Catalysis Science & Technology
·
2023
·Vol. 13
·期 6
·1748-1754
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IF 5
Shaoyuan Guo,Xinli Tong,Lingwu Meng,Guobao Yang
Selective oxidative C–C and C–O bond cleavage is of significance to the efficient utilization of biomass and biomass-derived platform compounds. In this work, the selective oxidative cleavage of C–C and C–O bonds has been developed with an iron-based catalyst (Fe–N–C) in the presence of molecular oxygen. Specifically, the β-O-4 lignin model compound was successfully converted to phenol and methyl benzoate in a methanol solvent, where the substrate conversion was 95.0% and the yields of phenol and methyl benzoate were 94.9% and 63.7%, respectively, when the reaction was performed with the Fe–N–C-850 catalyst at 120 °C for 4 h. Also, the oxidative transformations of other lignin models to phenols and methyl benzoates were achieved. Further investigations showed that the existence of the Fe3C phase in the catalyst plays an important role in the aerobic oxidative cleavage of C–C and C–O bonds in the β-O-4 lignin model.
研究领域:
生物质化学
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催化化学
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产品关联
DOI
高影响因子
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
·
2020
·Vol. 22
·期 20
·11508-11518
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IF 3.43
Jing Chen,Hanling Yang,Hongquan Fu,Hongyan He,Qiang Zeng,Xuehui Li
Electrochemical oxidation is a promising and effective method for lignin depolymerization owing to its selective oxidation capacity and environmental friendliness. Herein, the electrooxidation of non-phenolic alkyl aryl ether monomers and β-O-4 dimers was experimentally (by cyclic voltammetry, in situ spectroelectrochemistry, and gas chromatography-mass spectroscopy) and theoretically (by DFT calculations) explored in detail. Compared to the reported literature (T. Shiraishi, T. Takano, H. Kamitakahara and F. Nakatsubo, Holzforschung, 2012, 66(3), 303–309), 1-(4-ethoxyphenyl)ethanol showed a distinguishable oxidation pathway, where the resulting carbonyl product surprisingly underwent a bond cleavage on alkyl–aryl ether to ultimately produce a quinoid like compound. In contrast, β-O-4 dimers, like 2-phenoxy-1-phenethanol and 2-phenoxyacetophenone also demonstrated electrochemical oxidation induced by Cβ–O and Cα–Cβ bond cleavages. For the oxidation products, the presence of the Cα-hydroxyl group in dimers was the key to selectively generate aldehyde-containing species under mild electrochemical conditions, otherwise it produces alcohol-containing products following a different mechanism compared to the CαO containing dimers.
研究领域:
林产化学
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环境科学
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有机化学
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DOI
PubMed
高影响因子
ACS Catalysis
·
2021
·
IF 13.084
Yuebing Xu,Wenda Yu,Hao Zhang,Jian Xin,Xiaohui He,Bing Liu,Feng Jiang,Xiaohao Liu
Various Co-based SAPO-34 catalysts were prepared using different methods, including ion exchange (IE), incipient-wetness impregnation (IWI), and solid-phase grinding (SPG), to correlate the chemical states of Co species with the C–H and C–C bond scissions in ethane dehydrogenation. The IE-prepared Co/SAPO-34 led to stable, unreducible, and isolated exchanged Co sites anchored on the zeolite framework with a structure of −AlF–O–Co–O– and showed the highest selectivity to ethylene of close to 98% at 600 °C, which suggests that these Co sites favors suppressing the C–C bond scission in ethane. In comparison, the IWI- and SPG-prepared Co/SAPO-34 catalysts, especially for those with a high Co loading, inevitably give Co oxide clusters that are easily reduced into metallic Co. Together with catalytic results, characterizations, and DFT calculations, it is confirmed that the reduced Co clusters, especially for those outside SAPO-34 channels without the confinement effect, favor both C–H and C–C bond scission, boosting the conversion of ethane into CH4 or/and coke; however, the ionic-state −Co–O– species can smoothly terminate the ethane dehydrogenation for the ethylene product due to relatively high energy barriers for both C–H and C–C bond scission, avoiding a deep dehydrogenation and C–C cracking. As expected, the unreducible −Co–O– sites are very stable in the title reaction without deanchoring from the zeolite framework in a 100 h cyclic test. This study not only demonstrates the stable −Mδ+–Oδ− structure favorable for suppressing C–C bond scission but also highlights a catalyst-constructing strategy for Co-based and similar metal-based catalysts for dehydrogenation of other light alkanes.
