MOLECULES
·
2024
·Vol. 29
·期 12
·2861
·
IF 4.2
Yonghui Sun,Qiyu He,Xucheng Lv,Naizhen Zhang,Wei Yan,Jianghui Sun,Lili Zhuang
Regioselective benzanilide bromination that generates either regioisomer from the same starting material is desirable. Herein, we develop switchable site-selective C(sp2)-H bromination by promoter regulation. This protocol leads to regiodivergent brominated benzanilide starting from the single substrate via selection of promoters. The protocol demonstrates excellent regioselectivity and good tolerance of functional groups with high yields. The utility effectiveness of this method has been well exemplified in the late-stage modification of biologically important molecules.
研究领域:
有机化学
·
药物化学
✓ 已验证
DOI
PubMed
高影响因子
JACS Au
·
2024
·
IF 8.5
Xixi Liu,Liang Huang,Yurong He,Peng Zhou,Xuedan Song,Zehui Zhang
It remains challenging to construct C═N bonds due to their facile hydrogenation. Herein, a single Co atom catalyst was discovered to be active for the selective construction of C═N bonds toward the synthesis of imines and N-heterocycles via reductive coupling of nitroarenes with various alcohols, including inert aliphatic ones. DFT calculations and experimental data revealed that the transfer hydrogenation proceeded via the intramolecular hydride transfer and the transfer of H from the α-Csp3-H bond to the nitro group was the rate-determining step. The single Co atoms served as a bridge to transfer the electrons from the catalyst to the adsorbed alcohol molecules, resulting in the activation of the α-Csp3-H bond. Unlike metal nanoparticles, the C═N bonds in imine products can be reserved due to the large steric hindrance from substituents on C and N. DFT calculation also confirmed that transfer hydrogenation of the C═N bonds in imines is thermodynamically unfavored with a much higher energy barrier compared with the transfer hydrogenation of the –NO2 group (1.47 vs 1.15 eV).
研究领域:
化学
·
催化反应
·
理论计算
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF CHEMICAL TECHNOLOGY AND BIOTECHNOLOGY
·
2020
·Vol. 96
·期 3
·639-649
·
IF 2.75
Shanshan Jiang,Jin Huang,Yue Wang,Shiyu Lu,Pei Li,Cuiqin Li,Feng Li
Abstact BACKGROUND Fe based metal organic frameworks (Fe-MOFs) were prepared by solvothermal method, and carbon loaded Fe 3 O 4 (Fe 3 O 4 /C) was prepared by pyrolytic carbonization and carbothermal reduction. RESULTS Various analytical techniques were used to characterize the physicochemical structure of Fe-MOFs and Fe 3 O 4 /C under different solvothermal and calcination conditions. Fe 3 O 4 /C was then employed as a catalyst for the catalytic transfer hydrogenation of furfural with alcohol as a hydrogen donor, and the effect of hydrogen donor species, reaction temperature, and reaction time were investigated. CONCLUSION The Fe 3 O 4 /C catalyst could be easily collected with a magnet and reused for four runs without significant loss of its catalytic. A possible mechanism for the catalytic transfer hydrogenation of furfural over Fe 3 O 4 /C was proposed. © 2020 Society of Chemical Industry (SCI)
研究领域:
化学工程
·
材料科学
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2024
·
IF 8.3
Liming Guo,Xin Wan,Jieyuan Liu,Xu Guo,Xiaofang Liu,Jiaxiang Shang,Ronghai Yu,Jianglan Shui
Synergistic effects have been applied to a variety of hybrid electrocatalysts to improve their activity and selectivity. Understanding the synergistic mechanism is crucial for the rational design of these types of catalysts. Here, we synthesize a MnCo2O4/Co–N–C hybrid electrocatalyst for the oxygen reduction reaction (ORR) and systematically investigate the synergy between MnCo2O4 nanoparticles and Co–N–C support. Theoretical simulations reveal that the synergy is closely related to the distance between active sites. For a pair of remote active sites, the ORR proceeds through the known 2e- + 2e- relay catalysis while the direct 4e– ORR occurs on a pair of adjacent active sites. Therefore, the formation of the undesired byproduct (H2O2) is inhibited at the interface region between MnCo2O4 and Co–N–C. This synergistic effect is further verified on an anion-exchange membrane fuel cell. The findings deepen the understanding of synergistic catalysis and will provide guidance for the rational design of hybrid electrocatalysts.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2025
·
IF 3.9
Xuying Liu,Min Zou,Yehao Yu,Yuanrui Hai,Jinyan Huang,Yunchang Fan,Yulong Zhang,Yujing Weng,Yuhe Liao
Glycolic acid (GA), a versatile compound widely used in pharmaceuticals, cosmetics, and biodegradable polymers, requires efficient and sustainable synthesis methods to meet industrial demands. This study investigates the selective oxidation of glycolaldehyde (GD) and ethylene glycol (EG) to GA over a carbon-supported platinum (Pt/C) catalyst under alkali-free conditions. Complete GD conversion with exceptional GA selectivity (99.8%) was achieved under mild conditions (30 °C, 2.5 MPa air), while EG oxidation exhibited moderate conversion (∼60%) with >90% GA selectivity. Kinetic analysis revealed distinct oxygen pressure dependencies: GD oxidation exhibited strong oxygen sensitivity, as oxygen adsorption and activation were rate-determining, whereas EG oxidation was predominantly governed by substrate concentration due to the oxygen saturation on the Pt/C surface. Mechanistic studies identified GD as a key intermediate in EG oxidation, with overoxidation pathways limiting GA selectivity at higher temperatures and concentrations. Catalyst characterization demonstrated high Pt dispersion, stable surface chemistry, and structural durability, contributing to its superior performance. This work provides a green, efficient pathway for GA production, offering valuable insights into catalyst design and process optimization for sustainable chemical manufacturing.
