Sustainable Energy & Fuels
·
2019
·Vol. 3
·期 12
·3455-3461
·
IF 4.912
Bomin Feng,Xiuju Wu,Yanli Niu,Wei Li,Yunxi Yao,Weihua Hu,Chang Ming Li
Fe/N–C catalysts show great potential for the oxygen reduction reaction (ORR) but their catalytic activity should be further improved for practical application. Here, we report a high performance Fe/N–C hollow sphere with excellent ORR activity in both alkaline and acidic solutions. It is synthesized via pyrolysis of a melamine/Fe-incorporated polydopamine nanosphere precursor at 800 °C in an argon atmosphere. The N-rich melamine in the precursor affords abundant N dopants to form dense Fe–Nx active sites and also facilitates the formation of micropores in the catalyst via the gasification effect, together improving the ORR activity. The as-reported Fe/N–C catalyst outperforms the Pt/C catalyst in basic media (45 mV more positive half wave potential), approaches the Pt/C catalyst in acidic media (55 mV lower half wave potential), and exhibits impressive performance in Zn–air primary batteries.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2024
·
IF 4.9
Qian Liu,Chenye Zhang,Meimei Ren,Jinyi Wang,Leixin Feng,Yixuan Wang,Chuang Liu,Ningru Xiao,Haiming Zhang
Development of low Pt-loading electrocatalyst with enhanced activity towards oxygen reduction reaction (ORR) is highly demanded for widespread penetration of clean energy technologies. Heterointerface regulation can effectively optimize the electronic structure and intrinsic activity of the carbon supported Pt-based electrocatalyst to reduce Pt consumption. Here, by judicious choice of a sulfur-doped Fe-N-C (Fe-NS-C) as support, we construct a novel Pt/Fe-N-C heterointerface with sulfur incorporation and develop a hybrid electrocatalyst (denoted as Pt@Fe-NS-C) with ultralow Pt-loading (1.51 wt%). The incorporation of sulfur triggers the charge redistribution at the heterointerface and reduces the electron transfer from Pt to Fe-NS-C, prompting the electron density around Pt sites and boosting the electrocatalytic performance towards ORR (half-wave potential: 0.903 V; mass activity of 1.28 A mg −1 Pt at 0.9 V). In comparison, Pt species dispersed onto Fe-N-C without sulfur doping (Pt@Fe-N-C) are electron-deficient, which is not conductive to activate O 2 and results in inferior ORR activity. Zinc-air battery fabricated with Pt@Fe-NS-C as the cathode catalysts shows a large peak power density and a specific capacity of 806.7 mAh g −1 Zn . This work offers an effective way to tailor the heterointerface of hybrid or supported electrocatalyst with optimized electronic structures towards advanced electrocatalysis .
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Wendong Liu,Lin Chu,Chenghui Zhang,Pengjuan Ni,Yuanyuan Jiang,Bo Wang,Yizhong Lu,Chuanxia Chen
Revealing the relationship between composition and enzyme-like activities is essential for the rational designs of nanozymes and related assays with improved performances. Here, a series of Fe-N co-doped porous carbon (Fe-N-C) nanozymes containing different Fe contents have been successfully prepared by facilely pyrolyzing hemin trapped zeolitic-imidazolate-frameworks (Hemin@ZIF-8). The special doping agent hemin will endow Fe-N-C with exceptionally high peroxidase-mimetic activities due to the hierarchically porous structure, high specific surface area, and high dispersed Fe-N x sites. Notably, the optimal Fe 55 -N-C nanozymes are used to detect bio-enzymes, by taking alkaline phosphatase (ALP) as a model, based on the inhibition of nanozymatic activity by ascorbic acid (AA). A linear activity range of 0.05–20 U/L is obtained with a low detection limit of 0.03 U/L, which is superior to the most published optical ALP assays. This work provides not only a new method for the design of the transition metal-N-C nanozyme with enhanced peroxidase-like activity but also a promising strategy for the detection of ascorbic acid-generating bio-enzymes with the assistance of specific substrates.
