JOURNAL OF ALLOYS AND COMPOUNDS
·
2023
·
IF 6.2
Yunpeng Liu,Xupo Liu,Cuicui Zhang,Ye Chen,Zhitao Wang,Gangya Wei,Jing Zhang,Tianfang Yang,Fengxian Zhang,Shuyan Gao
Fe-N-C catalysts have served as ideal catalysts for oxygen reduction reaction (ORR), but the strong adsorption to ORR-relevant intermediates and less utilization of Fe-N x sites endow those catalysts with inferior performance. Here, an efficient catalyst consisted of Fe-N x species and FeF 2 /Fe 3 C nanoparticles co-anchored on N, F co-doped carbon nanotubes (Fe-NF-CNTs) has been constructed through a surface modification strategy. Sodium trifluoroacetate as functional linker modified on metal-organic framework surface promotes to form abundant and accessible active sites. FeF 2 /Fe 3 C nanoparticles and hydrogen fluoride generated in pyrolysis process facilitate to construct N, F co-doped CNTs with defects and holes. N, F co-doping modifies the adsorption characteristic of Fe-N x sites, while CNTs improve the accessibility of active sites and the capability of material transport. Therefore, Fe-NF-CNTs exhibits outstanding activity (E 1/2 = 0.85 V) and stabilization (ΔE = 6 mV, 10k cycles). Impressively, Fe-NF-CNTs delivers high power density (144 and 68 mW cm –2 ) and cycle stability (300 and 60 h) in liquid and flexible Zn-air batteries, respectively. This work provides a surface modification strategy to guide the tuning of electronic structure of efficient ORR catalysts designed for renewable green energy.
研究领域:
材料科学
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电化学
·
催化科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2021
·
IF 10.588
Cheng Zeng,Yan Wang,Tong Xiao,Zhicheng Yan,Jinquan Wan,Quanmo Xie
To improve the efficacy of organic pollutant removal using sulfate radicals, we designed MIP@C-Fe-Nx, a molecularly imprinted material capable of targeting the degradation of tetrabromobisphenol A (TBBPA), which can be used as both adsorbent and catalyst to recognize and degrade Tetrabromobisphenol A (TBBPA) accurately, and the final removal rate of TBBPA can reach 104.6 mg·g −1 . Based on the synergistic effects of MIP@C-Fe-Nx on the excellent organic pollutant recognition and catalytic performance, low concentrations of TBBPA can be pre-targeted, concentrated, and fixed on the surface of MIP, and degraded simultaneously in-situ by·OH and SO 4 •- which are produced by activating PS with C-Fe-Nx. Recognition experiments demonstrated that MIPs had perfect performance in recognizing and adsorbing TBBPA and debromination intermediates. The DFT calculations and HPLC-MS analysis indicated that MIP@C-Fe-Nx had a targeted recognition and accumulation for TBBPA and debromination intermediates, for example, dibromobisphenol A, monobromobisphenol A, and bisphenol A, thus avoid the formation of toxic intermediates causing secondary contamination.
研究领域:
环境科学
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材料科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Ting Yang,Shisuo Fan,Yang Li,Qi Zhou
A high-efficient iron-based heterogeneous catalyst is desired to active peroxymonosulfate (PMS). Due to a large catalytic contribution of atomically dispersed Fe-N x sites, single-atom iron–nitrogen-carbon catalysts exhibit superior performance in the catalytic activation of PMS. Herein, a sequence of Fe-N-C SACs with atomically dispersed Fe-N x sites, Fe SA -N-C and Fe SA -N/C, were prepared from Fe-doped ZIF-8 and FePc@ZIF-8, respectively. Single-atom Fe-N x sites were confirmed to be the main active sites for PMS activation. Fe SA -N/C-20 with a higher density of Fe-N x sites exhibited superior catalytic performance to N/C, Fe SA -N-C, Fe SA -N/C-15, and Fe SA -N/C-25 for BPA degradation. Integrated with chemical quenching experiments, electron spin resonance (ESR), in-situ Raman spectra, and electrochemical analysis, a nonradical pathway was demonstrated to dominate the degradation of BPA in the PMS + Fe SA -N/C-20 system. More importantly, the nature of this nonradical pathway was found to be an electron-transfer regime instead of a high-valent iron or singlet oxygenation process. The BPA was adsorbed onto the Fe-N x site by a “donor–acceptor complex” mechanism to form a nonradical PMS* intermediate during the process. Benefiting from this mechanism, the PMS + Fe SA -N/C-20 system showed wide pH adaptation and high resistance to inorganic anions.
