ENVIRONMENTAL SCIENCE & TECHNOLOGY
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2022
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IF 11.357
Fanxu Meng,Jiang Xu,Huiwang Dai,Yunlong Yu,Daohui Lin
Surface modification of microscale Fe powder with nitrogen has emerged recently to improve the reactivity of Fe0 for dechlorination. However, it is unclear how an even incorporation of a crystalline iron nitride phase into Fe0 nanoparticles affects their physicochemical properties and performance, or if Fe0 nanoparticles with a varied nitridation degree will act differently. Here, we synthesized nitridated Fe0 nanoparticles with an even distribution of N via a sol–gel and pyrolysis method. Nitridation expanded the Fe0 lattice and provided the Fe4N species, making the materials more hydrophobic and accelerating the electron transfer, compared to un-nitridated Fe0. These properties well explain their reactivity and selectivity toward trichloroethylene (TCE). The TCE degradation rate by nitridated Fe0 (up to 4.8 × 10–2 L m–2 h–1) was much higher (up to 27-fold) than that by un-nitridated Fe0, depending on the nitridation degree. The materials maintained a high electron efficiency (87–95%) due to the greatly suppressed water reactivity (109–127 times lower than un-nitridated Fe0). Acetylene was accumulated as the major product of TCE dechlorination via β-elimination. These findings suggest that the nitridation of Fe0 nanoparticles can change the materials’ physicochemical properties, providing high reactivity and selectivity toward chlorinated contaminants for in situ groundwater remediation.
研究领域:
环境科学
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纳米材料科学
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产品关联
DOI
PubMed
高影响因子
ACS Sustainable Chemistry & Engineering
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2025
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IF 7.3
Rui Liu,Huanzhong Zeng,Lei Zhao,Yuanyou Peng,Meimei Yuan,Yumeng Wang,Gaoyang Li,Shengqiang Nie,Fen Ran
Hard carbon anodes exhibit superior storage capacity and rate performance due to their special structure, when applied in various alkali metal ion batteries. The ability to store Li+ and Na+ is related to the proportion of pseudographite domains and the distribution of the pore structure. This work uses a one-step carbonization strategy to generate uniformly sized Fe2N nanoparticles to be embedded into hard carbon, the former could catalyze the microcrystalline structure of the latter. The as-prepared hard carbon exhibits up to 54% occupation of microcrystalline domains, while its specific surface area (867.1 m2 g–1) and the maximum probable aperture (6.220 Å) are larger than that of pure hard carbon (519.2 m2 g–1 and 4.680 Å). The composites show a capacity of 581.8 mAh g–1 in LIBs and 334.1 mAh g–1 in SIBs at 0.05 A g–1. It can stably cycle for 2000 times with capacity retention of 97.92% in LIBs and cycles for 1500 cycles (98.64%) in SIBs at 2.0 A g–1. This work provides a simple preparation strategy and enriches the regulation mechanism of microcrystal structure for hard carbon anodes, which would be references for the regulation of “fast-charging” carbon-based anode materials.
研究领域:
材料科学
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纳米技术
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电化学
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储能
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电池技术
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2024
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IF 13.3
Tong Hu,Wenjun Zhou,Haijiao Xie
Lattice engineering of Fe 0 based on heteroatom doping holds great promise in water purification owing to their tunable geometric and electronic structure. However, there is limited understanding of how nitrogen atom in Fe 0 lattice structure affects its local microenvironment and corresponding reactivity toward target contaminants. Herein, microscale zero-valent iron with interstitial N doping (N-mZVI) was successfully prepared by a facile mechanochemical method for heavy metal pollution control. N-mZVI exhibited excellent reactivity for Cr(VI) elimination, and both removal efficiency and conversion rate could reach 100 %, which was 8.06 and 2.73 times higher than that of pristine ball milled mZVI, respectively. Besides, the rate constant of various heavy metals sequestration (Cr(VI), Ni(II), Pb(II), Cu(II), and Cd(II)) over N-mZVI was 61.3 ∼ 115.6-fold faster than that of pristine ball milled mZVI. N-mZVI was also demonstrated to be pH-universal, long-term stability, and environmental applicability. Experimental results and theoretical calculations indicated that tensile strain induced by interstitial N doping expanded Fe 0 lattice and weakened the lattice Fe-Fe interaction, thus significantly accelerating electron transport dynamics in Fe 0 core. Meanwhile, iron nitride species on the surface of N-mZVI promoted electron transfer from iron shell layer to heavy metals. This work comprehensively investigates the structure–property relationships of lattice engineering-based N-mZVI, and provides a new insight into rational design of modified mZVI with high reactivity.
