Science Advances
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2025
·Vol. 11
·期 9
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IF 12.5
Mengxue Huang,Xuya Zhu,Wenwen Shi,Qianqian Qin,Jie Yang,Shanshan Liu,Lifang Chen,Ruimin Ding,Lin Gan,Xi Yin
Nitrogen-coordinated metal sites (MNx) in metal- and nitrogen-codoped carbon (M-N-C) catalysts offer promising electrocatalytic activity, but selective synthetic design of MNx sites with specific coordination environments remains challenging. Here, we manipulate the formation statistics of MNx sites by using sacrifice alkali metals (AM = Li, Na, and K) to form metal vacancy-Nx carbon (AM-MVNx-C) templates, which are used to direct the solution-phase formation of CoN4 sites in Co-N-C catalysts. We build a probability weight function based on the embedding energy of M in MNx sites as the descriptor for MNx formation statistics, and we predict that the alkali metals are prone to induce the formation of MVN4 sites. By coordinating Co2+ ions with AM-MVNx-C templates, we synthesize Co-N-C with CoN4 sites, demonstrating remarkable oxygen reduction activity in anion exchange membrane fuel cells. These results highlight the statistical thermodynamics of MNx formation and open up the possibility for the rational design of complex M-N-C electrocatalysts with well-defined MNx sites.
研究领域:
材料科学
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电化学
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产品关联
DOI
PubMed
高影响因子
NEW CARBON MATERIALS
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2022
·
IF 3.7
Hui-nian Zhang,Hui-qi Wang,Su-ping Jia,Qing Chang,Ning Li,Ying Li,Xiao-lin Shi,Zi-yuan Li,Sheng-liang Hu
Developing highly selective, economical and stable catalysts for the electrochemical conversion of CO 2 into value-added carbon products to mitigate both CO 2 emission and the energy crisis is challenging. We report an efficient and robust electrocatalyst for the CO 2 reduction reaction (CO 2 RR) by embedding CoN 4 active sites in a graphene matrix. These highly dispersed CoN 4 sites show an extraordinary CO 2 RR activity, with a high CO Faradaic efficiency of nearly 95% at −0.76 V (vs. RHE) and remarkable durability. The corresponding overpotential is 0.65 V. Our finding could pave the way for the design at the atomic scale of highly efficient electrocatalysts for the CO 2 RR.
研究领域:
材料科学
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环境科学
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电化学
✓ 已验证
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2025
·
IF 9.7
Yihang Xue,Dahai Zeng,Yuying Meng,Bing Du,Haifang Xie,Lei Ma,Yufeng Wang,Qingsheng Gao
Atomic transition metal-nitrogen (M-N x ) active sites dispersed on carbon matrix have emerged as highly promising electrocatalysts for energy conversion systems, owing to their maximized metal center utilization and excellent conductivity of the carbon substrate. However, conventional symmetric M-N 4 configurations often exhibit limited hydrogen evolution reaction (HER) activity in alkaline due to the inferior water dissociation capacity. In this work, isolated Co single atoms anchored on N -doped hollow carbon substrates (Co SA /NHCs) are successfully fabricated by the pyrolysis of Co 2+ -containing polypyrrole (Co-PPY) precursor, and the subsequent removal of embedded Co particles. Thanks to the high density of atomically distributed asymmetric Co-N 4 moieties, which facilitate efficient water activation and optimal adsorption of the active hydrogen (H*), the synthesized Co SA /NHCs electrocatalysts show remarkable HER activity and stability in alkaline electrolyte. Besides, they can effectively electrolyze HER in acidic medium, undergoing the Volmer-Heyrovsky pathway. Remarkably, Co SA /NHC-800, pyrolyzed at 800 °C, requires small overpotentials of 230 and 228 mV to achieve the current density of −10 mA cm −2 in 1.0 M KOH and 0.5 M H 2 SO 4 solutions, respectively. Moreover, it displays small Tafel slopes, high Faradic efficiencies (∼100 %) and superior long-term stability. This study paves a strategic approach for designing high-performance single-atom electrocatalysts through asymmetric structural engineering.