研究领域:
化学工程
·
催化科学
✓ 已验证
产品关联
DOI
高影响因子
INORGANIC CHEMISTRY
·
2025
·
IF 4.7
Jing Xu,Kangle Wan,Jianjie Wu,Yunchao Wu,Wei Yan,Lichuan Zhang,Yuanping Chen,Yingcong Wei
During the piezoelectric photocatalytic process, the surface curvature of the piezoelectric photocatalyst undergoes dynamic changes under the influence of external mechanical forces. However, the correlation between the surface curvature and catalytic performance remains largely unexplored. Here, we demonstrate that decreasing the radius of curvature of MoSe2 significantly enhances its piezoelectric-photocatalytic activity for C–N coupling reactions, enabling imine synthesis from benzylamine. Comprehensive characterization and DFT calculations together show that the piezoelectric effect in the curved MoSe2 structure inhibits photogenerated charge carriers from recombination, improving carrier utilization efficiency. Additionally, the surface curvature effect induced by ultrasonic driving reduces the band gap. It promotes the effective transfer of electrons from Mo atoms in MoSe2 to −NH2 in benzylamine, thereby facilitating the activation of the benzylamine molecule. As a result, the synergistic effects of the piezoelectric and curvature characteristics significantly enhance the photocatalytic performance of MoSe2 toward the C–N coupling of benzylamine. This study not only provides new insights into interfacial reaction mechanisms in piezoelectric photocatalysis but also offers a novel perspective for designing high-performance catalytic systems.
研究领域:
材料科学
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催化化学
·
理论计算
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Energy Chemistry
·
2024
·
IF 14
Dong Zhang,Minghui Zhu,Ran Qin,Peixian Chen,Maoye Yin,Dafeng Zhang,Junchang Liu,Hengshuai Li,Xipeng Pu,Peiqing Cai
Rational design of photocatalyst to maximize the use of sunlight is one of the issues to be solved in photocatalysis technology. In this study, the CuFe 2 O 4 @C/Cd 0.9 Zn 0.1 S (CFO@C/CZS) S-scheme photocatalyst with photothermal effect was synthesized by ultrasonic self-assembly combined with calcination. The dark CFO@C absorbed visible light and partly converted into heat to promote the hydrogen evolution reaction. The presence of heterojunctions inhibited the photogenerated electron-hole recombination. The graphite-carbon layer provided a stable channel for electron transfer, and the presence of magnetic CFO made recycle easier. Under the action of photothermal assistance and heterojunction, the hydrogen evolution rate of the optimal CFO@C/CZS was 80.79 mmol g −1 h −1 , which was 2.55 times and 260.61 times of that of pure CZS and CFO@C, respectively. Notably, the composite samples also exhibit excellent stability and a wide range of environmental adaptability. Through experimental tests and first-principles simulation calculation methods, the plausible mechanism of photoactivity enhancement was proposed. This work provided a feasible strategy of photothermal assistance for the development of heterojunction photocatalysts with distinctive hydrogen evolution.