研究领域:
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
APPLIED SURFACE SCIENCE
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2023
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IF 6.7
Wei Wang,Jialin Gong,Qing Long,Haitao Wang,Junlin Huang,Wei Dang,Liang Chen,Gangyong Li,Zhaohui Hou,Wenyuan Xu
Taking into consideration the sluggish kinetics of the oxygen reduction reaction (ORR) and the distinct three-phase environment of the electrode, it is crucial to optimize the surface structure of the electrocatalyst. This study employs a sol–gel approach to synthesize a Fe-Fe 3 N composite three-dimensional nitrogen-doped carbon framework (Fe-Fe 3 N/3DNC) and utilize it as the electrocatalyst for a zinc-air battery. The material possesses a multi-dimensional cross-linking frame structure comprised of one-dimensional and two-dimensional crosslinks, which effectively reduce the diffusion mean-free path of oxygen. Moreover, the iron–nitrogen site and nitrogen-rich carbon substrate both exhibit exceptional electrocatalytic activity for ORR. Consequently, a conventional liquid zinc-air battery utilizing this material as the air cathode catalyst exhibits a maximum power density of 242.8 mW cm −2 , surpassing that of commercial Pt/C. Additionally, DFT calculations further confirm the crucial enhancing influence of Fe 3 N in the Fe-Fe 3 N/3DNC composite on ORR. This research provides valuable insights for the development of ORR electrocatalysts with outstanding efficiency.
研究领域:
材料科学
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电化学
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能源存储与转换
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL POLLUTION
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2023
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IF 8.9
Jishao Jiang,Rui Hou,Huilin Cui,Dong Liu,Guangxuan Yan,Yujuan Fan,Ke Cheng,Zhiguo Cao
New pollutants, pharmaceuticals and personal care products (PPCPs), accumulate in sewage sludge (SS) in wastewater treatment plants (WWTPs), posing risks to the environment and to human health. In the present study, the fates of typical PPCPs, carbamazepine (CBZ), triclosan (TCS), ibuprofen (IBU) and galaxolide (HHCB), were examined during WW treatment. Additionally, SS collected from a WWTP was used for aerobic composting to investigate the influences of micron-sized Fe 3 O 4 (M-Fe) and nano-sized Fe 3 O 4 (N–Fe) on the degradation of these PPCPs and the succession of microbial communities during the composting process. The results showed that the mean concentrations of CBZ, TCS, IBU and HHCB in the influent of the WWTP were 926.5, 174.4, 8869, and 967.3 ng/g, respectively, and in the effluent were 107.6, 47.0, 283.4, and 88.4 ng/g, respectively. The removal rate averaged ∼80%, while the enrichment rates of the PPCPs in SS ranged from 37.2% to 60.5%. M-Fe and N–Fe reduced NH 3 emissions by 32.9% and 54.1% and N 2 O emissions by 26.2% and 50.8%, respectively. Moreover, the addition of M-Fe and N–Fe effectively increased PPCP degradation rates 1.12–1.66-fold. During the whole process, the additions of M-Fe and N–Fe significantly shifted microbial community structure, and the abundances of Proteobacteria, Chloroflexi, and Actinobacteria were increased during the thermophilic stage, marking them as key PPCP-degrading phyla. Taken together, our results indicated that the addition of M-Fe and N–Fe is an effective method for improving the quality of end compost and accelerating the degradation of PPCPs.
研究领域:
环境科学
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微生物学
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废物管理
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）