CHEMICAL ENGINEERING JOURNAL
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2020
·
IF 10.652
Min Chen,Honghong Wang,Xueyan Chen,Fei Wang,Xiaoxiao Qin,Changbin Zhang,Hong He
Photocatalysis is regarded as a promising method for indoor formaldehyde (HCHO) removal, and there remains a strong demand for the development of highly efficient photocatalysts for HCHO oxidation under visible light. Herein, by grafting nano CuO x clusters onto TiO 2 , the higher performance is achieved over Cu-TiO 2 for the photocatalytic oxidation of HCHO under visible light compared with the typical photocatalysts N-TiO 2 and g-C 3 N 4 . It is found that the presence of water greatly promotes the activity of HCHO oxidation on Cu-TiO 2 . The characterization results indicate that the CuO x clusters on TiO 2 exhibit high redox reversibility between Cu (II) and Cu (I) and greatly facilitate the migration of electrons. The mechanism of photocatalytic oxidation of HCHO was explored by using in situ DRIFTS measurements and DFT calculations. It is shown that HCHO is firstly oxidized to dioxymethylene (DOM), and then DOM is transformed into formate species under visible light irradiation. DFT calculations results indicate that the OH species are responsible for surface formate decomposition, which is the rate-determining step, while O 2 − radical is not active in formate decomposition. Our findings improve the understanding on the photocatalytic oxidation of HCHO, and the Cu-TiO 2 catalyst is a promising candidate for practical application in indoor air purification.
研究领域:
环境科学
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材料科学
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产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2024
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IF 7.1
Xiang Hui,Liguo Wang,Jianhui Shi,Tiping Wei,Fengqin Guo,Yan Cao,Peng He,Jiajun Zhang,Huiquan Li
The methoxycarbonylation of amines into carbamates via the construction of a C–N bond is an important reaction in pharmaceutical and fine chemical syntheses. However, the methoxycarbonylation of amines with dimethyl carbonate (DMC) without metal-based catalysts or other base catalysts has rarely been studied, and the reaction mechanisms remain underexplored. Herein, efficient methoxycarbonylation of biobased pentanediamine (PDA) with DMC promoted by water is proposed. The addition of water as a catalyst resulted in a 4-fold increase in yield. The conducted kinetic studies showed that proton transfer from PDA to methoxy occurs through the hydrogen bond between the zwitterionic intermediate and water. In situ analyses have shown that OH– and water form hydrogen bonds with the ether O atom of DMC and hydroxyl H atoms of PDA, synergistically promoting the elimination of the methoxy group. The addition of water reduced the energy barrier of the methoxy group elimination from 16.3 to 0.6 kcal/mol, confirming the results of theoretical computations. Furthermore, the methyl (5-aminophenyl)carbamate intermediate was recycled into dimethyl pentane-1,5-diyldicarbamate without the use of an additional catalyst, which was mediated by the hydrogen bond between PDA and methyl (5-aminophenyl)carbamate. The reported mild methoxycarbonylation of biobased PDA under metal-free conditions is a green and sustainable method of synthesizing biobased dicarbamate.
研究领域:
有机化学
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绿色化学
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产品关联
DOI
高影响因子
ChemCatChem
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2013
·Vol. 5
·期 7
·1935-1940
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IF 5.181
Zong-Bo Xie,Na Wang,Long-Hua Zhou,Fang Wan,Ting He,Zhang-Gao Le,Xiao-Qi Yu
Graphical Lip synthing: A lipase-catalyzed, green, and efficient approach for the cross-aldol reaction promoted by water with high yield and good stereoselectivity is described. PPL, lipase from porcine pancreas, is first reported to catalyze direct asymmetric aldol reactions between aromatic aldehydes and cyclic ketones. More importantly, the catalytic activity of PPL was greatly promoted by a small quantity of water at 37 °C. A wide range of aromatic aldehydes reacted with cyclic ketones to provide the corresponding aldol products with high yields (up to 99 %) and moderate to good stereoselectivity (up to 90 % ee and 99:1 dr ).
研究领域:
生物化学
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有机合成
✓ 已验证
产品关联
DOI
高影响因子
Molecular Catalysis
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2024
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IF 3.9
Xing Gao,Ying Ma,Yingying Ruan,Wenna Zhang,Shihao Zhang,Wenxue Xiong,Dong Tian,Shiliu Yang,Pei Fan,Yanhui Yang,Yihu Dai
Non-noble metal-catalyzed selective C O hydrogenation of α,β-unsaturated aldehydes to corresponding alcohols is chemically atom economic and practically feasible. This work reports hydrotalcite-derived Co-based catalysts for catalyzing aqueous phase selective hydrogenation reaction of cinnamaldehyde to cinnamyl alcohol. The structure characterizations demonstrate the phase transition from hydrotalcite to co-existed CoO x and metallic Co 0 in the optimal Co 2 Al-H 2 -400 catalyst. It exhibits superior catalytic activity and selectivity relative to other as-obtained Co catalysts, because of the synergy effect of Co 2+ sites to promote the adsorptive activation of C O group and small-size Co 0 sites to facilitate the activating dissociation of hydrogen. Furthermore, the catalytic role of water has also been explored. Adopting water as pure solvent and partially adding water into organic solvent can both effectively enhance the activity and selectivity. Such reaction environment may induce creation of more intermolecular hydrogen bonds for promoting the hydrogen transfer and thus boosting the hydrogenation reaction.
