APPLIED SURFACE SCIENCE
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2020
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IF 6.182
Jie Xu,Xiaowei Liu,Zijian Zhou,Minghou Xu
Porphyrin based MOFs have exhibited excellent photocatalytic properties in photocatalytic CO 2 reduction and metal sites in porphyrin units play an important role in the reactions. For investigating the mechanism of different photocatalytic performance of metals sites in porphyrin units, metalloporphyrin complexes with Co and Ni metal sites (Co-POR, Ni-POR) were prepared by a short term method and used for visible-light drived CO 2 photoreduction conversion with water vapor as sacrificial agent. PL spectra indicates that the fluorescence intensity of Co-POR was obviously lower than that of Ni-POR and DFT calculation indicates that CO 2 adsorption energy on Co-POR (17.92 kJmol −1 ) is higher than that on Ni-POR (16.37 kJmol −1 ). The efficient separation of charge carries and the strong CO 2 adsorption ability are main advantages of Co-POR compared with Ni-POR. As a direct result, the experimental results showed that 0.40 μ m o l g - 1 h - 1 CO was produced over Co-POR after 4 h reaction, which is about equivalent to a 1.7-fold enhancement compared to Ni-POR under the same reaction condition.
研究领域:
化学
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材料科学
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环境科学
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产品关联
DOI
高影响因子
Energy & Environmental Materials
·
2024
·
IF 13
Shuai Cao,Wenzhuo Wu,Chaozhong Liu,Leqian Song,Qun Xu,Huacheng Zhang,Yanli Zhao
The development of active water oxidation catalysts for water splitting has stimulated considerable interest. Herein, the design and building of single atom Co sites using a supramolecular tailoring strategy are reported, that is, the introduction of pillar[4]arene[1]quinone (P4A1Q) permits mononuclear Co species stereoelectronically assembled on MoS 2 matrix to construct an atomically dispersed MoS 2 @Co catalyst with modulated local electronic structure, definite chemical environment and enhanced oxygen evolution reaction performance. Theoretical calculations indicate that immsobilized single-Co sites exhibit an optimized adsorption capability of oxygen-containing intermediates, endowing the catalyst an excellent electrocatalytic oxygen evolution reaction activity, with a low overpotential of 370 mV at 10 mA cm −2 and a small Tafel slope of 90 mV dec −1 . The extendable potential of this strategy to other electrocatalysts such as MoS 2 @Ni and MoS 2 @Zn, and other applications such as the hydrogen evolution reaction was also demonstrated. This study affords new insights into the rational design of single metal atom systems with enhanced electrocatalytic performance.
研究领域:
材料科学
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电催化
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能源化学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
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IF 13.3
Shengxin Chen,Bin He,Yingwei Li,Ruirui Wang,Ping Chen,Xingang Li,Ruixia Liu
The selective oxidation of cyclohexane to cyclohexanone and cyclohexanol (KA oils) without additional initiator remains a challenge because of its inherent low activity and limited selectivity. To promote the selectivity of KA oils at high reaction conversion, a series of novel cobalt-based poly(ionic liquid)s (Co-PILs) catalysts were designed. The electronic structure and the microenvironment of Co sites in Co-PILs were regulated by tuning the contents of Co. By the regulation of the microenvironment, the cyclohexane conversion and KA oils selectivity are improved by 19% and 47% (Co-PIL-1–2.5) compared with traditional metal salt catalysts, respectively. Mechanistic studies demonstrated that the electronic structure and coordination environment of transition metals can be effectively tailored. Notably, Co-PILs with low metal loading exhibit a remarkable ability to improve the reaction by transitioning from a low-spin to a high-spin state. Moreover, by adjusting the ratio of cobalt ions to ionic liquid monomers derived from PILs, the acidity, oxygen activation, and desorption of reactive oxygen species were also regulated accordingly. These properties play a pivotal role in the oxidation process, ultimately allowing for precise control over the activity and selectivity.
