MICROPOROUS AND MESOPOROUS MATERIALS
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2019
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IF 4.182
Junmei Luo,Shufeng Bo,Qingda An,Zuoyi Xiao,Haisong Wang,Weijie Cai,Shangru Zhai,Zhongcheng Li
Rational design of ordered catalytic composites with high performance and facile preparation method for environmental remediation still remains a tremendous challenge. For this vision, ordered composites with confined cobalt intercalated N/C layers (Co–N/C) were successfully prepared via carbonizing a mixture of cobalt species, histidine (His) and zirconium-containing SBA-15 (ZS) utilizing a simple non-solvent method. Taking the confinement effect and inherent hydrophilic groups (Si–OH) of mesoporous silica as the foothold, the strong Co 2+ /N or Co 2+ /O coordination (Co 2+ (–COO - or –NH 2 ) 2 and Co 2+ (–O - ) 2 ) and silica/His or His/His adhesive/cohesive interactions endowed the Co-based catalyst with optimal interfacial properties , cycling stability and magnetic separability for degradation of several pollutants (phenol, antibiotics and dyes). The degradation efficiency of Co@NC-ZS-700 for bisphenol A was superior to Co-ZS-700, NC-ZS-700 and Co@NC-SBA-700 due to the flaky structure with confined Co–N/C layers, which could achieve 95.0% within 20 min. In addition, the catalyst could still degrade more than 84.4% bisphenol A after five consecutive reactions. Based on the characterization analysis, tested active species (SO 4 •– , • OH and 1 O 2 ) and degradation products, double-process activation mechanism and degradation pathways were plausibly proposed (radical and non-radical processes). Additionally, various influencing factors, including carbonization temperature, amount of cobalt species, peroxymonosulfate (PMS)/catalyst dosage, pH value, coexisting ions and real water environment, were also systematically studied. This work might pave a feasible way for contaminant treatment utilizing ordered mesoporous silica composites with diffusion promoted channels involved under aqueous systems.
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DOI
高影响因子
Journal of Energy Chemistry
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2019
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IF 5.162
Bo Lv,Sha Zeng,Wei Yang,Jian Qiao,Chao Zhang,Chengfeng Zhu,Minghai Chen,Jiangtao Di,Qingwen Li
Recently, the development of high-performance bifunctional oxygen catalysts integrated with flexible conductive scaffolds for rechargeable metal-air batteries has attracted considerable interest, driving by fast-growing wearable electronics . Herein, we report a flexible bifunctional oxygen catalyst thin film consisting of Co–N–C bifunctional catalysts embedding in carbon nanotube (CNT) networks. The catalyst is readily prepared by pyrolysis of cobalt-based zeolitic imidazolate frameworks (ZIF-67) that are in-situ synthesized in CNT networks. Such catalyst film demonstrates very high catalytic activities for oxygen reduction (onset potential: 0.91 V, and half-wave potential: 0.87 V vs. RHE) and oxygen evolution (10 mA cm −2 at 1.58 V) reactions, high methanol tolerance property, and long-term stability (97% current retention). Moreover, our integrated catalyst film shows very good structure flexibility and robustness. Based on the obtained film air electrodes, flexible Zn–air batteries demonstrate low charging and discharging overpotentials (0.82 V at 1 mA cm −1 ) and excellent structure stability in the bending tests . These results indicate that presently reported catalyst films are potential air electrodes for flexible metal–air batteries.
研究领域:
材料科学
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电化学
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纳米能源
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先进功能材料
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可再生能源
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高影响因子
CRYSTAL GROWTH & DESIGN
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2026
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IF 3.6
Tao Niu,Wenju Gu,Youwen Wang,Bin Gao,Wingkei Ho,Dingze Lu
To address the high energy consumption and low efficiency associated with traditional ammonia synthesis, we developed a nickel-doped cobalt-based bimetallic catalyst (CoNi-NC) derived from ZIF-67 for the efficient electrocatalytic reduction of nitric oxide (NO) to ammonia (NORR). The CoNi-NC-x catalyst, which features cobalt nanoparticles measuring 5–10 nm on a carbon support, was synthesized by introducing Ni2+ ions into ZIF-67 followed by vacuum pyrolysis. The incorporation of nickel optimized the electronic configuration of cobalt, maintained a high specific surface area, and improved the distribution of active sites. Electrochemical tests indicated that CoNi-NC-2 achieved an ammonia production rate of 19.7 μmol cm–2 h–1 and a Faraday efficiency of 15.8% at −1.0 V vs. RHE, outperforming Co-NC. Additionally, the catalyst exhibited excellent stability. The Zn-NO battery utilizing this catalyst facilitated the synergistic removal of NO, ammonia synthesis, and power generation, achieving a peak power density of 1.34 mW cm–2 and an open-circuit voltage of 1.91 V. Density functional theory calculations revealed that nickel doping reduced the d-band center of cobalt, weakened NO adsorption, and activated the N–O bond, thereby enhancing NORR activity.
