Journal of Environmental Chemical Engineering
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2022
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IF 7.968
Liuqun Fan,Zhiyan Hou,Tianbao Liu,Xiangjing Liang,Andrei Ivanets,Kongjun Ma,Xintai Su
Heteroatom-doped carbon materials derived from oil-bearing sludge exhibit excellent supercapacitor performance due to their unique electronic and chemical properties. However, the complex composition of heteroatoms in oil-bearing sludge makes it difficult to achieve sufficient and directional doping by direct pyrolysis . In this paper, an oleic acid pretreatment-roasting-secondary activation strategy was developed to make full use of hydrocarbons, iron- and nitrogen-containing compounds in oil-bearing sludge to prepare Fe-N X -C materials with excellent electrochemical properties. Characterization results such as transmission electron microscopy (TEM) and N 2 adsorption analysis showed that the best sample had a hierarchical pore structure and uniform Fe and N element loading. X-ray photoelectron spectroscopy (XPS) analysis found that the addition of oleic acid can promote the formation of Fe-Nx, and the dosage of oleic acid will affect the content of Fe-Nx in the carbon materials. Electrochemical characterization of this supercapacitor material was conducted. The best sample's specific capacitance was as high as 293.6 F g −1 at the current density of 0.5 A g −1 , and the capacitance retention rate could still reach 71.5% at the current density of 10 A g −1 . The assembled button-type symmetrical supercapacitors had an energy density of 8.68 Wh kg −1 and a power density of 137.53 W kg −1 , which is much higher than those of most other waste-based carbon materials. This work presents a new idea for the preparation of heteroatom doped carbon materials with excellent capacitive properties from oily sludge, which provides a new reference for the treatment and resource utilization of oily sludge.
研究领域:
环境科学
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材料科学
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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
Junjie Cheng,Xinman Tu,Pengxuan Wu,Rentao zhou,Shaohua Luo,Li Zhang,Jianping Zou,Yanhong Li,Hannah M. Johnson,Qiang Zhang
In the reaction systems involving peroxymonosulfate (PMS) activation, the degradation of organic pollutants is influenced by the distinct roles played by the oxidation of free radicals and non-free radicals. The synergistic effect resulting from both oxidation pathways is often more efficient compared to a single oxidation pathway, as it allows for the optimal utilization of oxidation capacity and adaptation to complex reaction environments. Nitrogen-doped carbon substrates hosting single-atom catalysts (SACs) are anticipated to serve as an optimal platform for managing the dual oxidation pathways in the PMS activation reaction. This is attributed to the availability of numerous reaction sites that meet the activation requirements. However, there's a lack of substantial reports on this subject. Herein, we synthesized a series of single-atoms Fe nitrogen-doped carbon catalysts with different coordination structures by adjusting the coordination numbers between Fe and N atoms. It is used to investigate the reaction pattern of PMS over SACs, so as to enhance the catalytic efficacy of SACs through distinct coordination structures. The experimental and theoretical results indicate that PMS functions as both an electron receiver and provider on FeN x /C catalysts. Moreover, the specific arrangement of the Fe-N-C structure influences the exchange of electrons between the catalysts and PMS. Hence, the co-oxidation pathway of free radicals ( OH, SO 4 − and O 2 − ) and non-free radicals ( 1 O 2 ) can be modulated by altering the coordination number of Fe and N atoms during PMS activation. The elimination efficiency of tetracycline hydrochloride was significantly enhanced due to the abundance of both free radical and non-free radical species generated in the FeN 3 /C/PMS reaction system, exhibiting a degradation kinetic constant of 0.564 min −1 . In addition, it showed promising potential for application in practical wastewater degradation, exhibiting high anti-interference to general environmental disturbances (such as humic acid, chloride ions, bicarbonate ions and nitrate ions).