研究领域:
生物化学
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纳米医学
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分析化学
✓ 已验证
产品关联
DOI
高影响因子
Small
·
2019
·Vol. 16
·期 6
·1906057
·
IF 10.856
Xueping Sun,Peng Wei,Songqi Gu,Jinxu Zhang,Zheng Jiang,Jing Wan,Zhaoyang Chen,Li Huang,Yue Xu,Chun Fang,Qing Li,Jiantao Han,Yunhui Huang
Highly active and durable bifunctional oxygen electrocatalysts are of pivotal importance for clean and renewable energy conversion devices, but the lack of earth-abundant electrocatalysts to improve the intrinsic sluggish kinetic process of oxygen reduction/evolution reactions (ORR/OER) is still a challenge. Fe-N-C catalysts with abundant natural merits are considered as promising alternatives to noble-based catalysts, yet further improvements are urgently needed because of their poor stability and unclear catalytic mechanism. Here, an atomic-level Fe-N-C electrocatalyst coupled with low crystalline Fe 3 C-Fe nanocomposite in 3D carbon matrix (Fe-SAs/Fe 3 C-Fe@NC) is fabricated by a facile and scalable method. Versus atomically FeN x species and crystallized Fe 3 C-Fe nanoparticles, Fe-SAs/Fe 3 C-Fe@NC catalyst, abundant in vertical branched carbon nanotubes decorated on intertwined carbon nanofibers, exhibits high electrocatalytic activities and excellent stabilities both in ORR ( E 1/2 , 0.927 V) and OER ( E J=10 , 1.57 V). This performance benefits from the strong synergistic effects of multicomponents and the unique structural advantages. In-depth X-ray absorption fine structure analysis and density functional theory calculation further demonstrate that more extra charges derived from modified Fe clusters decisively promote the ORR/OER performance for atomically FeN 4 configurations by enhanced oxygen adsorption energy. These insightful findings inspire new perspectives for the rational design and synthesis of economical–practical bifunctional oxygen electrocatalysts.
研究领域:
材料科学
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电化学
·
能源转换技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Environmental Science-Advances
·
2023
·Vol. 2
·期 5
·731-739
·
IF 0
Wen Wen,Yina Liu,Zhongping Li,Guangming Wen,Hung-Wing Li,Li Li
In this study, we report a simple pyrolytic strategy for N–C co-doped Fe-based nanoparticles (Fe–N–C) and exhibit their oxidase-mimicking and peroxidase-mimicking activity in a chromogenic reaction with 3,3′,5,5′-tetramethylbenzidine dihydrochloride (TMB) as a substrate. Structural analysis revealed that Fe–NX and Fe3C structures were formed with Fe-Imace coordination compounds as precursors and melamine as the nitrogen source, which provided abundant active sites for the Fe–N–C nanozyme. Interestingly, owing to the blocking effect triggered by π–π stacking between the tetracycline antibiotics (TCs) tetraphenyl skeleton and Fe–N–C, the substrate affinity of the Fe–N–C was significantly blocked, resulting in the solution fading. Under the optimum conditions, the UV absorption intensity versus the concentration of TCs was found to be linear over the range of 0.08–90 μM for tetracycline (TC), 0.1–80 μM for chlortetracycline (CTC) and 0.09–100 μM for oxytetracycline (OTC). The detection limits were 62 nM for TC, 85 nM for CTC and 88 nM for OTC. The Fe–N–C displayed good storage and long-term stability when stored at 4 °C for 30 days. In addition, based on its superparamagnetism, Fe–N–C can be effectively recycled and reused through an external magnetic field, avoiding secondary pollution.
研究领域:
分析化学
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生物医学工程
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环境科学
✓ 已验证
DOI
ADVANCED MATERIALS
·
2024
·
IF 27.4
Huiwen Zhang,Hsiao-Chien Chen,Solmaz Feizpoor,Linfeng Li,Xia Zhang,Xuefei Xu,Zechao Zhuang,Zhishan Li,Wenyu Hu,Rony Snyders,Dingsheng Wang,Chundong Wang
The interaction between oxygen species and metal sites of various orbitals exhibits intimate correlation with the oxygen reduction reaction (ORR) kinetics. Herein, a new approach for boosting the inherent ORR activity of atomically dispersed Fe−N−C matrix is represented by implanting Fe atomic clusters nearby. The as-prepared catalyst delivers excellent ORR activity with half-wave potentials of 0.78 and 0.90 V in acidic and alkaline solutions, respectively. The decent ORR activity can also be validated from the high-performance rechargeable Zn–air battery. The experiments and density functional theory calculations reveal that the electron spin-state of monodispersed Fe active sites is transferred from the low spin (LS, t 2g 6 e g 0 ) to the medium spin (MS, t 2g 5 e g 1 ) due to the involvement of Fe atomic clusters, leading to the spin electron filling in σ∗ orbit, by which it favors OH − desorption and in turn boosts the reaction kinetics of the rate-determining step. This work paves a solid way for rational design of high-performance Fe-based single atom catalysts through spin manipulation.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2022
·
IF 9.221
Zhiwen Gan,Tian Zhang,Xuanxuan An,Qin Tan,Shujun Zhen,Xiaoli Hu
Numerous ratiometric fluorescence nanozyme sensors are developed, though, fluorescence-scattering ratiometric sensors based on nanozymes are hardly reported. First-order scattering (FOS) could be quenched due to inner filter effect of quenchers on scattering signals. Meanwhile, Second-order scattering (SOS) depended on FOS. Based on the principle, we designed a novel nanozyme sensor by coupling fluorescence (FL) and SOS. Specifically, Fe-N-C nanozyme (Fe-HCNP) was fabricated by doping Fe into carbon-nitrogen polymers via formamide condensations . Fe-HCNP possessed robust oxidase-like activity, effectively transforming O 2 into ·O 2 - and ·OH. Then, Fe-HCNP and o-phenylenediamine (OPD) severed as a hybrid system to construct an FL-SOS ratiometric sensor for ascorbic acid (AA). Fe-HCNP with large size possessed strong SOS. After being added into the Fe-HCNP/OPD system, AA could fast be oxidized to dehydroascorbic acid (DAA) due to Fe-HCNP as oxidase mimics. Subsequently, fluorescent quinoxaline derivative (DFQ) was produced after condensation reactions between DAA and OPD, causing an increase in fluorescence. Meanwhile, the intensity of FOS was reduced because FOS peaks of Fe-HCNP overlapped absorption bands of DFQ, causing a decrease in SOS. The FL-SOS ratiometric sensor for AA showed outstanding advantages of high specificity and fast. Overall, this work provided a new strategy for nanozyme ratiometric sensors.