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高影响因子
Fundamental Research
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2022
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IF 0
Feng Ma,Xuan Liu,Xiaoming Wang,Jiashun Liang,Jianyu Huang,Cameron Priest,Jinjia Liu,Shuhong Jiao,Tanyuan Wang,Gang Wu,Yunhui Huang,Qing Li
Transition metal supported N-doped carbon (M-N-C) catalysts for oxygen reduction reaction (ORR) are viewed as the promising candidate to replace Pt-group metal (PGM) for proton exchange membrane fuel cells (PEMFCs). However, the stability of M-N-C is extremely challenging due to the demetalation, H 2 O 2 attack, etc. in the strongly oxidative conditions of PEMFCs. In this study, we demonstrate the universal effect of Zn on promoting the stability of atomically dispersed M-N x /C (M = Co, Fe, Mn) catalysts and the enhancement mechanism is unveiled for the first time. The best-performing dual-metal-site Zn-Co-N-C catalyst exhibits a high half-wave potential ( E 1/2 ) value of 0.81 V vs. reversible hydrogen electrode (RHE) in acid and outstanding durability with no activity decay after 15,000 accelerated degradation test (ADT) cycles at 60 °C, surpassing most reported Co-based PGM-free catalysts in acid media. For comparison, the Co-N-C in the absence of Zn suffers from a rapid degradation after ADT due to the demetalation and higher H 2 O 2 yield. X-ray adsorption spectroscopy (XAS) and density functional theory (DFT) calculations suggest the more negative formation energy (by 1.2 eV) and increased charge transfer of Zn-Co dual-site structure compared to Co-N-C could strength the Co-N bonds against the demetalation and the optimized d-band center accounts for the improved ORR kinetics.
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INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2023
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IF 8.2
Lin Zhang,Jili Yuan,Qinqin Xu,Fazhi Zhang,Qi Sun,Haibo Xie
Noble-Metal-Free nitrogen-doped carbon-based materials are promising electrocatalysts for oxygen reduction reaction (ORR), yet it remains a great challenge to construct efficient porous non-noble metal nitrogen-doped carbon (M-N-C) catalysts with uniform distribution, due to the easy aggregation of metals. Herein, we reported the synthesis and assessment of a novel and efficient noble-metal-free catalyst for oxygen reduction reaction (ORR) from pyrolysis of a cobalt-containing cellulosic poly(ionic liquid) (Co-N-C). The prepared Co-N-C catalyst possesses high surface area , hierarchical porous structure, well-dispersed Co nanoparticles and large amounts of low-coordinated Co active sites. Especially, the Co-N-C-850 sample exhibits a high ORR activity (E onset = 0.827 V, E 1/2 = 0.74 V) that can rival 20 wt% commercial Pt/C (E onset = 0.833 V, E 1/2 = 0.71 V) in alkaline media. Moreover, the Co-N-C-850 sample also shows excellent anti-methanol poisoning activity and long-term stability toward ORR compared with commercial Pt/C. Our study provides a promising avenue both for the development of non-noble M-N-C catalysts for fuel cells and the functional utilization of cellulose .
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DOI
PubMed
高影响因子
CARBON
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2018
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IF 7.082
Hao Mei,Mengran Yang,Yanfei Shen,Fei He,Zhixin Zhou,Xinghua Chen,Yiran Yang,Songqin Liu,Yuanjian Zhang
The efficient and low-cost platinum group metal (PGM)-free metal-nitrogen-carbon electrocatalysts (M-N-C) are potential alternatives for the oxygen reduction reaction (ORR) in artificial energy conversion devices. However, the solid-state reactions of M/C/N-containing precursors at high temperature was rather complicated, making the engineering of carbonization processes of M-N-C catalysts challenging and less explored. Herein, we report a way to modulate the pyrolysis processes of M-N-C by pre-organization of the molecular precursors via a simple solvation , in which, the simultaneous hydrogen bonding and coordination interactions played an important roles. It was revealed that the supramolecular precursors from different solvents had the same chemical compositions but quite different crystal structures. Accordingly, the pyrolysis processes were greatly altered, making the as-prepared Co-N-C exhibit distinct morphologies ranging from worm-nanotubes to bamboo-nanotubes and to porous nanosheets . The optimized Co-N-C showed competitive bifunctional electrocatalytic ORR and OER activities, which were further successfully applied to advance the rechargeable Zn–air batteries with excellent cycling stability over 600 h at a current density of 20 mA cm −2 and voltage gap (0.76 V). This work highlights the great potential of the pre-organization for the designing and selecting of precursors to engineer pyrolyzed M-N-C with higher electrocatalytic activities .