研究领域:
环境科学
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
Green Energy & Environment
·
2020
·
IF 6.395
Hongtai Li,Yanxiao Chen,Quan Jin,Wei Xiang,Benhe Zhong,Xiaodong Guo,Bao Wang
Serious shuttle effect and sluggish conversion kinetics of lithium polysulfides (LiPSs) have a massive impact on obstructing the practical application of lithium-sulfur (Li–S) batteries. To address such issues, Fe-Nx sites enriched microporous nanoflowers planted with tangled bamboo-like carbon nanotubes (Fe-Nx-C/Fe 3 C-CNTs NFs) are found to be effective catalytic mediators with strong anchoring capabilities for LiPSs. The bamboo-like carbon nanotubes catalyzed by Fe 3 C/Fe entangled each other to form a conductive network, which encloses a flower-like microporous carbon core with embedded well-dispersed Fe-Nx active sites. As expected, electrons smoothly transfer along the dense conductive bamboo-like carbon network while the flower-like carbon core consisting of micropores induces the homogeneous distribution of tiny sulfur and favors the lithium ions migration with all directions. Meanwhile, Fe-Nx sites strongly trap long-chain LiPSs with chemical anchoring, and catalyze the redox conversion of LiPSs. Due to the aforementioned synergistic effects, the [email protected] /Fe 3 C-CNTs NFs cathode exhibited a remarkable specific capacity (635 mAh g s −1 ) at 3 C and a favorable capacity decay with 0.04% per cycle even after 400 cycles at 1 C.
研究领域:
材料科学
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能源存储
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电化学
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
·
2022
·
IF 4.598
Wei-Chang Chen,Xiao-Shuang Guo,Ze-Yu Liu,Chuan-Qing Huang,Jian-Shan Ye,Hai-Yang Liu,Xin-Yan Xiao
Fe-based nanoparticles encapsulated in carbon can effectively promote the ORR activity of the neighboring Fe–N x and prevent the dissolution of metal nanoparticles to ensure the long-term durability of catalysts. Herein, we employed a facile two step pyrolysis strategy to construct “plane-active sites” structure, namely FeO y nanoparticles embedded in carbon were loaded on two dimensional (2D) porous carbon with exposed abundant Fe–N x active sites (FeOy@C/Fe-N x /C). The optimized FeO y @C/Fe-N x /C catalyst with low Tafel slope (48 mV dec −1 ) and nearly-four-electron selectivity (3.91–3.97) showed excellent performance towards ORR with a more positive shift of 15 mV of half-wave potential (E 1/2 = 0.856 V) than that of commercial Pt/C (E 1/2 = 0.841 V) in alkaline solution, and also had a superior long-term stability and methanol resistance as compared with commercial Pt/C. The excellent electrochemical performance of FeO y @C/Fe-N x /C can be attributed to FeO y @C structure, exposed abundant Fe–N x active sites and two dimensional porous carbon with a large specific surface area.
研究领域:
材料科学
·
电化学
·
纳米技术
✓ 已验证
DOI
高影响因子
Journal of Energy Chemistry
·
2023
·
IF 13.1
Katam Srinivas,Zhuo Chen,Anran Chen,Fei Ma,Ming-qiang Zhu,Yuanfu Chen
The development of efficient single-atom catalysts (SACs) for the oxygen reduction reaction (ORR) remains a formidable challenge, primarily due to the symmetric charge distribution of metal single-atom sites (M-N 4 ). To address such issue, herein, Fe-N x sites coupled synergistic catalysts fabrication strategy is presented to break the uniform electronic distribution, thus enhancing the intrinsic catalytic activity. Precisely, atomically dispersed Fe-N x sites supported on N/S-doped mesoporous carbon (NSC) coupled with FeS@C core-shell nanoparticles (FAS-NSC@950) is synthesized by a facile hydrothermal reaction and subsequent pyrolysis. Due to the presence of an in situ-grown conductive graphitic layer (shell), the FeS nanoparticles (core) effectively adjust the electronic structure of single-atom Fe sites and facilitate the ORR kinetics via short/long-range coupling interactions. Consequently, FAS-NSC@950 displays a more positive half-wave potential ( E 1/2 ) of 0.871 V with a significantly boosted ORR kinetics (Tafel slope = 52.2 mV dec −1 ), outpacing the commercial Pt/C ( E 1/2 = 0.84 V and Tafel slope = 54.6 mV dec −1 ). As a bifunctional electrocatalyst, it displays a smaller bifunctional activity parameter (Δ E ) of 0.673 V, surpassing the Pt/C-RuO 2 combination (Δ E = 0.724 V). Besides, the FAS-NSC@950-based zinc-air battery (ZAB) displays superior power density, specific capacity, and long-term cycling performance to the Pt/C-Ir/C-based ZAB. This work significantly contributes to the field by offering a promising strategy to enhance the catalytic activity of SACs for ORR, with potential implications for energy conversion and storage technologies.