研究领域:
生物化学
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纳米医学
·
分析化学
✓ 已验证
产品关联
DOI
高影响因子
Small
·
2024
·
IF 13
Ziyi Xu,Shihao Wang,Wenmao Tu,Ling Shen,Lu Wu,Shilong Xu,Haining Zhang,Hongfei Pan,Xiao-Yu Yang
Stable, efficient, and economical bifunctional electrocatalysts for oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) are needed for rechargeable Zn–air batteries. In this study, a directional electron transfer pathway is exploited in a spatial heterojunction of Co y Ni x @Fe─N─C heterogeneous catalyst for effective bifunctional electrolysis (OER/ORR). Thereinto, the Co/Ni alloy is strongly coupled to the Fe─N─C support through Co/Ni─N bonds. DFT calculations and experimental findings confirm that Co/Ni─N bonds play a bridging role in the directional electron transfer from Co/Ni alloy to the Fe─N─C support, increasing the content of pyridinic nitrogen in the ORR-active support. In addition, the discovered directional electron transfer mechanism enhances both the ORR/OER activity and the durability of the catalyst. The Co 0.66 Ni 0.34 @Fe─N─C with the optimal Ni/Co ratio exhibits satisfying bifunctional electrocatalytic performance, requiring an ORR half-wave potential of 0.90 V and an OER overpotential of 317 mV at 10 mA cm −2 in alkaline electrolytes. The assembled rechargeable zinc–air batteries (ZABs) incorporating Co 0.66 Ni 0.34 @Fe─N─C cathode exhibits a charge–discharge voltage gap comparable to the Pt/C||IrO 2 assembly and high robustness for over 60 h at 20 mA cm −2 .
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2023
·
IF 8.6
Youpu Zhao,Qing Sun,Jian Zhang,Jiawei Sheng
In this study, natural porous diatomite was utilized as a conciliatory carrier for the fabrication of Fe/N/C nano-clusters with assistance of binary molten salt of NaCl-ZnCl 2 under different annealing temperature and used to removal of norfloxacin (NFA). The sample Fe/D m900 (prepared at 900 °C) exhibited a high surface area and great catalytic performance for antibiotics in the presence of PMS. Over 97% NFA can be decomposed within 5 min and the final degradation rate reached 98%. Meaningfully, high-efficiency Fe/D m900 -PMS system was nearly impervious to pH values and inorganic cations in aqueous solution and could be a likely candidate for degradation of multiple contaminants in pharmaceutical outlet water. Furthermore, the other impacting variables such as catalyst dosage, PMS dosage, NFA concentration and initial pH were moreover explored towards debasement, and conceivable degradation pathways of NFA were presented through LC-MS. This work builds up a compelling procedure to synthesize super-dispersed Fe clusters, which may be amplified to other transition metal-based catalyst via molten salt.