研究领域:
催化化学
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材料科学
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计算化学
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Su Wang,Qifang Sun,Chen Li,Dongge Wang,Yue Ma,Hongzhou Zhang,Xixi Shi,Lianqi Zhang,Dawei Song
Given the high combustion or explosion potential of liquid electrolyte, polymer electrolytes have attracted intensive attention due to high safety, compatible interface and flexible processability. However, the related low ionic mobility remains an issue for related wide application. Herein, a crosslinked polymer electrolyte (abbreviated as PMEP) comprising abundant oxygen-contained groups (C-O-C/C=O) is developed. With the crosslinking agent of ethoxylated trimethylolpropane triacrylate (ETPTA), a high transference number ( t Li + =0.69) is obtained since C-O/C=O are conducive to the transfer of Li ions. Specifically, C=O group exists in individual monomers in order to be applicable to high voltage cathode, therefore, a criss-cross network containing abundant sites conducive to ion transport is constructed and rapid ion transfer as well as enhanced mechanical strength can be realized even in high potential system. With the coordination effect of C-O and C=O, PMEP exhibits rapid Li ion transfer and a wide electrochemical stability window of 5.1 V. As for Li//Li symmetrical cell, a stable voltage profile with slight polarization of 60 mV is displayed for over 550 h at 1 mA cm −2 . After assembled with LiNi 0.8 Co 0.15 Al 0.05 O 2 cathode, a high discharge specific capacity of 190.6 mAh g −1 is delivered and the capacity retention reaches 86 % at 0.1C for 100 cycles. This work provides a promising method for designing high-performance polymer electrolytes for lithium metal batteries.
研究领域:
材料科学
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电化学
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能源存储
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产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2022
·
IF 24.319
Zhizhou Cai,Ning Cao,Fanxing Zhang,Xiangzhou Lv,Ke Wang,Yi He,Yao Shi,Hao Bin Wu,Pengfei Xie
Electrocatalytic CO 2 reduction into ethanol driven by renewable energy represents a promising strategy for energy storage and mitigation of global warming, but it has remained challenging to gain high activity and selectivity of ethanol. Here we take advantage of atomic arrangement in immiscible Ag-Cu composite during annealing and establish hierarchical interfaces in the obtained core-shell catalyst. The atomic Ag-Cu interactions increase electrochemical surface area and expedite charge dynamics, resulting in an unprecedented electrocatalytic performance with the faradaic efficiency of C 2+ products, ethanol as 80.2 %, 52.6 % and the current density of ∼320 mA cm −2 at −1.0 V (versus reversible hydrogen electrode). Moreover, the Ag-Cu catalyst exhibits a notable stability for ∼60 h. Mechanism studies reveal that local CO intermediates preferentially accumulate on the core, then migrate to the continuous Cu surface for C-C coupling energy-favorably toward ethanol. Our work highlights a novel design principle as interface engineering for advanced tandem electrocatalysts.