研究领域:
催化化学
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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
·
2024
·
IF 13.3
Ting Zhang,Wantong Zhao,Shiyan Li,Wenguang Cui,Baojun Wang,Yuefeng Liu,Riguang Zhang,Zhongkui Zhao
Selective transfer hydrogenation coupling of nitroarenes with benzyl alcohol is one of the most reliable strategies to access functionalized imines, but challenges remain, such as the multiple and complicated operate process, low reactivity, poor selectivity results from deep hydrogenation. Constructing highly efficient catalyst is critical for this organic transformation process. Herein, we propose a unique single-atom Co-N 4 sites on N-doped carbon, with significantly upshifted d -band center, fabricated by a one-pot solid-phase carbonization strategy, which generates an excellent catalyst for one-pot selective transfer hydrogenation coupling of nitroarenes with benzyl alcohol to various functionalized imines. Experimental and theoretical investigations demonstrate the clear linear correlation among the nitrobenzene turnover number ( TON ) and d -band center over the as-prepared Co based samples, indicating the vital effect of electronic structure of Co sites on catalytic performances. Furthermore, owing to the upshifted d -band center of Co-N 4 sites, thedesorption of aniline and N -benzylideneaniline is promoted, which accelerates the spontaneous condensation coupling of aniline with benzaldehyde and inhibits the deep hydrogenation of N -benzylideneaniline. Consequently, an outstanding catalytic performance with high activity and selectivity in transfer hydrogenation coupling for imine synthesis has been realized. This work not only presents a highly efficient non-precious metal catalyst for functionalized imines production, but also illustrates the critical effect of electron structure of metallic active site on catalytic properties and opens a new avenue for fabricating diverse single-atom catalysts for selective hydrogenation reactions.
研究领域:
化学
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材料科学
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催化反应
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产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2022
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IF 6.371
Yan Wang,Guangshe Li,Chang Liu,Xinbo Li,Liping Li
Metal geometrical structure engineering of composite catalysts is powerful to boost their photocatalytic performance of hydrogen evolution . Herein, by rationally designing, transition metal phosphides (TMPs) have been loaded onto the P doped g-C 3 N 4 (PCN) to construct catalysts TMPs/PCN. For the first time, the effect of geometrical structure of TMPs on the photocatalytic activity is optimized and a geometrical-site-dependent photocatalytic hydrogen evolution is experimentally determined. Tri-metallic FeCoNiP/PCN, having 59.6% occupancy of tetrahedral cobalt sites, gives hydrogen production rate of 205 μmol/g/h, better than that of mono-metallic (FeP, CoP , NiP), bi-metallic (FeCoP, CoNiP, FeNiP) TMPs/PCN, and even much superior to that of Pt/b-g-C 3 N 4 and Pt/PCN. Trimetallic TMPs/PCN catalysts also show excellent OER performance. In addition to the efficient electron transfer between FeCoNiP and PCN, which can effectively improve the separation of photogenerated carriers, the high occupancy of tetrahedral cobalt sites of FeCoNiP as a co-catalyst promotes the formation of active intermediates, being the key to significantly improve the catalytic performance of ternary FeCoNiP/PCN. The findings in this work, especially about a link of the photocatalytic performance of TMPs/PCN composites and occupancy of tetrahedral cobalt site in co-catalysts TMPs, can open new occasion for creating novel composite catalysts and extending to other applications.
研究领域:
材料科学
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催化化学
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产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2021
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IF 19.503
Zhe Xu,Yijie Wu,Qiuyi Ji,Taozhu Li,Chenmin Xu,Chengdu Qi,Huan He,Shaogui Yang,Shiyin Li,Shicheng Yan,Cheng Sun,Limin Zhang,Zhigang Zou
Identifying the spatial effects of cobalt cations in cobalt-based heterogeneous catalysts contributes to develop effective peroxymonosulfate (PMS) activators in water treatment. Herein, we investigated typical tetrahedral and octahedral cobalt ions in CoAl 2 O 4 and ZnCo 2 O 4 via an inactive cation substitution strategy towards spinel Co 3 O 4 . ZnCo 2 O 4 (0.095 min −1 ) performs remarkably better than CoAl 2 O 4 (0.007 min −1 ) for degrading rhodamine B, while non-radical 1 O 2 is the dominant reactive oxygen species. Then, interface kinetics characterized by systemic electrochemical techniques indicate the feasibility of Co 2+ /Co 3+ transformation and charge transfer resistance at catalyst-electrolyte interface determine intrinsic activity. Octahedral cobalt species exhibit superior intrinsic activities comparing with tetrahedral ones on the removal of several dye and aromatic pollutants. Additionally, flat band potentials of cobalt-based oxides reflecting Fermi level positions is a thermodynamic factor to activate PMS. Our work attempts to further understand spatial occupation-activity relationship of cobalt sites to design efficient PMS activators.