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高影响因子
Molecular Catalysis
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2018
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IF 0
Shanshan Jie,Congqiang Yang,Yuan Chen,Zhigang Liu
The highly dispersed active sites are desirable to optimize the atom efficiency. In this study, a series of novel cobalt grafted in N-doped carbon (Co-N-C) catalysts for selective oxidation of ethylbenzene are synthesized by heating a solution of cobalt porphyrin and peptides in ionic liquids, which are also characterized by techniques such as FT-IR, XRD, SEM-EDX, HR-TEM, and XPS. The results show that the as-prepared catalysts have an attractive catalytic performance, namely, 40% of ethylbenzene conversion and 75% of selectivity to acetophenone. Especially, the activity and selectivity of the as-prepared catalysts remain almost similar even after the 10th run. Moreover, the modified-complexometry method is verified to improve the dispersion of metal active sites. The remarkable catalytic performance of the as-prepared catalysts is attributed to the highly dispersed active sites and strong interactions between Co and N species in Co-N x moieties.
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CHEMICAL ENGINEERING JOURNAL
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2024
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IF 13.3
Xue Liu,Wei Yan,Jie Song,Hao Song,Wenmiao Chen,Yuexing Zhang,Yanli Chen
Enhancing the exposure of active sites and optimizing the electronic structure of the catalysts are indispensable for efficient catalyst design, yet remains challenging in the renewable energy field. Herein, a sequential pyrolyzing and phosphating approach for a well-designed GO/CoTPP gel precursor has been explored to prepare a Co-based carbon catalyst containing single-atom Co-N x and hollow Co 2 P active species (Co 2 P/Co-N-C) for multifunctional electrocatalytic reactions. Kirkendall effect occurring during the template-free one-pot phosphating approach induced the formation of the hollow Co 2 P structure in the catalyst, simultaneously optimizing the electron structure and allowing the active sites to be exposed to a greater extent. DFT calculations demonstrated that the Co 2 P and Co-N x structures enable Co 2 P/Co-N-C to have a suitable d-band center depending on the electron transfer from Co 2 P to Co-N x , which enhances the adsorption of O* and the dissociation of OH* in oxygen electrode reactions, thereby facilitates catalytic reactions. As a result, the Co 2 P/Co-N-C exhibits excellent trifunctional activity with a half-wave potential of 0.89 V in alkaline for oxygen reduction reaction (ORR), overpotentials of 330 mV for oxygen evolution reaction (OER) and 190 mV for hydrogen evolution reaction (HER), respectively, which are among the best results reported to date for Co-containing carbon-based catalysts. Furthermore, the flexible Zinc-air battery with Co 2 P/Co-N-C electrodes also demonstrates a high open circuit voltage of 1.35 V, which is applied to build the self-powered device for water splitting continuously. Our work provides a facile strategy to prepare high-performance trifunctional catalysts by morphology/structure control of metal-based NPs on carbon-based materials.
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高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2022
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IF 6.371
Yiting Bu,Jiaxi Liu,Dan Cai,Pengru Huang,Sheng Wei,Xiaoshuang Luo,Zhaoyu Liu,Fen Xu,Lixian Sun,Xueying Wei
NaBH 4 (10.8 wt% theoretical hydrogen storage capacity) is an ideal hydrogen carrier, but its hydrolysis reaction at room temperature requires high-efficiency catalysts for activation and acceleration. Structured catalysts can effectively inhibit metal particle agglomeration . However, metal particles fall off the surface of the support during testing. Therefore, we report a magnetic recyclable hollow shell material H-Co/N/C-Ru@C-T. The dual protection of carbonized ZIF-67 as a framework and surface-coated carbon film makes it show good catalytic activity and durability in NaBH 4 hydrolysis reaction. The hydrogen generation rate (HGR) is as high as 9815.82 mL H2 min −1 g −1 , and the activation energy ( E a ) is reduced to 26.9 kJ mol −1 . Moreover, it retains 81.3% of its initial catalytic activity even after 25 hydrolysis cycles. Through a series of characterization, such as electron scanning spectroscopy and inductively coupled plasma atomic emission, the improvement effect of using hollow Co/N/C as framework and coating carbon film on surface on the catalytic activity and durability of H-Co/N/C-Ru@C-650 is systematically revealed. We believe this work is of unusual significance on exploring novel hydrogen storage material catalysts, especially providing opportunities for the improvement of catalytic activity and durability of catalysts.
