CHEMICAL ENGINEERING JOURNAL
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2021
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IF 13.273
Meng Li,Zilong Li,Xiaolong Yu,Yinlong Wu,Cehui Mo,Mi Luo,Ligui Li,Shaoqi Zhou,Qiming Liu,Nan Wang,King Lun Yeung,Shaowei Chen
Development of low-cost, high-performance catalysts for the effective degradation of organic dyes is of both fundamental and technological significance for environmental remediation. Herein, FeN 4 -doped carbon nanotubes exhibit a remarkable catalytic activity towards the degradation of acid orange 7 (AO7) in the presence of peroxymonosulfate (PMS). This is accounted for by the abundant well-dispersed FeN 4 sites and appropriate adsorption energy. Radical quenching experiments and electron paramagnetic resonance measurements suggest that singlet oxygen is the main reactive oxygen species. 57 Fe Mossbauer spectroscopy measurements show that the FeN 4 moieties contain multiple spin states, and in conjunction with density functional theory calculations, confirm that FeN 4 with a low/medium spin state serves as the key sites for PMS activation and hence AO7 degradation. Results from this study highlight the critical role of spin states in FeN 4 in the generation of singlet oxygen for effective degradation of organic pollutants.
研究领域:
环境科学
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材料科学
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry A
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2023
·Vol. 11
·期 12
·6191-6197
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IF 11.9
Hongzhou Yang,He Huang,Qing Wang,Lu Shang,Tierui Zhang,Shouguo Wang
3d transition metal single atom catalysts (SACs) (e.g. M = Fe, Co, Cu) are considered as promising catalysts for oxygen reduction reaction (ORR), among which Fe SACs display comparable performance to commercial Pt/C. However, Fe SACs still demand significant improvements in activity and stability for further industrial deployment. Herein, a Fe, Cu dual metal SAC was synthesized using a facile ligand-mediated method. Fe and Cu atoms were atomically dispersed on commercial carbon black in the form of FeN4 and CuN4 sites. Owing to the interactions between the adjacent Fe and Cu atoms co-existing in a very tiny area, the as-synthesized Fe, Cu dual metal SAC exhibited excellent ORR performance with a high half-wave potential of 0.926 V and good stability in 0.1 M KOH, which are significantly higher than that of the Fe-SAC or Cu-SAC control samples. Density function theory calculations showed that the Cu single atom can act as an electron donator enriching the electron density of Fe sites, thus endowing the Fe sites with optimized adsorption/desorption energy for ORR intermediates and thereby facilitating the ORR activity of FeCu-SAC. Moreover, a study on three typical commercial carbon substrates indicated that carbon support with high surface areas and hierarchical pore structure was beneficial for ORR. The excellent ORR activity and durability of FeCu-SAC enabled the constructed Zn–air battery to have a high power density of 201.4 mW cm−2 and high specific energy of 827.68 W h kg−1.
研究领域:
材料科学
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催化化学
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能源科学
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产品关联
DOI
高影响因子
ChemElectroChem
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2020
·Vol. 7
·期 14
·3116-3122
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IF 4.154
Sheng Song,Xiaoming Zhang,Xinlong Xu,Chuchu Wu,Huanqiao Li,Zhangxun Xia,Shansheng Yu,Suli Wang,Gongquan Sun
Graphical Strat talks : The density of FeN x active sites is increased by co-doping with trace Cu atoms. The as-prepared 20Fe10Cu-NC electrocatalyst exhibits outstanding oxygen reduction reaction performance in both alkaline and acid conditions. Iron-nitrogen-doped carbon (Fe-NC) is an ideal candidate to replace Pt-based oxygen reduction reaction (ORR) electrocatalysts due to its low cost and comparably high intrinsic activity. To further enhance the ORR performance of Fe-NC electrocatalysts, efforts have been focused on two main methods. One is to enhance the intrinsic activity of FeN x sites through electronic and geometric regulation, and the other is to increase the density of active sites by introducing high-nitrogen-containing precursors or co-doping methods. Herein, we report a strategy to further increase the Fe loading through the introduction of a trace amount of Cu atoms. Significant enhancement of the electrocatalytic ORR property is observed in the as-prepared Fe and Cu co-doped electrocatalyst with superior half-wave potential (E 1/2 ) in both alkaline and acid electrolyte. Experimental and theoretical study reveals that the introduction of a trace amount of Cu atoms is beneficial for the formation of FeN 4 sites, owing to the reduced formation energy. This work opens up a wide avenue to further increase the Fe loading in Fe-NC electrocatalysts through bimetal co-doping method.
