ELECTROCHIMICA ACTA
·
2018
·
IF 5.116
Anni Li,Congwei Wang,Huinian Zhang,Zheng Zhao,Jie Wang,Miao Cheng,Huifang Zhao,Junying Wang,Minghong Wu,Junzhong Wang
Electrochemical water splitting by a robust electrocatalyst plays a key role in hydrogen production for clean and sustainable energy. In this work, a kind of nanohybrid of graphene supported atomic Co and nanocrystalline Co 3 O 4 was synthesized through electrochemical synthesis of atomic cobalt onto graphene using 1-Butyl-3-methylimidzolium tetrachlorocobalt [(BMIm) 2 CoCl 4 ] as an electrolyte. By virtue of the synergistic effect of single-cobalt atoms and Co 3 O 4 nanoparticles , the nanohybrid presents enhanced electrocatalytic performance toward the oxygen evolution reaction. The low onset potential is 0.49 V (vs. Ag/AgCl) and the overpotential of the current density of 10 mA cm −2 is 0.30 V in aqueous solution, which is comparable to commercial RuO 2 . Moreover, the nanohybrid exhibits remarkably long stability for over 45 h at a fixed potential of 0.6 V.
研究领域:
材料科学
·
能源科学
✓ 已验证
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2022
·
IF 9.224
Xuanbei Peng,Hongfang Cai,Yanliang Zhou,Jun Ni,Xiuyun Wang,Bingyu Lin,Jianxin Lin,Lirong Zheng,Chak-tong Au,Lilong Jiang
Theoretical studies have demonstrated that metal atomic clusters are highly efficient in catalytic ammonia synthesis under mild conditions. However, activation of N2 over atomic clusters from an experimental viewpoint has not been systematically investigated. Here, for the first time, cobalt atomic dimers on a nitrogen–carbon support were synthesized for NH3 synthesis. It is disclosed that N2 activation over Co2 atomic clusters (Co2 ACCs) is entirely different from that over Co single-atom catalysts (Co SACs) or Co nanoparticles (Co NPs). A suite of in situ spectroscopy studies reveal that Co2 ACCs not only provide active sites to promote strong metal–support interactions but also initiate strong interclustering interactions, resulting in electron transfers from Co d-orbitals to antibonding orbitals of N2 molecules. As such, the activation energy of the Co2 ACC catalyst in NH3 synthesis is small. Consequently, the catalytic activity of the developed Ba-promoted Co2 ACC catalyst reached 19.42 mmolNH3 gcat–1 h–1 at 400 °C and 1 MPa, which is much superior than that of other Co-based catalysts under such mild conditions. More importantly, the synthesis strategy of Co2 ACCs has general applicability as demonstrated in the preparation of Fe2 and Mn2 atomic clusters.
研究领域:
催化化学
·
材料科学
·
物理化学
✓ 已验证
DOI
高影响因子
ACS Applied Nano Materials
·
2024
·
IF 5.3
Mingdong Xu,Yongling Yu,Guojun Shi,Panming Jian,Xu Hou,Enxian Yuan
Although single metal sites on graphitic carbon nitride (g-C3N4) are extensively employed in the catalysis field, the related study is based on the flat g-C3N4 surface model, which is far beyond the reality of the curved structure involved in g-C3N4. Herein, g-C3N4 nanorods with diameters of 9.0 and 7.0 nm are synthesized via the hard template approach to support single-atom Co for the catalytic oxidation of cyclohexane. Comprehensive characterizations, combined with theoretical calculations, find that the curved structure would broaden the space of g-C3N4 interlayers, modulate the electronic structure, and reduce the coordination number of atomic Co. The mechanism study reveals that compared with Co atoms on a flat g-C3N4 surface, the low-coordinated Co atoms anchored on a curved g-C3N4 surface are capable of enhancing the reactant adsorption and facilitating the oxygen dissociation, thereby boosting the catalytic cyclohexane oxidation. The cyclohexane conversion on resultant Co/g-C3N4-9 nm reaches up to 22.4% at the overall selectivity of above 95% under mild reaction conditions, outperforming state-of-the-art nonprecious metal-based catalysts. The present work not only offers a synthesis strategy of the effective single-atom metal catalysts for the cyclohexane oxidation but also sheds light on the origin of the enhanced catalytic performance of curved g-C3N4-based catalysts.