研究领域:
材料科学
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电化学
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产品关联
DOI
PubMed
高影响因子
ANALYTICA CHIMICA ACTA
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2022
·
IF 6.911
Hui Ouyang,Hongwei Yuan,Junyi Huang,Jiaxin Xian,Wenwen Wang,Zhifeng Fu
In view of the optimal catalytic efficiency (∼100%), single-atom site catalysts are being widely exploited in a range of areas including organic synthesis, energy conversion, environmental remediation, biotherapy, etc. However, low loading ratio of the unitary active sites on single-atom site catalysts dramatically hinders the remarkable improvement of their catalytic activity . Hereby, a facile low-temperature reduction protocol was adopted for synthesizing CoN 4 -supported Co 2 N metal clusters on graphitic carbon nitride , which show the remarkably superior chemiluminescent (CL) catalytic capacity than some reported pure single-atom site catalysts. Nitrogen-encapsulated Co 2 N clusters coupled with isolated Co–N 4 moieties (Co 2 [email protected] –N 4 ) endowed the synergetic catalysts with high Co content of 53.2 wt%. Through X-ray absorption spectroscopy, the synergetic active sites (Co 2 [email protected] –N 4 ) afforded the CoN 4 -supported Co 2 N clusters with the remarkable catalytic activity for accelerating the decomposition of H 2 O 2 to produce extensive superoxide radical anion rather than singlet oxygen or hydroxyl radical . Therefore, the CoN 4 -supported Co 2 N clusters possessed the superb enhancement effect on luminol-H 2 O 2 CL reaction by ∼22829 times. The CoN 4 -supported Co 2 N clusters were utilized as signal probes to establish a CL immunochromatographic assay (ICA) platform for quantitating mycotoxins . Herein, aflatoxin B1 was employed as a mode analyte and the limit of detection was as low as 0.33 pg mL −1 (3σ). As a proof-of-principle work, the developed ICA protocol was successfully employed on the detection of aflatoxin B1 spiked in Angelica dahurica and Ganoderma lucidum with acceptable recoveries of 84.0–107.0%. The ideal practicability of the work elucidates that CoN 4 -supported Co 2 N clusters showed a new perspective for developing the sensitive CL biosensing.
研究领域:
分析化学
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材料科学
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生物化学
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食品安全
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产品关联
DOI
PubMed
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2026
·
IF 19.7
Guoyan Dang,Kaikai Zhang,Xin Zhong,Haoran Hu,Xiaoguang Wang,Youke Yan,Yue Wang,Yanrong Zhang
Co-N 4 /C O dual sites enable relay catalysis in sulfite-based AOPs. • C O sites initiate radical chains via strong p-p hybridization with sulfite. • Co-N 4 sites promote the conversion of SO 5 •− to SO 4 •− through d-p coupling. • Flow, real wastewater, and ecotoxicity tests confirm practicality. Sulfite-based advanced oxidation processes (S(IV)-AOPs) have emerged as a promising persulfate-free and low-toxicity route for sulfate radical (SO 4 •− ) generation. However, the radical-chain nature of S(IV) oxidation, involving both SO 3 •− initiation and the subsequent conversion of SO 5 •− to SO 4 •− , makes it difficult for single-site catalysts to simultaneously achieve efficient chain initiation and downstream radical conversion. Here, we report a carbon-supported Co-N 4 /C O bifunctional catalyst that establishes a dual-site relay catalysis strategy for S(IV)-AOPs. In this architecture, spatially separated yet electronically coupled sites exhibit a clear division of labor: ketonic C O groups serve as primary activation sites for S(IV) activation to generate SO 3 •− via p-p hybridization, whereas adjacent Co-N 4 moieties act as relay sites to facilitate the conversion of SO 5 •− to SO 4 •− through d-p coupling. In situ spectroscopy, selective site-masking experiments, open-circuit potential measurements, and density functional theory calculations collectively verify this stage-specific activation-conversion relay mechanism. As a result, the Co-N 4 /C O catalyst achieves a 10.36-fold higher apparent rate constant for metronidazole degradation than its single-site Co-N 4 counterpart. Moreover, the catalytic system exhibits robust stability in continuous-flow operation and real wastewater treatment while maintaining low ecotoxicity. This work provides a strategy for radical-chain regulation in S(IV)-AOPs. Download: Download high-res image (264KB) Download: Download full-size image
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DOI
高影响因子
Polymers
·
2018
·Vol. 10
·期 12
·1339
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IF 2.935
Yuanhai Chen,Fengru Liu,Feng Qiu,Chenbao Lu,Jialing Kang,Doudou Zhao,Sheng Han,Xiaodong Zhuang