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
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2021
·
IF 5.816
Zhaoxu Li,Xinyi Luo,Meifang Luo,Yuan Qin,Chaozhong Guo,Yao Liu,Zhongli Luo
To design inexpensive carbon catalysts and enhance their oxygen reduction reaction (ORR) activity is critical for developing efficient energy-conversion systems. In this work, a novel Fe-N-C hybrid electrocatalyst with carbon nanolayers-encapsulated Fe 3 O 4 nanoparticles is synthesized successfully by utilizing the molecular-level confinement of graphitic C 3 N 4 structures via hemin biomaterial. Benefiting from the Fe-N structure prevalent on the carbon nanosheets and large mesopore-dominated specific surface area, the synthesized catalyst under optimized conditions shows excellent electrocatalytic performance for ORR with an E ORR at 1.08 V versus reversible hydrogen electrode (RHE) and an E 1/2 at 0.87 V vs. RHE, and outstanding long-term stability, which is superior to commercial Pt/C catalysts (E ORR at 1.04 V versus RHE and E 1/2 at 0.84 V versus RHE). Moreover, the low hydrogen peroxide yield (<11%) and average electron transfer number (~3.8) indicate a four-electron ORR pathway. Besides, the maximum power density of the home-made Zn-air battery using the obtained catalyst is 97.6 mW cm −2 . This work provides a practical route for the synthesis of cheap and efficient ORR electrocatalysts in metal-air battery systems.
研究领域:
材料科学
·
能源化学
✓ 已验证
DOI
高影响因子
Industrial Chemistry & Materials
·
2024
·
IF 0
Jiayao Cui,Junyong Min,Hao Wang,Jianglan Shui,Lishan Peng,Zhenye Kang,Jieyuan Liu,Qingjun Chen,Shuo Bai,Yanrong Liu
Developing single-atom Fe–N4/C catalysts is crucial for the large-scale implementation of proton exchange membrane fuel cells (PEMFCs). While Fe–N4/C catalysts are inherently active in accelerating the slow ORR process, their performance is still inferior to that of Pt/C. Herein, a trace Co-doped Fe single-atom catalyst (Fe(tCo)–N–C) containing more active Fe2N8 sites has been synthesized. Interestingly, compared with typical FeN4 sites in an Fe–N–C electrocatalyst, the Fe2N8 sites generate a larger Fe–N bond length due to Co-doping. The elongated Fe–N bond in Fe2N8 lowers the d-band center and charge density of iron sites, enhancing the ORR process by facilitating the formation of *OOH and generation and desorption of *OH. Fe(tCo)–N–C manifested excellent acidic and alkaline ORR activity, with a half-wave potential (E1/2) of 0.80 V in HClO4 solution and 0.89 V in KOH medium. More importantly, high peak power densities (Pmax) were realized by applying Fe(tCo)–N–C in PEMFCs, with the Pmax reaching 890 mW cm−2 in H2–O2 and 380 mW cm−2 in H2–air. Additionally, trace Co dopants in the catalyst improved carbon graphitization and provided high ORR catalytic stability. This research introduces an innovative approach to engineering highly active Fe2N8 sites, providing valuable insights for the sustainable progress of PEMFC technology.
研究领域:
电化学
·
催化
·
能源材料
·
燃料电池
·
纳米技术
✓ 已验证
DOI
Environmental Science-Nano
·
2020
·Vol. 7
·期 12
·3814-3823
·
IF 7.683
Hanfeng Zhou,Zhibo Deng,Tianbao Liu,Tao Liu,Lijuan Zhang,Xintai Su,Zhang Lin
The science linking thermochemical conversion of large-scale industry oily sludge with applied materials has been improved in the last ten years. However, with the traditional converting methods it is hard to precisely control the composition and structure of oily sludge-based products during pyrolysis due to the complexity of the composition of the oily sludge. Here, a chlorinating calcination method using sodium chloride (NaCl) as a chlorinating salt and template was first developed to prepare porous Fe–N–C materials (FCN-500) through pyrolysis of oily sludge containing iron-bearing minerals and pyridine. The formation mechanism of FCN-500 was proposed, where iron ions (Fe3+) from the inorganic component (anorthite) in the sludge were rapidly dissociated with the assistance of NaCl, followed by coordination with the organic component (pyridine nitrogen) in the oily sludge to form the pyridine nitrogen–iron ((C5H6N)n–Fe) complex, and then carbonization. As-obtained FCN-500 exhibited higher specific capacitance (286.3 F g−1 at a current density of 0.5 A g−1), enhanced energy density (33.5 W h kg−1 at a power density of 606.1 W kg−1) and more excellent stability and durability (more than 80.1% capacitance retention after 10 000 cycles) compared with two other electrodes. The reasonably better performance of the obtained FCN-500 in supercapacitors (SCs) is attributed to its large surface area, hierarchically porous channels, high conductivity, and unique Fe–N–C structure. Therefore, this work not only provides a feasible way to solve the bottleneck problem in sludge pyrolysis, but also provides a method to design large scale porous Fe–N–C materials for practical applications.
研究领域:
环境科学
·
材料科学
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能源科学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）