研究领域:
催化化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
DALTON TRANSACTIONS
·
2023
·Vol. 52
·期 28
·9780-9786
·
IF 4
Yanfang Li,Jiali Zhang,Puyi Lei,Shouwu Guo
In this work, we disperse Co atomically on three-dimensional networks of N-doped graphene (3DNG) through the impregnation of 3DNG with Co(Ac)2·4H2O solution followed by rapid pyrolysis. The structure, morphology and composition of the as-prepared composite, namely ACo/3DNG, are characterized. The atomically dispersed Co and enriched Co–N species afford the ACo/3DNG with unique catalytic activity for hydrolysis of organophosphorus agents (OPs), and the network structure and super-hydrophobic surface of 3DNG ensures excellent physical adsorption capacity. Thus, ACo/3DNG demonstrates good capability for removal of OPs pesticides from water.
研究领域:
环境科学
·
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Yong-Rong Sun,Xue Zhang,Li-Guang Wang,Zhi-Kai Liu,Ning Kang,Ni Zhou,Wen-Long You,Jia Li,Xue-Feng Yu
Tailoring the charge density of active metal center is one effective approach to improve the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) performance by accelerating the rate-determining step. Herein, we propose a novel strategy, that is, lattice contraction tailoring to modulate the charge density of active Co atom in LaCoO 3 by doping Ce ions into the host lattice. The introduction of Ce can boost the bifunctional oxygen electrode activity (0.81 V) with better durability, surpassing the pure LaCoO 3 (1.00 V) catalyst. Due to the improved catalysis performance, the Zn-air battery based on lattice constrain tailoring strategy has demonstrated the 1.2- and 2.0-fold enhancement for current and power densities, respectively. The theoretical calculation reveals that the lattice contraction tailoring in LaCoO 3 can effectively increase the electrical conductivity, decrease the reaction free energy and enhance the rate-determining step rate, which causes the accelerated ORR and OER rates. This study provides a novel insight into designing high-performance oxygen electrocatalyst through engineering the crystal parameters of catalysts.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2025
·
IF 21.1
Deqiang Kong,Yueshuai Wang,Yong Yan,Zongge Li,Yue Lu,Ge Chen
Advancing the two-electron (2e - ) oxygen reduction reaction (ORR) in acidic media is pivotal for sustainable, on-demand hydrogen peroxide (H 2 O 2 ) production, but remains challenged by insufficient activity/selectivity at industrially relevant high current densities. We present a breakthrough catalyst design featuring cobalt atomic sites embedded in curved nitrogen-doped carbon layers (c-Co-N-C). This architecture achieves nearly 90 % H 2 O 2 selectivity across a wide potential window, delivering 11.70 mol g⁻¹ h⁻¹ productivity at 300 mA cm −2 with 80 % Faraday efficiency in flow cell tests. Particularly, the catalyst maintains a stable 300 mA cm −2 operation under 1.9 V cell voltage (surpassing prior-art systems by 0.2 V) for 120 h in a PEM electrolyzer, producing pure-phase H 2 O 2 (4.1 wt%). Through integrated experimental and computational analysis, we reveal two complementary enhancement mechanisms: first, the finite element simulations quantify the enhanced interfacial electric field that concentrates protons and dissolved oxygen; then, the density functional theory (DFT) calculations indicate a downshift in Co d -band center optimizes *OOH adsorption while suppressing O-O bond cleavage. This work establishes curvature engineering as a universal design strategy for advanced catalysts through controlled structural modification, opening new pathways for sustainable chemical synthesis.
研究领域:
材料科学
·
催化化学
·
可再生能源
✓ 已验证
产品关联
DOI
高影响因子
Nano Energy
·
2020
·
IF 16.602
Wengang Liu,Wenjuan Hu,Lijun Yang,Jian Liu
By analogy to mono-nuclear metalloenzymes , single-atom dispersed catalysts (SACs) demonstrate very promising performance for many conventional heterogeneous and homogeneous reactions. However, the prospect of integrating SACs with enzymatic catalysis is still unexplored. Herein, atomically dispersed Co sites on ultrathin two-dimensional (2D) carbon nitride nanosheets (Co 1 /C 3 N 4 ) were constructed and applied for efficiently photochemical cofactor (NADH) regeneration. The NADH regeneration yield reached as high as 99%. Subsequently, the in-situ regenerated-NADH triggered alcohol dehydrogenase for enzymatic reduction of aldehyde where 100% alcohol yield was achieved. Using atomic spectroscopy characterization and theoretical calculation, the genuine active sites of Co 1 /C 3 N 4 catalyst in reaction system were revealed in the form of CoN 3 - Cp* moieties ( Cp* , 1,2,3,4,5-pentamethylcyclopentadiene). Such a well-defined atomic catalyst opens a new avenue for the organic transformation application of single-atom catalysts in enzyme catalysis.