研究领域:
材料科学
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电化学
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能源存储与转换
✓ 已验证
产品关联
DOI
高影响因子
ACS Catalysis
·
2019
·
IF 12.221
Huifang Liu,Hongji Li,Nengchao Luo,Feng Wang
Lignin is the largest carrier of aromatics on earth, and its depolymerization can afford value-added aromatic products. Direct cleavage of the C–C bonds in lignin linkages is significant, but it is challenging to obtain low-molecular-weight aromatic monomers. Herein, using vanadium catalysts under visible light, we selectively cleave the C–C bonds in β-1 and β-O-4 interlinkages occluded in lignin models and extracts by an oxidative protocol. Visible light irradiation triggered single electron transfer between the substrate and the catalyst, which further induced the selective Cα–Cβ bond cleavage and generated the final aromatic products through radical intermediates. Using this photocatalytic chemistry, the reactivity of lignin models and the selectivity of Cα–Cβ bond cleavage were significantly improved. More importantly, this protocol affords aromatic monomers through the fragmentation of organosolv lignins even at room temperature, indicating the potential of photocatalytic C–C bond cleavage of lignin linkages under ambient conditions.
研究领域:
化学
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环境科学
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产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2023
·
IF 9.9
Yufeng Wang,Qing Ye,Lu Lin,Yanxia Zhao,Yongliang Cheng
Designing and fabricating highly competent and inexpensive electrocatalysts are highly desirable for application in electrocatalytic water splitting. In this study, we synthesized NiFeRu/C nanofibers and Ru, Fe dual-doped Ni 5 P 4 (Ru, Fe-Ni 5 P 4 )/C nanofibers as complementary electrocatalysts for overall water splitting through electrospinning, carbonization, and phosphorization treatment, respectively. The NiFeRu/C nanofibers and Ru, Fe-Ni 5 P 4 /C nanofibers showed high hydrogen evolution reaction and oxygen evolution reaction activity, respectively, due to the presence of numerous exposed active sites and optimized adsorption capacity for the reaction intermediates contributed by the synergistic interaction among different metal components in the electrocatalysts. Hence, the assembled asymmetrical electrolytic cell effectively promoted overall water splitting, requiring a voltage of 1.569, 1.744, and 1.872 V to achieve a current density of 100, 500, and 1,000 mA cm −2 , respectively, and it was better than Pt/C||IrO 2 . Additionally, the electrolytic cell could work at 500 mA cm −2 for 100 h without any noticeable deterioration in activity, which indicated that it was durable at high current density. In this study, we described a novel method for designing highly efficient electrocatalysts for overall water splitting.
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Pei-dong Wu,Lanyun Li,Hu Li,Zhen Fang
Sustainable upgrading of biomass to high-value chemicals is greatly dependent on catalytic C-C/C-O bond cleavage of high selectivity. Here, an oxidation-enhanced photoelectrochemical protocol was developed to be capable of breaking different types of C-C bonds for efficiently producing aromatic carboxylic acids (85.0–99.8% yields) from lignin. Ni local electronic state of the prepared F-Fe 2 O 3 -Co:NiO x H y with excellent durability could be modulated, and high-valence Ni(Ⅳ) reactive species played a key role in the oxidative C-C bond scission of various lignin models. In-situ characterization and control experiments indicated that photocatalytic radical and electrocatalytic interface facilitated C-H/O-H delocalization, contributing significantly to the enhanced oxidation process. In addition, quantum calculations elaborated that photo-excited holes and Ni(Ⅳ) are key reactive species for enhancive electrocatalytic cleavage of different C-C bonds in lignin to exclusively furnish aromatic carboxylic acids. This research provides a renewable funnel strategy for using solar energy to produce high-value mono-functional products from biomass.
研究领域:
化学
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可再生能源
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催化科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
·
2023
·
IF 5.7
Yuzhu Shen,Wei Sun,Yonglong Xu,Qingbo Wen,Hongbo Zhang,Xiang Xiong
In this study, to overcome the difficulties associated with the preparation of PyC-ceramic interface and controllable deposition of the structure, we initially used a two-step molten salt infiltration method to prepare a C/C-Me-Zr-Hf (Me = Ta, Si) composite with excellent oxyacetylene ablation performance. The microstructure and the behavior of ablative were addressed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) as well as by X-ray diffraction（XRD）. The results reveals that C/C-ZrHfC-SiC composite prepared by two-step molten salt infiltration method have a controllable ultra-high temperature ceramic structure and better ablation resistance.