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
JOURNAL OF ALLOYS AND COMPOUNDS
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2023
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IF 6.2
Bin Hu,Yongqing Yang,Wei Cao,Xixi Wang,Chuan Zhou,Yiyang Mao,Lei Ge,Ran Ran,Wei Zhou
The high cost and unfavorable catalytic performance for oxygen reduction reaction (ORR) is one of the crucial obstacles that impede widely commercialization of proton-exchange membrane fuel cells (PEMFCs). Herein, we provide a novel, mass-producible ORR catalyst made of low-loading (10 wt%) Pt nanoparticles bound to patchy nitrogen-doped carbon (PNC) with uniformly dispersed FeN 4 sites (Pt/FeN 4 -PNC). The derived catalyst exhibits significantly improved catalytic activity and stability, obtaining a promising mass activity (MA) of 0.94 A mg pt −1 at 0.9 V (vs. RHE) with a negligible decay after 30,000 cycles accelerated durability test (ADT). In the fuel-cell assessment (under H 2 -Air conditions at 80 ℃), the Pt/FeN 4 -PNC and Pt/FeN 4 -PNC-10 g (scaled-up production) achieved peak power densities of 1.13 W cm −2 and 1.14 W cm −2 , respectively, and retained 88.5 % and 88.1 % of the initial values after 30,000 voltage cycles (0.60–0.95 V). The patchy structure of PNC substrate guarantees fast electron routes and resistance to corrosion. With the FeN 4 active sites in the PNC substrate, the oxygen molecules are concurrently reduced on the surfaces of the carbon substrate and Pt nanoparticles, thereby causing the ORR reaction zone on the catalyst layer to expand.
研究领域:
材料科学
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能源科学
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
MOLECULES
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2024
·Vol. 29
·期 23
·5561
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IF 4.2
Yuxuan Liu,Yufan Tan,Keyi Zhang,Tianqi Guo,Yao Zhu,Ting Cao,Haiyang Lv,Junpeng Zhu,Ze Gao,Su Zhang,Zheng Liu,Juzhe Liu
The catalyst is the pivotal component in CO2electroreduction systems for converting CO2into valuable products. Carbon-based single-atom materials (CSAMs) have emerged as promising catalyst candidates due to their low cost and high atomic utilization efficiency. The rational design of the morphology and microstructure of such materials is desirable but poses a challenge. Here, we employed different Mg(OH)2templates to guide the fabrication of two kinds of amorphous nitrogen-doped carbon nanosheet-supported Fe single atoms (FeSNC) with rough and flat surface structures. In comparison to flat FeSNC with saturated FeN4sites, the rough FeSNC (R-FeSNC) exhibited unsaturated FeN4−xsites and contracted Fe-N bond length. The featured structure endowed R-FeSNC with superior capacity of catalyzing CO2reduction reaction, achieving an exceptional CO selectivity with Faradaic efficiency of 93% at a potential of −0.66 V vs. RHE. This study offers valuable insights into the design of CSAMs and provides a perspective for gaining a deeper understanding of their activity origins.
研究领域:
材料科学
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催化化学
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能源化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Nano Energy
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2020
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IF 16.602
Jinwen Hu,Danyang Wu,Chao Zhu,Ce Hao,Cuncun Xin,Jiangwei Zhang,Jingya Guo,Nannan Li,Guifeng Zhang,Yantao Shi
Emerging heterogeneous catalysts with metal atomically dispersed on supports (tentatively termed single-atom catalysts, SACs) exhibit many appealing features in a wide variety of catalytic reactions , such as high activity and nearly 100% atom utilization. However, the synthesis of SACs currently requires not only multiple procedures but also appropriate precursors with special structures. Herein, the molten-salt assistance is presented as an effective means that enables the use of common metal oxides (such as Fe 2 O 3 and Co 2 O 3 ) and small organic molecules as precursors for the preparation of carbon-supported SACs through one-pot pyrolysis . Molten salts as templates that can be easily removed after synthesis also contribute to the formation of porous and nitrogen-doped carbon with a high specific area. More importantly, benefiting from the strong polarizing force of molten salts, the ionic bonds in oxides can be destabilized at high temperature. Subsequently, metal ions released from solid oxides are transformed into atomically dispersed active sites after being trapped by nitrogen (N) atoms on the carbon support. The as-prepared SAC with atomically dispersed Fe–N 4 sites demonstrates high activity, outstanding stability and good methanol tolerance in the oxygen reduction reaction (ORR) in both alkaline and acidic media.
研究领域:
催化
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材料科学
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化学工程
✓ 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）