研究领域:
催化
·
材料科学
·
酶工程
·
光化学
✓ 已验证
产品关联
DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2025
·
IF 19
Xinyu Wang,Sichen Huo,Yanjie Chen,Mingyi Wang,Ying Dai,Jinlong Zou
Cobalt atom cluster (Co AC )-based electrocatalysts usually exhibit high activity for oxygen reduction reaction (ORR), but display limited performance in oxygen evolution reaction (OER). To enhance their bifunctional catalytic efficiency, it is crucial to tailor the d -orbital electronic structure of Co AC through orbital coupling effect, optimizing the chemisorption of O-intermediates. Herein, a 3 d -4 d orbital coupling strategy is used to construct a Co AC -molybdenum carbide/nanocarbon cake (Co AC -Mo x C/CC) catalyst with a hollow structure for ORR/OER in zinc-air batteries (ZABs). Experimental and theoretical results confirm that the 4 d transition metal Mo, with fewer d electrons and more unfilled orbitals, interacts strongly with Co sites through d - d coupling, promoting electron enrichment and triggering 3 d -orbital electron delocalization. This process accelerates the rate-limiting steps of *OH desorption for ORR and *OOH formation for OER, leading to an ultra-low potential gap of 0.604 V and improved stability. Notably, the Co AC -Mo x C/CC-based liquid and flexible all-solid-state ZABs exhibit excellent performance with high open-circuit voltages of 1.49 and 1.47 V, and power densities of 146.4 and 103.4 mW cm −2 , respectively, highlighting their potential to replace precious metal catalysts. This study may open new avenues for manipulating the electronic properties of Co AC -based electrocatalysts and boosting activity through the d - d orbital coupling strategy.
研究领域:
材料科学
·
电化学
·
催化科学
✓ 已验证
产品关联
DOI
高影响因子
Nature Communications
·
2020
·Vol. 11
·期 1
·1-10
·
IF 12.121
Wang Xiuyun,Peng Xuanbei,Chen Wei,Liu Guangyong,Zheng Anmin,Zheng Lirong,Ni Jun,Au Chak-tong,Jiang Lilong
The industrial synthesis of ammonia (NH 3 ) using iron-based Haber-Bosch catalyst requires harsh reaction conditions. Developing advanced catalysts that perform well at mild conditions (<400 °C, <2 MPa) for industrial application is a long-term goal. Here we report a Co-N-C catalyst with high NH 3 synthesis rate that simultaneously exhibits dynamic and steady-state active sites. Our studies demonstrate that the atomically dispersed cobalt weakly coordinated with pyridine N reacts with surface H 2 to produce NH 3 via a chemical looping pathway. Pyrrolic N serves as an anchor to stabilize the single cobalt atom in the form of Co 1 -N 3.5 that facilitates N 2 adsorption and step-by-step hydrogenation of N 2 to *HNNH, *NH-NH 3 and *NH 2 -NH 4 . Finally, NH 3 is facilely generated via the breaking of the *NH 2 -NH 4 bond. With the co-existence of dynamic and steady-state single atom active sites, the Co-N-C catalyst circumvents the bottleneck of N 2 dissociation, making the synthesis of NH 3 at mild conditions possible.
研究领域:
催化
·
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Nature Communications
·
2023
·Vol. 14
·期 1
·1-10
·
IF 16.6
Ren Xinyi,Zhao Jian,Li Xuning,Shao Junming,Pan Binbin,Salamé Aude,Boutin Etienne,Groizard Thomas,Wang Shifu,Ding Jie,Zhang Xiong,Huang Wen-Yang,Zeng Wen-Jing,Liu Chengyu,Li Yanguang,Hung Sung-Fu,Huang Yanqiang,Robert Marc,Liu Bin
While exploring the process of CO/CO 2 electroreduction (CO x RR) is of great significance to achieve carbon recycling, deciphering reaction mechanisms so as to further design catalytic systems able to overcome sluggish kinetics remains challenging. In this work, a model single-Co-atom catalyst with well-defined coordination structure is developed and employed as a platform to unravel the underlying reaction mechanism of CO x RR. The as-prepared single-Co-atom catalyst exhibits a maximum methanol Faradaic efficiency as high as 65% at 30 mA/cm 2 in a membrane electrode assembly electrolyzer, while on the contrary, the reduction pathway of CO 2 to methanol is strongly decreased in CO 2 RR. In-situ X-ray absorption and Fourier-transform infrared spectroscopies point to a different adsorption configuration of *CO intermediate in CORR as compared to that in CO 2 RR, with a weaker stretching vibration of the C–O bond in the former case. Theoretical calculations further evidence the low energy barrier for the formation of a H-CoPc-CO – species, which is a critical factor in promoting the electrochemical reduction of CO to methanol.
研究领域:
电化学
·
催化
·
光谱学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）