研究领域:
材料科学
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环境科学
·
能源科学
✓ 已验证
DOI
高影响因子
DIAMOND AND RELATED MATERIALS
·
2024
·
IF 4.3
Linyun Zhang,Shanxin Li,Xuzhou Jiang,Hongying Yu,Yijing Sun
Carbonaceous materials have great prospects in microwave absorption due to their lightweight and corrosion resistance. However, their high conductivity leads to poor impedance matching, posing a significant challenge for obtaining outstanding microwave absorption (MA) materials from carbonaceous materials. In this work, the core-shell ZnO/C nanorods (ZCNs) are prepared by covering conductive carbon on the surface of ZnO nanorods through a simple stirring process in ambient temperature and calcination treatment. The thickness of carbon shell is carefully regulated to realize appropriate impedance matching and strong microwave dissipation capability. ZCN with 30.2 nm of carbon shell achieves outstanding microwave absorption in low frequency and broadband microwave absorption because of the synergies of optimized impedance matching and enhanced dielectric loss: the reflection loss of 49.9 dB at 6.32 GHz, and the effective absorption bandwidth of 6.4 GHz at a corresponding thickness of 2.0 mm. RCS simulation results have verified its excellent performance in practical application. This study proposes a simple and effective idea for the efficient utilization of carbonaceous materials in microwave absorption.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
·
2024
·
IF 5.8
Chuanqing Zhao,Shiqi Xia,Yizhe Lv,Huimin Qi,Shifeng Deng
Based on the micro-nano scale designs for absorbing materials, analyzing the influence of microstructures on absorbing properties is a feasible strategy to achieve efficient lightweight broadband electromagnetic wave absorbers. In this work, the silicon-containing arylacetylene resin, serving as a ceramic polymer precursor, is employed to coat SiO 2 gel. Subsequently, the PSA/SiO 2 aerogel underwent carbothermal reduction and the polymer-derived ceramics process, transforming it into a SiC/C aerogel. This SiC/C aerogel exhibits a low density of 0.2 g/cm³ and a high porosity of 68 %. The rich morphology of SiC/C aerogel is conducive to both interfacial polarization and multiple scattering, resulting in excellent impedance matching and attenuation. With a reflection loss of −52.6 dB and an effective absorption bandwidth of 6 GHz, SiC/C aerogels also achieve effective absorption in both the X and Ku bands. These results may thus be of great significance in guiding the design and mechanism investigation of high-performance.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2021
·
IF 8.128
Zijian Liao,Mingliang Ma,Yuxin Bi,Zhouyu Tong,Kwok L. Chung,Zijian Li,Yong Ma,Binglong Gao,Zhengkai Cao,Ranran Sun,Xiang Zhong
Advanced microwave absorption (MA) materials have attracted widespread attention to meet the challenges of electromagnetic (EM) pollution. Herein, MgFe 2 O 4 /MgO/C fibers were successfully prepared via electrospinning technology and carbonization , and their surfaces were coated by MoS 2 via hydrothermal method . The EM wave absorption performance of composites was enhanced due to the introduction of MoS 2 . The results showed that the EM wave absorption performance of MgFe 2 O 4 /MgO/C could not meet the requirements due to low dielectric loss and poor impedance matching. The performance of the composites was improved after coating of MoS 2 , which showed the strong wave absorption capability and the broad absorption bandwidth. The optimal reflection loss (RL) is −56.94 dB at 9.5 GHz and the effective absorption bandwidth is 3.9 GHz (8.08–11.98 GHz) with a thickness of 2.7 mm. The excellent MA performance can be mainly attributed to excellent synergistic effect between MgFe 2 O 4 /MgO/C and MoS 2 . Furthermore, MoS 2 also contributes to dielectric loss and ideal impedance matching. MgFe 2 O 4 /MgO/C@MoS 2 composites may be utilized for lightweight and high-efficient MA materials.
研究领域:
材料科学
·
电磁学
✓ 已验证
DOI
高影响因子
BIORESOURCE TECHNOLOGY
·
2024
·
IF 9.7
Qiushi Jiang,Yanjing Li,Minmin Wang,Wen Cao,Xueying Yang,Sihu Zhang,Liejin Guo
This study investigated the mediating effect of Triethanolamine on Fe@C- Rhodobacter sphaeroides hybrid photosynthetic system to achieve efficient biohydrogen production. The biocompatible Fe@C generates excited electrons upon exposure to light, releasing ferrum for nitrogenase synthesis, and regulating the pH of the fermentation environment. Triethanolamine was introduced to optimize the electron transfer chain, thereby improving system stability, prolonging electron lifespan, and facilitating ferrum corrosion. This, in turn, stimulated the lactic acid synthetic metabolic pathway of Rhodobacter sphaeroides , resulting in increased reducing power in the biohybrid system. The ternary coupling system was analyzed through the regulation of concentration, initial pH, and light intensity. The system achieved the highest total H 2 production of 5410.9 mL/L, 1.29 times higher than the control (2360.5 mL/L). This research provides a valuable strategy for constructing ferrum-carbon-based composite-cellular biohybrid systems for photo-fermentation H 2 production.
研究领域:
微生物学
·
可再生能源
·
光合作用
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2019
·
IF 8.456
Yinling Wang,Juan Wang,Dandan Wei,Maoguo Li
M–N–C electrocatalysts for the oxygen reduction reaction (ORR) have been considered as the most promising alternatives to precious metal catalysts. However, the catalytic activity of M–N–C especially in an acidic medium is still unable to meet the practical requirement, and the corresponding ORR mechanism also remains unclear. Herein, an “MOF-protective-pyrolysis” strategy was adopted to synthesize an Fe–N–C catalyst (P-FeMOF@ZIF-8) with Fe–N4 as the predominant Fe species. The P-FeMOF@ZIF-8 displays high catalytic activity in both acidic and alkaline mediums. The experimental results further reveal the different importance of the Fe species in different mediums. Based on the results, a distinct mechanism of the ORR the in acidic medium was proposed, where the synergistic effect of the Fe–N4 site and carbon in improving the kinetics of the ORR were well explained. The findings and the corresponding perspective may provide a new guidance for the design of highly efficient ORR electrocatalysts.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
PubMed
高影响因子
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