研究领域:
环境科学
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催化化学
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产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2021
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IF 5.316
Lei Cao,Maliang Zhang,Kunmei Su,Feng Gu,Zhenhuan Li
Decorating porous carbon nanomaterials with rich homodispersed metal cluster and heteroatoms can effectively shorten the diffusion pathway of oxygen and expose more active sites, thereby promoting oxygen reduction reaction (ORR). Herein, hierarchical porous carbon nanorods with homodispersed Fe–N x –C active sites are obtained by calcination , etching and ammonia activation of Fe-nitrogenous acid (NTA) coordination polymer nanowires. The obtained Fe-PCNRs-700 as ORR catalysts show the excellent activity with half wave potential (E 1/2 ) of 0.71 V vs. reversible hydrogen electrode (RHE) in 0.5 M H 2 SO 4 and 0.87 V vs. RHE in 0.1 M KOH electrolyte, which owe to its huge specific surface area (1652 m 2 g −1 ), hierarchical pore structure , homodispersed Fe–N x –C active sites and structural defects. Furthermore, using Fe-PCNRs-700 as a cathode catalyst in both liquid and flexible solid Zn-air batteries, and the assembled liquid batteries display the high power density of 161 mW cm −2 and robust charge/discharge stability of 116 h.
研究领域:
材料科学
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电化学
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
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2021
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IF 9.229
Guang Li,Juan Yang,Yulian Chen,Min Liu,Xiaowei Guo,Gairong Chen,Baobao Chang,Tianjing Wu,Xianyou Wang
Looking for a high-efficiency, durabile, and low-cost dual-functional oxygen electrocatalyst as the air electrode catalyst in rechargeable zinc-air batteries (ZABs) is urgently desirable but faces many challenges. Herein, we propose the preparation strategy of effectively using a bifunctional electrocatalyst (Fe–Nx/C) based on the zeolite imidazole organic framework-8 (ZIF-8) as the template agent, with surface modification coated by ferrocene (Fc) molecules followed by pyrolysis at high temperature under inert atmosphere. Benefiting from the surface modification of ZIF-8 with Fc molecules, more abundant multiple catalytic Fe/Fe–Nx/FeCx sites with high intrinsic activity are derived, the resultant Fe–Nx/C exhibits excellent potential gap (ΔE = 0.63 V) and durability, which is obviously superior to the Pt/C + IrO2 benchmark (ΔE = 0.77 V) and other state-of-the-art electrocatalysts. Furthermore, the assembled rechargeable ZABs employing the Fe–Nx/C as an air-electrode show a reduced charging–discharging potential difference of 0.603 V, high power density of 214.8 mW cm–2, and long-term cycling stability of more than 290 h at 2.0 mA cm–2. Therefore, this work presents a feasible strategy to prepare a high-efficiency and durability ORR/OER bifunctional electrocatalyst toward high performance ZABs and next-generation energy storage devices.
研究领域:
材料科学
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电化学能存储与转换
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产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
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2021
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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
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
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2018
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IF 4.229
Ya Chu,Lin Gu,Hongmei Du,Konggang Qu,Yan Zhang,Jinsheng Zhao,Yu Xie
In this study, we synthesized a nitrogen rich compound (FPPHA) as the precursor of oxygen reduction reaction (ORR) catalysts, which was prepared based on 1,10-phenanthroline-5-amine and 2,2’-bipyridyl-5,5’-dialdehyde. The FPPHA-Fe complex was formed and be loaded on the carbon powder to form the FPPHA-Fe/C composite catalyst. The pyrolysis of the FPPHA-Fe/C composite was conducted at different temperatures, including 700 °C, 800 °C, and 900 °C, and the resultant pyrolyzed materials were designated to FPPHA-Fe/C-700, FPPHA-Fe/C-800, FPPHA-Fe/C-900, respectively. The physical characteristics of the catalysts were examined by powder X-ray diffraction (PXRD), Brunauer–Emmett–Teller analysis, X-ray photoelectron spectrometer (XPS) and scanning electron microscopy (SEM) etc. The ORR performance of the composite catalysts were evaluated by cyclic voltammetry (CV), linear sweep voltammetry (LSV), and rotating ring disk electrodes (RRDE) in an alkaline solution. The results suggested that the pyrolysis process has a positive effect on the ORR activity of the catalysts, and among the catalysts the Fe-FPPHA/C-800 had the most preferable performance, which reduces oxygen through a predominantly four electron pathway with an average electron transfer number of 3.86 and an average hydrogen peroxide yield of 6.7%.
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
Green Energy & Environment
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2020
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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
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纳米技术
✓ 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）