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
Chem Catalysis
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2023
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IF 9.4
Zhongliang Huang,Siyuan Hu,Yinan Xu,Jinxin He,Dongren Cai,Kang Sun,Jianchun Jiang,Guowu Zhan
Summary The interfacial sites of metal-support catalysts are crucial for catalytic reactions. Herein, we designed well-defined N-Co 3 O 4 /Pt catalysts with N-tailoring metal-support interfaces to promote catalytic activity toward CO oxidation under humid environments. A series of N-Co 3 O 4 /Pt catalysts were fabricated using ZIF-67 nanocubes as self-sacrificing templates, which showed exceptionally high catalytic activity in low-temperature CO oxidation. In situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) study indicates that H 2 O molecules undergo dissociative adsorption to form active –OH species (Co 3+ –OH–Pt). Isotopic labeling technique indicates that H 2 O molecules (or –OH groups) contribute to ∼65% of CO 2 production in CO oxidation. Moreover, the amount of N dopant that stabilized the Co 3+ –OH–Pt species was highly dependent on the H 2 O-soaking conditions of ZIF-67/Pt. Density functional theory (DFT) calculations suggest that the COOH ∗ pathway of CO oxidation over the N-Co 3 O 4 /Pt interface is energetically favorable in humid conditions. In particular, the N doping could stabilize the Co 3+ –OH–Pt interface and simultaneously reduce the energy barrier of CO 2 formation from COOH ∗ intermediates.
研究领域:
催化化学
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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
Environmental Progress & Sustainable Energy
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2018
·Vol. 37
·期 6
·2026-2033
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IF 1.326
Ke Wang,Ji Sun,Pengfei Zhao
The development of novel Li 4 SiO 4 -based sorbents is hampered by a lack of understanding of the mechanisms governing CO 2 adsorption on the Li 4 SiO 4 surface. In this work, the adsorption of CO 2 and flue gas components (such as H 2 O and SO X (SO 2 and SO 3 )) on a simulated Li 4 SiO 4 surface was investigated using ab initio-based energetic calculations. The Li 4 SiO 4 surface was modeled by a cluster of lithium silicate, in which the atoms were unsaturated to simulate the active sites. Furthermore, Fourier transform infrared (FTIR) spectra were also analyzed. The calculated results showed that three possible configurations were determined: CO 2 weakly sorbed on the oxygen sites of Li 4 SiO 4 through physisorption; a carbonate species appeared, which was characterized by chemisorption; and a linear cluster of Li + -O = C=O formed, having the largest sorption energy. These three possible pathways were likewise in accordance with the FTIR results. Moreover, a pre-chemisorption of water on Li 4 SiO 4 resulted in promoted CO 2 capture, while the presence of competitive SO X sorption on the same active sites as CO 2 sorption showed an inhibition effect. The results clarify the complex adsorption mechanisms on the Li 4 SiO 4 surface. © 2018 American Institute of Chemical Engineers Environ Prog, 37: 1901–1907, 2018
研究领域:
化学工程
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环境科学
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产品关联
DOI
高影响因子
Molecular Catalysis
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2018
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IF 0
Wen-Yu Liang,Lei Liu,Qing Zhou,Da Yang,Yong Lu,Ye Liu
The Pd-catalyzed alkoxycarbonylation of alkenes using water as a promoter has been scarcely reported before. Herein, water instead of Brønsted/Lewis acid was found to effectively improve the catalytic performance of Pd(MeCN) 2 Cl 2 -Xantphos system for alkoxycarbonylation of alkenes. Under the optimal conditions, the best yield of 97% was obtained for the target products (methyl 3-phenylpropanoate and methyl 2-phenylpropanoate) with L/B of 4.3 and TON of 192. With the involvement of water, Pd(MeCN) 2 Cl 2 -Xantphos system also exhibited the moderate to good generality to alkoxycarbonylation of different kinds of alkenes with alcohols. The in situ high pressure FT-IR analysis verified that water played an important role in promoting formation and stability of Pd H active species which was responsible for the efficient alkoxycarbonylation of alkenes. In addition, the ligand effect of Xantphos on this reaction was discussed.
