINEERING
·
2026
·
IF 2.2
Yang Zhang,Yaqi Wu,Rui Sun,Chenyang Yang,Yaohan Fu,Hua Li,Liang Chen
The efficient separation of CH 4 /N 2 represents a significant bottleneck in unconventional natural gas upgrading. Herein, we present an electrochemical charging strategy to prepare anion-modified activated carbon fibre adsorbents (ACF-NO 3 and ACF-SO 4 ). Multiple characterizations confirm the successful enrichment of nitrate (NO 3 − ) and sulphate (SO 4 2− ) ions within the activated carbon fibre pores. Remarkably, the charged adsorbent ACF-SO 4 exhibits outstanding performance with a high CH 4 adsorption capacity of 1.22 mmol · g −1 and an IAST CH 4 /N 2 selectivity of 6.08 at 298 K and 1 bar, significantly exceeding the ACF-blank. Compared to the ACF-blank, the higher isosteric heats of CH 4 adsorption on charged adsorbents indicate the stronger adsorption affinity between the adsorbents and CH 4 after charging. The different affinities with CH 4 and N 2 on the blank and charged ACF imply that the incorporated anions can act as additional adsorption sites and contribute significantly to the efficient CH 4 /N 2 separation. Breakthrough experiments demonstrate the excellent dynamic CH 4 /N 2 separation performance of the charged adsorbents. The static and dynamic cycling tests also confirm the exceptional stability of the charged adsorbents with their performance remaining unchanged. This electrochemical modification strategy provides valuable insights into designing adsorbents for gas adsorption and separation.
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高影响因子
Journal of Materials Chemistry C
·
2022
·Vol. 10
·期 21
·8356-8363
·
IF 8.067
Ye Li,Miaoling Cai,Mengling Shen,Yuting Cai,Rong-Jun Xie
The stability of perovskite nanocrystals (NCs) is greatly limited due to highly dynamic binding of ligands, which hinders their applications in optoelectronic devices. In this paper, a new ligand strategy was employed to prepare CsPbBr3 NCs via a facile room temperature (RT) ligand-assisted reprecipitation (LARP) method, where N1.N2-didodecyl-N1.N1.N2.N2-tetramethylethane-1.2-diaminium bromide (DTDB) as the sole capping ligand and an additional Br resource was used. Compared to other ligands with one coordinating group, this class of bidentate ligand can be tightly anchored to the surface of NCs with double N+ sites. The as-synthesized DTDB-CsPbBr3 NCs exhibited a high photoluminescence quantum yield (PLQY) of 92.3% and also showed a superior colloidal stability even under intense purification for up to ten cycles. Compared to the dodecyltrimethyl ammonium bromide (DTAB) ligand capped-CsPbBr3 NCs, the DTDB-CsPbBr3 NCs display obviously enhanced stability to light, heat and water. X-ray photoelectron spectroscopy (XPS) results revealed that the DTDB-CsPbBr3 NCs have a Br− rich surface, which accounts for the high stability and PLQY. Hence, DTDB is a promising ligand to prepare perovskite NCs with higher optical performance.
研究领域:
材料科学
·
纳米技术
·
光电技术
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DOI
高影响因子
CHINESE JOURNAL OF CHEMICAL PHYSICS
·
2021
·Vol. 34
·期 4
·413-418
·
IF 1.114
Niu Xiao-you,Jiang Shen-long,Zhang Qun
Photocatalytic N 2 fixation has attracted substantial attention in
recent years, as it represents a green and sustainable development route toward
efficiently converting N 2 to NH 3 for industrial
applications. How to rationally design catalysts in this regard remains a
challenge. Here we propose a strategy that uses plasmonic hot electrons in the
highly doped TiO 2 to activate the inert N 2 molecules. The
synthesized semiconductor catalyst Mo-doped TiO 2 shows a
NH 3 production efficiency as high as 134
µmol · g −1 · h −1 under
ambient conditions, which is comparable to that achieved by the conventional
plasmonic gold metal. By means of ultra-fast spectroscopy we reveal that the
plasmonic hot electrons in the system are responsible for the activation of
N 2 molecules, enabling improvement the catalytic activity of
TiO 2 . This work opens a new avenue toward semiconductor
plasmon-based photocatalytic N 2 fixation.
研究领域:
材料科学
·
环境科学
·
化学
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DOI
高影响因子
ACS Catalysis
·
2019
·
IF 12.221
Yan Liu,Xiangdong Kong,Xu Guo,Qiuyao Li,Jingwen Ke,Ruyang Wang,Qunxiang Li,Zhigang Geng,Jie Zeng
Electroreduction of N2 into NH3 represents a promising method for N2 fixation. However, due to the inertness of N≡N covalent triple bonds, this process remains a huge challenge to achieve a high yield rate of NH3. In this work, we designed an effective approach to promoting N2 activation by introducing oxygen vacancies into LaCoO3. In N2 electroreduction, LaCoO3 with oxygen vacancies (denoted as Vo-LaCoO3) exhibited a Faradaic efficiency of 7.6% for NH3 at −0.6 V versus the reversible hydrogen electrode (RHE). Notably, at −0.7 V versus RHE, the yield rate for NH3 of Vo-LaCoO3 reached 182.2 μgNH3 mg–1cat. h–1, which was 2.8 times higher than that (65.3 μgNH3 mg–1 h–1) of pristine LaCoO3. To the best of our knowledge, the yield rate for NH3 of Vo-LaCoO3 approaches the activities of the state-of-the-art catalysts toward N2 electroreduction. Density functional theory calculations revealed that enhanced activation of N2 over Vo-LaCoO3 originated from the increased charge density around the valence band edge via the introduction of oxygen vacancies. Furthermore, the analysis of the thermodynamic limiting potentials for N2 reduction and H2 evolution demonstrated the higher selectivity for N2 electroreduction over Vo-LaCoO3 relative to pristine LaCoO3.