研究领域:
环境科学
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催化化学
✓ 已验证
DOI
高影响因子
Nature Communications
·
2024
·Vol. 15
·期 1
·1-12
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IF 14.7
Lyu Wenyuan,Liu Yang,Chen Datong,Wang Fengliang,Li Yingwei
Photocatalytic conversion of CO 2 into syngas is highly appealing, yet still suffers from the undesirable product yield due to the sluggish carrier transfer and the uncontrollable affinity between catalytic sites and intermediates. Here we report the fabrication of Co sites with tunable electron localization capability on two dimensional (2D) nanosheets assembled three dimensional (3D) ordered macroporous framework (3DOM-NS). The as-prepared Co-based 3DOM-NS catalysts exhibit attractive photocatalytic performances toward CO 2 reduction, among which the cobalt sulfide one (3DOM Co-SNS) shows the highest syngas generation rate up to 347.3 μmol h −1 under the irradiation of visible light and delivers a remarkable catalytic activity (1150.7 μmol h −1 ) in a flow reaction system under natural sunlight. Mechanism studies reveal that the high electron localization of metal sites in 3DOM Co-SNS strengthens the interaction between Co and HCOO* via the orbital interactions of d yz / d xz - p and s - s , thus facilitating the cleaving process of C-O bond. Additionally, the ordered macroporous framework with nanosheet subunits elevates the transfer efficiency of photoexcited electrons, which contributes to its high activity.
研究领域:
材料科学
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环境科学
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化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Environmental Chemical Engineering
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2022
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IF 7.968
Lidong Wang,Xiuze Li,Hanxia Chen,Yifei Liang,Zhongfei Xu,Juzhe Liu,Wen Liu,Juanjuan Qi
Sulfite(S(IV))-induced advanced oxidation processes (AOPs) have great prospect in the field of removing organic pollutants , yet developing highly efficient sulfite activation systems and optimizing active sites for favorable catalytic processes are important but still challenging. Herein, we have achieved a composite catalyst with modulated Co electron structure for efficient AOPs by decorating Co(OH) 2 on ultrathin graphitic carbon nitride (g-C 3 N 4 ) nanosheet through an adjustable strategy, which exhibits high catalytic performance in S(IV) activation system. At optimal pH 9, 92% of paracetamol (APAP) (0.005 mM) is removed with the degradation rate constant of k 1 = 0.193 min −1 within 30 min in presence of the composite material. The in-situ synthesis mode introduces strong heterogeneous interface interaction, resulting in directional electron transfer from cobalt hydroxide layer to g-C 3 N 4 sheet revealed by X-ray photoelectron spectroscopy and density functional theory (DFT) calculations. The underlying activity enhanced mechanisms for APAP in S(IV) activation system using Co(OH) 2 /g-C 3 N 4 are proposed: (i) The ultrathin g-C 3 N 4 nanosheets provide more anchoring centers for generating small Co(OH) 2 nanoparticles with abundant active sites which benefit to form metastable intermediates of Co(II)-SO 3 ; (ii) The strong interface interaction induces charge redistribution between Co(OH) 2 and g-C 3 N 4 conformed by DFT calculation, which modulates the d-band center of Co site and strengthens the bind of Co(II)-SO 3 , thereby giving rise to radicals ( • OH, SO 4 • and O 2 • ) and nonradicals ( 1 O 2 and electron transfer) oxidation for highly-efficient removal APAP. Our work will pave the way to build an environmentally friendly strategy for emerging organic pollutant degradation in water through building efficient catalysts in sulfite activation system.
研究领域:
环境科学
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催化化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Cleaner Production
·
2023
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IF 11.1
Shuqiang Pang,Chengfeng Zhou,Yuanyuan Sun,Kewei Zhang,Wanneng Ye,Xiaoliang Zhao,Liping Cai,Bin Hui
Structural design of high-performing catalysts for boosting refractory organic pollutants degradation remains a great challenge. Herein, a natural wood-derived catalyst comprising of wood carbon and Fe/Co sites was proposed as the peroxymonosulfate (PMS) activator to enhance ciprofloxacin (CIP) pollutant degradation. The bimetallic Fe/Co sites were highly dispersed and stabilized on carbon surface. The carbon-based catalyst achieved 100% removal rate for CIP within 4 min. After four consecutive cycles, the removal rate still reached 92.8%, displaying separable and reusable ability of this catalyst. The carbon-based catalyst could also exhibit excellent degradation performance under a wide pH range of 2.0–8.0. Density functional theory (DFT) calculation revealed that Fe/Co sites at wood carbon had the high adsorption energy and induced interfacial electron transfer for enhanced breakage of O–O bond. The sulfate radical (SO 4 •− ), hydroxyl radical (•OH) and singlet oxygen ( 1 O 2 ) were main reactive oxygen species and their relative contribution was calculated to be 13.51%, 17.54% and 68.95%, respectively. The formed by-products and intermediates had almost no toxicity. This work proposes a new structural design of wood carbon-based system for enhancing antibiotic pollutant in aqueous environment, which facilitates the development of wastewater treatment technology.