研究领域:
材料科学
·
航空航天工程
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DOI
高影响因子
Nature Communications
·
2024
·Vol. 15
·期 1
·1-11
·
IF 14.7
Yang Ruixin,Cai Yanming,Qi Yongbing,Tang Zhuodong,Zhu Jun-Jie,Li Jinxiang,Zhu Wenlei,Chen Zixuan
C–C coupling is of utmost importance in the electrocatalytic reduction of CO 2 , as it governs the selectivity of diverse product formation. Nevertheless, the difficulties to directly observe C–C coupling pathways at a specific nanocavity hinder the advances in catalysts and electrolyzer design for efficient high-value hydrocarbon production. Here we develop a nano-confined Raman technology to elucidate the influence of the local electric field on the evolution of C–C coupling intermediates. Through precise adjustments to the Debye length in nanocavities of a copper catalyst, the overlapping of electrical double layers drives a transition in the C–C coupling pathway at a specific nanocavity from *CHO–*CO coupling to the direct dimerization of *CO species. Experimental evidence and simulations validate that a reduced potential drop across the compact layer promotes a higher yield of CO and promotes the direct dimerization of *CO species. Our findings provide insights for the development of highly selective catalyst materials tailored to promote specific products.
研究领域:
催化化学
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电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2025
·
IF 19
Wen Zhang,Yingxiu Zhao,Jiayi Li,Yu Miao,Pengkai He,Zexing Wu,Yang Zhang,Guang-Rui Xu,Lei Wang
The capacity of C‒C bond cleavage determines the pathway selectivity during the ethanol oxidation process. Herein, ultra-thin monodisperse PdCo nanosheets with an average diameter of 33 nm are successfully synthesized and the interface of Pd-O-Co is further constructed due to the introduction of lattice oxygen. Due to their ultra-thin nanosheet structure, unique surface electronic structures driven by lattice oxygen, and alloying effect, the prepared PdCo/Pd-O-Co nanosheets (PdCo/Pd-O-Co NSs) show excellent ethanol oxidation reaction (EOR) activity and stability. The mass activity and specific activity of PdCo/Pd-O-Co NSs are 12.43 A mg −1 and 22.01 mA cm −2 for EOR, which exceeded PdCo nanosheets, Pd nanosheets and commercial Pd black. In situ FTIR spectroscopy and theoretical calculation identified that lattice oxygen introduced after square-wave potential treatment can promote the cleavage of the C‒C bond. Through the introduction of lattice oxygen combined with lattice strain engineering, the PdCo/Pd-O-Co NSs surface is optimized to promote the generation of strong p-d orbital hybridization, which led to the upward shift of the d-band center and the electron delocalization effect, effectively promoting the C‒C bond cleavage and improving the anti-poisoning ability.
研究领域:
材料科学
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催化化学
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电化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
·
2023
·
IF 5.7
Zhenxiao Tang,Maozhong Yi,Zhe Zhou,Huang Wu,Yuanming Zhou,Ke Peng
A C/C-TaB 2 -SiC composite was successfully prepared by high-solid-loading slurry impregnation combined with polymer infiltration and pyrolysis. The composite had a density of 3.46 g/cm 3 and consisted of pyrolyzed carbon, carbon fibers, TaB 2 particles, and precursor-derived SiC with their mass fractions of 7.8 %, 13.0 %, 58.6 %, and 20.6 %, respectively. The C/C-TaB 2 -SiC composite possessed a flexural strength of 248.2 ± 16.8 MPa and a fracture toughness of 13.7 ± 1.6 MPa·m 1/2 , and demonstrated a non-brittle fracture behavior . After exposure to oxyacetylene flame with a heat flux of 4.18 MW/m 2 for 120 s, the ablation temperature of the sample surface reached a maximum of 2263 °C, and the mass and line ablation rates were 2.24 mg/s and 12.92 µm/s, respectively. The ablation resistance mainly comes from the hindrance of oxygen diffusion by the oxide layer composed of tantalum oxide and a small amount of SiO 2 .
研究领域:
材料科学
·
航空航天工程
✓ 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）