研究领域:
电化学
·
材料科学
·
能量转换与存储
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2021
·
IF 9.028
Li Gong,Xiaojiang Qiu,Paul G. Tratnyek,Chengshuai Liu,Feng He
FeNX in Fe single-atom catalysts can be the active site for adsorption and activation of reactants. In addition, FeNX species have been shown to facilitate electron transfer between Fe and the carbon supports used in newly developed metal–air batteries. We hypothesized that the combination of FeNX species with granular zero-valent iron (ZVI) might result in catalyzed reductive decontamination of groundwater contaminants such as trichloroethylene (TCE). Here, such materials synthesized by ball milling microscale ZVI with melamine and the resulting N species were mainly in the form of pyridinic, pyrrolic, and graphitic N. This new material (abbreviated as N–C-mZVIbm) dechlorinated TCE at higher rates than bare mZVIbm (about 3.5-fold) due to facilitated electron transfer through (or around) the surface layer of iron oxides by the newly formed Fe–NX(C). N–C-mZVIbm gave higher kTCE (0.4–1.14 day–1) than mZVIbm (0–0.4 day–1) over a wide range of pH values (4–11). Unlike most ZVI systems, kTCE for N–C-mZVIbm increased with increasing pH values. This is because the oxide layer that passivates Fe0 at a high pH is disrupted by Fe–NX(C) formed on N–C-mZVIbm, thereby allowing TCE dechlorination and HER under basic conditions. Serial respike experiments gave no evidence of decreased performance of N–C-mZVIbm, showing that the advantages of this material might remain under field applications.
研究领域:
环境科学
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材料化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF POWER SOURCES
·
2026
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IF 8.4
Xu Meng,Qingliang Guo,Zigeng Liu,Wei Wang
Developing low-cost, high-performance non-precious-metal catalysts for the oxygen reduction reaction (ORR) is crucial for clean-energy technologies. Herein, we propose a “monomer-coordination/in-situ polymerization” strategy in which inexpensive acrylonitrile monomers are pre-coordinated with Fe 3+ before radical polymerization, yielding uniformly Fe-doped polyacrylonitrile (PAN) (denoted Fe + PAN). Subsequent electrospinning and pyrolysis of this precursor afford Fe-N x nanofiber catalysts (denoted O-Fe-N-C). Compared with the conventional “polymerize-then-dope-Fe” route (denoted T-Fe-N-C), this approach markedly reduces the steric hindrance of PAN chains, strengthens Fe-N interactions, increases the density of Fe-N x active sites after pyrolysis, and suppresses Fe agglomeration. In 0.1 M KOH, O-Fe-N-C delivers an ORR half-wave potential of 0.878 V (vs RHE), outperforming commercial Pt/C. When employed as the air cathode in a Zn-air battery, the O-Fe-N-C cell exhibits an open-circuit voltage of 1.46 V and a peak power density of 133.91 mW cm −2 at 205.7 mA cm −2 , surpassing the Pt/C benchmark. This work provides a molecular-level design paradigm for scalable synthesis of low-cost, high-performance Fe-N x ORR catalysts.
✓ 已验证
DOI
高影响因子
Science China-Chemistry
·
2020
·Vol. 63
·期 6
·810-817
·
IF 6.356
He Qian,Meng Yuying,Zhang Hao,Zhang Ying,Sun Qingdi,Gan Tao,Xiao Huajian,He Xiaohui,Ji Hongbing
Recently, nitrogen-doped porous carbon supported single atom catalysts (SACs) have become one of the most promising alternatives to precious metal catalysts in oxygen reduction reaction (ORR) due to their outstanding performance, especially those derived from porphyrin-based materials. However, most of them involve other metal residuals, which would cause the tedious pre- and/or post-treatment, even mislead the mechanistic investigations and active-site identification. Herein, we report a precursor-dilution strategy to synthesize Fe SACs through the Schiff-based reaction via co-polycondensation of amino-metalloporphyrin, followed by pyrolysis at high temperature. Systematic characterization results provide the compelling evidence of the dominant presence of atomically dispersed Fe-N x species. Our catalyst shows superior ORR performance with positive half-wave potential ( E 1/2 =0.85 V vs. RHE) in alkaline condition and moderate activity ( E 1/2 =0.68 V vs. RHE) under the acidic condition, excellent methanol tolerance and good long-term stability. All the results indicate Fe SACs would be a promising candidate for replacing the precious Pt in metal-air batteries and fuel cells.