研究领域:
环境科学
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催化材料
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废水处理
✓ 已验证
产品关联
DOI
高影响因子
Frontiers in Materials
·
2022
·
IF 3.985
Yang Jiangping,Zhang Zhe,Sun Siyuan,Wang Cheng
The development of transition metal oxides (TMOs) as electrocatalysts for oxygen evolution reaction (OER) has the potential to surpass the performance of noble-metal-based catalysts. In this work, a quenching rapidly strategy was used to synthesize Mo-modified Co3O4 nanosheet arrays as advanced catalysts. The resulting Mo-Co3O4 electrodes showed superior activity and reaction kinetics, with an overpotential of only 341 mV to drive a current density of 100 mA cm−2 and a Tafel slope of 69.0 mV dec−1. This improved performance is thought to be due to the formation of high-valence Co sites, which creates a synergistic effect. The ability to regulate the synthesis without causing obvious agglomeration and nucleation growth during annealing makes this method a promising approach for the design of other advanced functional materials.
研究领域:
材料科学
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电化学
·
纳米技术
✓ 已验证
DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2025
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IF 19
Yipu Xu,Wenru Zhao,Rui Chen,He Li,Xinyu Liu,Peiran Wu,Hui Yu,Jiansong Wang,Liu-Liu Shen,Gui-Rong Zhang,Donghai Mei
Zeolitic imidazolate frameworks (ZIFs) are widely explored as precursors for constructing electrocatalysts for the oxygen reduction reaction (ORR). However, most studies convert these frameworks into metal-nitrogen-carbon (M-N-C) catalysts via pyrolysis, a process that often compromises their structure integrity and coordination precision. Herein, it is demonstrated that ZIF-67 can serve directly as a highly-active molecular catalyst for ORR. By applying ball-milling to enhance cobalt sites exposure, the optimized ZIF-67 exhibits exceptional ORR activity in alkaline media. Combined spectroscopic and theoretical analyses reveal that this remarkable activity stems from coordinatively unsaturated Co-N 4-x sites, which transform into Co-N 4-x (OH) moieties under reaction conditions, thereby facilitating oxygen adsorption and activation. Furthermore, mild thermal treatment (≤500 °C) enhances the proportion of Co-N 4-x sites up to 48%, as confirmed by X-ray absorption spectroscopy, achieving ORR activity rivals or even exceeds conventional pyrolyzed M-N-C catalysts. This study unlocks the potential of ZIFs as active molecular electrocatalysts upon mild thermal treatment, providing a scalable and efficient strategy for optimizing ZIFs for catalytic applications while preserving their structural precision.
研究领域:
材料科学
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电化学
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催化
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纳米技术
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无机化学
✓ 已验证
产品关联
DOI
高影响因子
Nature Communications
·
2021
·Vol. 12
·期 1
·1-10
·
IF 14.919
Min Yuan,Zhou Xiao,Chen Jie-Jie,Chen Wenxing,Zhou Fangyao,Wang Zhiyuan,Yang Jia,Xiong Can,Wang Ying,Li Fengting,Yu Han-Qing,Wu Yuen
The construction of enzyme-inspired artificial catalysts with enzyme-like active sites and microenvironment remains a great challenge. Herein, we report a single-atomic-site Co catalyst supported by carbon doped boron nitride (BCN) with locally polarized B–N bonds (Co SAs/BCN) to simulate the reductive dehalogenases. Density functional theory analysis suggests that the BCN supports, featured with ionic characteristics, provide additional electric field effect compared with graphitic carbon or N-doped carbon (CN), which could facilitate the adsorption of polarized organochlorides. Consistent with the theoretical results, the Co SAs/BCN catalyst delivers a high activity with nearly complete dechlorination (~98%) at a potential of −0.9 V versus Ag/AgCl for chloramphenicol (CAP), showing that the rate constant ( k ) contributed by unit mass of metal ( k /ratio) is 4 and 19 times more active than those of the Co SAs/CN and state-of-the-art Pd/C catalyst, respectively. We show that Co single atoms coupled with BCN host exhibit high stability and selectivity in CAP dechlorination and suppress the competing hydrogen evolution reaction, endowing the Co SAs/BCN as a candidate for sustainable conversion of organic chloride.
研究领域:
催化
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材料科学
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环境化学
·
理论化学
✓ 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）