研究领域:
材料科学
·
催化化学
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DOI
高影响因子
Energy Storage Materials
·
2019
·
IF 0
Bingcheng Ge,Yangyang Wang,Yong Sun,Yunping Li,Jianyu Huang,Qiuming Peng
Developing a rechargeable metal-nitrogen battery is desirable for energy conversion and nitrogen fixation as well as an alternative route for a potential and mild ammonia synthesis . Herein, we realized a proof-of-concept for sodium-nitrogen (Na-N 2 ) rechargeable batteries by introducing the alpha-MnO 2 (α-MnO 2 ) nanowire as a catalyst. In addition, we have also demonstrated a reversible reaction of 6Na + N 2. ↔ 2Na 3 N. This system reveals an outstanding reversible capacity of 600 mAh g −1 at 50 mAg −1 , runs ∼80 cycles with a controlled capacity of 400 mAh g −1 at discharge terminal voltage below 1.6 V and achieves a high actual specific energy density based on total active materials (about 4900 Wh/Kg MnO2 ) at the current density of 100 mAg −1 . In addition, a good efficiency of nitrogen fixation (∼26%) has been achieved. These attractive performances are mainly associated with the distinctive channel structure, high conductivity, and outstanding catalytic activity in terms of in-situ environmental transmission electron microscopy investigations. The success of Na-N 2 batteries not only provides an alternative strategy for the next-generation of electrochemical energy-storage devices, but also builds a new trajectory toward green recycling and utilization of N 2 .
研究领域:
能源化学
·
材料科学
·
环境科学
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产品关联
DOI
ACS Applied Energy Materials
·
2022
·
IF 6.959
Peng Huang,Nan Li,Liang Zeng,Yujie Zhu
The long-term goal of electrochemical ammonia (NH3) synthesis under ambient conditions is to replace the Haber–Bosch process. One of the biggest challenges in this field is that the N≡N triple bond is too stable to be activated. Therefore, most research is mainly focused on the development of advanced electrocatalysts to address this challenge. However, the extremely low solubility and slow diffusion of N2 molecules in aqueous electrolytes are usually overlooked. Here, the Bi-loaded Cu hollow microtube with a porous structure is reported as the gas diffusion electrode for N2 electroreduction. Compared with the conventional planar electrode configurations, the hollow gas diffusion electrode (HGDE) possesses unique advantages in breaking through the mass transfer limit of low-solubility gases. It can also provide abundant electrochemically active sites due to its porous structure, forming a gas–liquid–solid three-phase interface that is conducive to electrocatalytic reactions. Besides, the adjustable N2/H3O+ at the three-phase interface can further help enhance the reaction activity and selectivity. As a result, the Bi-loaded Cu HGDE exhibits an NH3 yield of 4.6 μg h–1 cm–2 and a Faradaic efficiency of 5.8% at −0.4 V (vs RHE, reversible hydrogen electrode). This study may stimulate interest in optimizing the electrode structure and developing types of electrodes for efficient electrochemical ammonia synthesis.
研究领域:
材料科学
·
电化学
·
催化科学
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产品关联
DOI
高影响因子
PROCESS SAFETY AND ENVIRONMENTAL PROTECTION
·
2024
·
IF 6.9
You-yun Gong,Zi-ang Jia,Yiwen Fan,Jin-ping Cheng
Rational chemical modification engineering of metal-organic frameworks (MOFs) is an effective means to improve their CO 2 capture efficiency. In this study, we prepare UiO-66 MOF impregnated with different types of aliphatic amines using solvothermal and impregnation techniques, respectively, and investigated their performances in CO 2 adsorption and CO 2 /N 2 separation using the isothermal adsorption method. Aliphatic amines successfully chemically modifies UiO-66, and their molecules effectively occupied the pores of the UiO-66 framework, which has been confirmed by material characterization, experiments, and DFT-FMO calculations. There are significant improvements in the ability to capture CO 2 when aliphatic amines were added to UiO-66 compared to pure UiO-66 (1.39 mmol/g up to 2.11 mmol/g-2.53 mmol/g), attributed to the different types and numbers of amines, and there were also differences in the Zr metal clusters and BDC ligands. Meanwhile, The material has better CO 2 /N 2 adsorption IAST selectivity(98) because its surface area is changed and N 2 does not interact specifically with the adsorbent. Furthermore, the CO 2 adsorption capacity remains constant across multiple adsorption cycles, highlighting the adsorbent's stability and reliability during repetitive CO 2 capture. This study provides new ideas and perspectives for improving the CO 2 capture efficiency of UiO-66.
研究领域:
材料科学
·
环境科学
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DOI
高影响因子
危险品化学品经营许可证（带存储）