研究领域:
材料科学
·
电化学
·
催化科学
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry A
·
2024
·
IF 10.7
Katam Srinivas,Zhuo Chen,Anran Chen,He Huang,Chengtao Yang,Fei Wang,Ming-qiang Zhu,Yuanfu Chen
Replacing platinum-based electrocatalysts with iron single-atom catalysts (Fe–N4–C) for the oxygen reduction reaction (ORR) remains challenging due to the symmetric electronic structure of atomically dispersed Fe–N4 sites and sluggish kinetics. To address this issue, we introduce Cu–Nx sites and graphene-encapsulated core–shell Fe–Cu nanoalloy (FeCu@G) particles into the Fe–Nx site surroundings through the self-assembly and pyrolysis of a metal–organic framework (MOF). This strategy leverages synergistic interactions with the associated species to modify the uniform electronic structure of Fe single-atom sites, thereby enhancing oxygen-adsorption/desorption kinetics. Density functional theory (DFT) calculations reveal that the incorporation of Cu–Nx sites and FeCu@G nanoalloy particles significantly alters the electronic structure of Fe–Nx sites, leading to improved ORR activity. Consequently, the optimized FeCu-DSAs@CNT, comprising dual single-atom sites (DSAs: Fe–Nx and Cu–Nx) and FeCu@G nanoalloy within MOF-derived nitrogen-doped carbon nanotubes (CNTs), exhibits a significantly improved half-wave potential (E1/2 = 0.91 V) and feasible ORR kinetics (Tafel slope = 48.15 mV dec−1), surpassing the Pt/C benchmark (E1/2 = 0.847 V and Tafel slope = 56.76 mV dec−1). Notably, FeCu-DSAs@CNT shows a 58 mV more positive E1/2 compared to monometallic Fe–SAs@CNT, attributed to synergistic interactions with Cu species. Moreover, it demonstrates excellent power density, specific capacity, and cycling stability in a lab-made zinc–air battery, outpacing the Pt/C-battery. This study addresses gaps in understanding Fe–Nx site interactions with associated species, providing valuable insights for the advancement of Fe–Nx–C electrocatalysts.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Zhenyu Yan,Wenyu Gao,Chenkai Zhong,Qiangqiang Jiao,Xiuyun Zhao,Jia Liu
Fe-Nx sites can activate peroxymonosulfate (PMS) in advanced oxidation processes (AOPs) to produce various reactive oxygen species, and have great potential for removing tetracycline (TC), but their formation and catalytic mechanism are rarely studied. Herein, the Fe/N-C catalyst was prepared by crosslinking chitosan (CS) using a coordination complex of Fe 2+ and phenanthroline as the precursor for FeNx. The results of crystal structure, lattice constant, chemical state of N element and structural analysis have demonstrated the successful construction of FeNx sites. The degradation experiments confirmed that the removal efficiency of tetracycline reached up to 90.7 % within 15 min, with a degradation rate of up to 0.184 min −1 . Moreover, the material has exhibited excellent performance in complex water environments and within a broad pH range (pH = 2.30 ∼ 9.88). Mechanism analysis proves that the active substances in the system are 1 O 2 , •O 2 − , SO 4 •− , •OH and Fe IV = O, of which 1 O 2 played the principal role. The FeNx structure is the primary active site, where the redox cycle between Fe 2+ and Fe 3+ , electron transport between pyridinic N, electron-deficient C and PMS produces active components. In addition, based on the various intermediate products detected, two possible TC degradation pathways are reasonably speculated. In this study, the highly active FeNx sites were successfully constructed, and elucidated their activation mechanism towards PMS, which proved the broad prospect of Fe/N-C materials in pollutant degradation.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
CARBON
·
2025
·
IF 11.6
Hao Liu,Guangwu Yang,Fuqiang Duan,Xiaoli Qiu,Guangrun Ren,Tingting Zhang,Jinshi Yu,Yanli Chen
In this study, we present a novel synthesis of hierarchical carbon nanocages (HCNC) with diverse pore structures tailored for efficient oxygen reduction reactions (ORR) and advanced performance in zinc-air batteries (ZABs). The hierarchical structure was achieved using a dissolution-recrystallization strategy, where N, N-dimethylpyrrolidone was employed to activate the zeolite β framework. The resultant hierarchical β-zeolite nanocage (HβNC) was subsequently used as a template for synthesizing the HCNC via chemical vapor deposition. The HCNC exhibited a multilevel porous structure, including micropores, mesopores, and macropores, optimizing mass transfer and providing high surface area for active site exposure. By introducing Fe-Nx active sites through an impregnation-pyrolysis method, the Fe–N/HCNC catalyst was synthesized and tested for ORR. The catalyst demonstrated superior activity, stability, and corrosion resistance, outperforming commercial Pt/C catalysts with a half-wave potential of 0.905 V. Additionally, the Fe–N/HCNC-based ZAB displayed excellent electrochemical performance, high power density, and enhanced durability. The This work not only provides a novel approach to carbon nanocage synthesis, and the unique structural characteristics of HCNC offer promising opportunities in energy storage and conversion technologies, addressing limitations in catalyst stability and mass transport.
研究领域:
材料科学
·
电化学
·
能源存储与转换
✓ 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）