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高影响因子
ANALYST
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2022
·Vol. 147
·期 5
·915-922
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IF 5.227
Jian Chen,Song Hu,Yongliang Cai,Xia Liu,Yueqi Wu,Yihu Dai,Zhijuan Wang
Nanozymes have attracted considerable attention as a new type of promising artificial enzyme in recent years. Here, an oxidase-like cobalt–nitrogen–carbon (Co–N/C-900) nanozyme with well-regulated metal atom spatial distribution has been derived from Co–Zn bimetal zeolitic imidazolate framework precursors and used to develop a facile colorimetric sensing method for L-cysteine. With the aid of Co–N/C-900, the colorless 3,3′,5,5′-tetramethylbenzidine (TMB) was oxidized to blue oxidized TMB in the absence of H2O2. However, the oxidation was inhibited after the addition of L-cysteine, and the blue color faded to colorless. Thus, Co–N/C-900 exhibited quite good oxidase-like activity with high catalytic efficiency. Therefore, a facile and efficient colorimetric method to sensitively determine L-cysteine with a low detection limit of 33 nM (S/N = 3) has been developed. Furthermore, favorable selectivity and anti-interference ability towards the determination of L-cysteine based on this approach have also been achieved. It is believed that this colorimetric method for the detection of L-cysteine based on Co–N/C-900 will show potential applications in bioscience and bioengineering.
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PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2023
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IF 15.1
Yang Chen,Tianyi Ma,Ruiqing Ke,Mengyu Lu,Jiaxing An,Yijia Wang,Kunlun Huang,Yunbo Luo,Jin-Cheng Li,Nan Cheng
The consumption of Se-rich foods is a highly effective means of augmenting a person’s intake of Se, which plays a critical role in human health; however, excessive Se consumption can be toxic. The determination of Se levels is therefore of paramount importance to ensure the safety of both the production and consumption of selenium-rich foods. In this study, a rapid and user-friendly method is developed for the analysis of selenium-rich foods wherein the detection process is similar to watching three-dimensional movies in a theater. A portable 3D-printed colorimetric device called the Detection THEATER ( T ime-saving, H igh-sensitive, E asy, A ccurate, T elling, E conomical, and R apid) is first constructed for the rapid and visually accessible colorimetric analysis of samples in nonlaboratory settings. Subsequently, the Co-N-C nanozyme is doped with Pt to produce a Pt-Co-N-C nanozyme with superior peroxidase-like activity, which serves as the viewing glasses for signal amplification in the Detection THEATER. The Detection THEATER exhibits excellent sensitivity and accuracy, including a linear range of 0.5–1.2 μg/mL and a low detection limit of 0.026 μg/mL. The pretreatment of food samples is also optimized and simplified, thereby reducing processing times three-fold and enhancing accessibility and usability. The Pt-Co-N-C nanozyme-based Detection THEATER, demonstrated outstanding specificity and practicality, opening up a new avenue for the analysis of selenium-rich foods.
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高影响因子
CHEMICAL ENGINEERING JOURNAL
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2025
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IF 13.2
Zhen Qiu,Guanda Shen,Zefeng Ruan,Xin Zeng,Hailu Fu,Yongfu Li,Bing Yu
The removal of organic pollutants in complex aqueous environments is often hindered by the presence of natural organic matter (NOM), such as humic acid (HA), which can interfere with pollutant degradation processes. Peroxymonosulfate (PMS) activation has emerged as a promising strategy for pollutant degradation; however, its efficiency is typically compromised by NOM interference. To address this challenge, this study develops a metal–organic framework (MOF)-derived Co-N@C hollow multi-shell nanoreactor (HoMS) that effectively isolates NOMs while targeting organic pollutants. The Co-N@C HoMS, synthesized via a “hierarchical temperature control, one-step pyrolysis” strategy, demonstrated superior catalytic performance in selectively degrading carbamazepine (CBZ) in the presence of HA. Over 99% of CBZ was removed within 10 min, even with HA present. Mechanistic studies revealed that PMS activation by Co-N@C HoMS for CBZ degradation involves both radical oxidation and electron transfer pathways. The unique size-exclusion effect of the Co-N@C HoMS selectively allows small molecules (CBZ) to pass through while blocking larger ones (HA), enabling rapid and selective pollutant degradation in complex environments. This work provides a novel solution for the efficient and selective removal of multi-component pollutants in complex environmental systems.
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高影响因子
危险品化学品经营许可证（带存储）