Cobalt-doped graphene-coupled hypercrosslinked polymers (Co-GHCP) have been successfully prepared on a large scale, using an efficient RAFT (Reversible Addition-Fragmentation Chain Transfer Polymerization) emulsion polymerization and nucleophilic substitution reaction with Co (II) porphyrin. The Co-GHCP could be transformed into cobalt-doped porous carbon nanosheets (Co-GPC) through direct pyrolysis treatment. Such a Co-GPC possesses a typical 2D morphology with a high specific surface area of 257.8 m2g−1. These intriguing properties of transition metal-doping, high conductivity, and porous structure endow the Co-GPC with great potential applications in energy storage and conversion. Utilized as an electrode material in a supercapacitor, the Co-GPC exhibited a high electrochemical capacitance of 455 F g−1at a specific current of 0.5 A g−1. After 2000 charge/discharge cycles, at a current density of 1 A g−1, the specific capacitance increased by almost 6.45%, indicating the excellent capacitance and durability of Co-GPC. These results demonstrated that incorporation of metal porphyrin into the framework of a hypercrosslinked polymer is a facile strategy to prepare transition metal-doped porous carbon for energy storage applications.Keywords:transition metal-doping;porous carbon;hypercrosslinked polymer;two-dimensional nanosheet;supercapacitor
研究领域:
材料科学
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能源存储与转换
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产品关联
DOI
PubMed
高影响因子
Energy Storage Materials
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2022
·
IF 20.831
Huan Yang,Shuai Gao,Dewei Rao,Xiaohong Yan
Developing cost-effective and high-efficient bifunctional electrocatalyst for both oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) is essential for rechargeable Zn-air battery application. However, achieving high-active dual sites for bifunctional oxygen electrocatalysis in a single catalyst, as well as determining the decisive active sites for OER and ORR to explore the synergistically catalytic mechanism remain challenges. Herein, we propose a catalyst consisting of high-purity pyrrole nitrogen anchored cobalt single-atom (CoN 4 ) and adjacent metallic cobalt sites (Co p @CoNC) for explicit research of dominated active sites. The obtained Co p @CoNC exhibits superior electrocatalytic activity with a small overpotential difference of 0.68 V between OER potential at 10 mA cm −2 and ORR half-wave potential, outperforming commercial noble-metal based catalysts. Electrochemical measurements and theoretical simulations verify the pyrrole-type CoN 4 and adjacent metallic cobalt are separately decisive active sites for ORR and OER activities. Simultaneously, metallic cobalt regulates electron distribution of CoN 4 moiety to improve ORR activity. Importantly, the rechargeable liquid and flexible solid-state Zn-air batteries using Co p @CoNC as air electrode catalysts possess high peak power densities of 188.8 and 121.8 mW cm −2 , respectively. Our findings provide a feasible strategy to design high-performance multifunctional catalysts for rechargeable Zn-air batteries application.
研究领域:
材料科学
·
电化学
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产品关联
DOI
高影响因子
CHINESE JOURNAL OF CATALYSIS
·
2024
·
IF 15.7
Yuan Jiang,Ji Yang,Mu-Lin Li,Xue-Jia Wang,Na Yang,Wei-Ping Chen,Jin-Chao Dong,Jian-Feng Li
ABSTRACT Metal-nitrogen-carbon single-atom catalysts (M-N-C SACs) have emerged as a highly promising material for ammonia synthesis from electrocatalytic nitrate reduction due to their isolated metal site and capacity to prevent the N–N coupling. However, understanding the structure-activity relationship at molecular level remains challenging because of the inhomogeneous M N x structure presented in current synthesized M-N-C catalysts. In this study, we utilized metal phthalocyanine ( M Pc) as a model platform catalyst containing a uniform and well-defined M N 4 center to unravel their intrinsic activity tendency toward ammonia synthesis from nitrate reduction, both experimentally and theoretically. Our experimental results exhibit a significant activity difference for ammonia production in the order of FeN 4 > CuN 4 > NiN 4 > MnN 4 > CoN 4 > ZnN 4 , and among which the FeN 4 site delivers much higher faradic efficiency and the highest turnover frequency of 83.3% and 4395.2 h –1 at –1.0 V vs . RHE, respectively. Density-functional theory calculations indicates that, compared to CoN 4 and MnN 4 , the FeN 4 site not only has appropriate adsorption strength for NO x intermediate species, but also has certain inhibitory effects on hydrogen evolution reaction process. These findings provide systematic and reliable guidance for catalyst synthesis toward nitrate reduction to NH 3 from both the experimental and computational perspectives.
研究领域:
催化
·
电化学
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材料科学
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理论化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）