研究领域:
化学
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催化反应
✓ 已验证
DOI
ADVANCED MATERIALS
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2024
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IF 27.4
Hao Fu,Hongjie Liu,Xiyang Wang,Wenhua Zhang,Hui Zhang,Yunhong Luo,Xianwang Deng,Graham King,Ning Chen,Liwei Wang,Yimin A. Wu
Understanding the water-involved mechanism on metal oxide surface and the dynamic interaction of water with active sites is crucial in solving water poisoning in catalytic reactions. Herein, this work solves this problem by designing the water-promoted function of metal oxides in the ethanol oxidation reaction. In situ multimodal spectroscopies unveil that the competitive adsorption of water-dissociated *OH species with O 2 at Sn active sites results in water poisoning and the sluggish proton transfer in CoO-SnO 2 imparts water-resistant effect. Carbon material as electron donor and proton transport channel optimizes the Co active sites and expedites the reverse hydrogen spillover from CoO to SnO 2 . The water-promoted function arises from spillover protons facilitating O 2 activation on the SnO 2 surface, leading to crucial *OOH intermediate formation for catalyzing C-H and C-C cleavage. Consequently, the tailored CoO-C-SnO 2 showcases a remarkable 60-fold enhancement in ethanol oxidation reaction compared to bare SnO 2 under high-humidity conditions.
研究领域:
催化化学
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材料科学
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表面化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Environmental Chemical Engineering
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2021
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IF 5.909
Yu-Nong Li,Qi-Neng Xu,Lei-Feng Wu,Yao-Hui Guo,Huan Yue,Jun Zhou,Chang-Lei Ge,Hao-Ran Chang
On the basis of a synergistic strategy for CO 2 activation and conversion, a water-promoted selective synthesis of 5-aryl-2-oxazolidinones from aziridines and CO 2 has been exploited in a metal- and base-free system in confined nanospaces of hierarchical porous silica, affording moderate to good conversions and yields. In this process, carbonic acid in-situ generated interacts with and ingeniously activates the aziridine ring, facilitating its subsequent transformation and promoting the selectivity of 5-substituted products. DFT calculations , FTIR spectroscopy and pH value monitoring reveal that the excellent 5-postion regio-selectivity is dictated by kinetics, which is attributed to the formation of a latent benzyl carbocation in the transition state. The confined nanospaces of hierarchical porous silica can be considered as plenty of nanoreactors, which would change concentrations of reagents and activation parameters, stabilize transition states and enhance the kinetics process. This environment-friendly system provides a synergistic strategy of optimizing both the chemical function and physical microenvironment to enhance CO 2 activation, and enriches the carbon capture and utilization (CCU) coupling process by conversion of the waste (water-fixed CO 2 ) into value-added compounds.
研究领域:
化学工程
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材料科学
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环境科学
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DOI
高影响因子
JOURNAL OF CATALYSIS
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2023
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IF 7.3
Liyong Ding,Yukun Zhao,Youji Li,Chengsheng Ge,Liang Lv,Hongwei Ji,Wenjing Song,Chuncheng Chen,Jincai Zhao
During TiO 2 -based photocatalysis, the presence of water usually leads to the unselective degradation of organic compounds due to the uncontrollable formation of water-derived radical species. Here we report that the presence of water dramatically enhances the selectivity in photocatalytic oxidation of sulfides to sulfoxides over TiO 2 . H 2 18 O-isotope labelling experiments reveal that both O 2 and H 2 18 O contribute to the oxygen atoms in the formed sulfoxides and sulfones. Moreover, at the beginning of the oxidation of sulfides, water serves as the main source of the oxygen atom, while the contribution of O 2 increases with the irradiation time. We uncover two roles of water in sulfides oxidation: to act as oxygen source in the oxidation of sulfides to sulfoxides; to provide protons to inhibit the further oxidation of sulfoxides. This study deepens our understanding of roles of water in photocatalytic oxidation of sulfides and offers a new strategy to optimize photocatalytic selective oxidation .
研究领域:
化学
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环境科学
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材料科学
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产品关联
DOI
高影响因子
Biomass Conversion and Biorefinery
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2020
·Vol. 12
·期 6
·2017-2025
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IF 2.602
Wang Yun,Liang Xin-Yi,Chen Xin-Yi,Liang Zhi-Hui,Cheng Hong,Li Xiang,Li Li-Ling
Bovine pancreatic lipase (BPL) is reported to catalyze direct asymmetric aldol reactions between aromatic aldehydes and cyclic ketones in water at 50 °C, and water can greatly promote the catalytic activity and selectivity of BPL. A wide range of aromatic aldehydes reacted with cyclic ketones to provide the corresponding aldol products with high yields (up to 93.7%) and moderate to good stereoselectivity (up to 99% ee and 1:99 dr).
研究领域:
生物化学
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有机合成
✓ 已验证
DOI
高影响因子
CHINESE JOURNAL OF CHEMICAL ENGINEERING
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2022
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IF 3.898
Yuxin Wu,Zhuo Chen,Xiaohui Zhang,Jian Chen,Yundong Wang,Jianhong Xu
Carbon dioxide (CO 2 ) utilization and fixation have become one of the most important research areas nowadays due to the increase of global greenhouse effect. Cyclic carbonate, which is widely used in various fields, can be synthesized by fixation of CO 2 with epoxide in industry. Moreover, the synthesis of cyclic carbonate is a 100% atom economical reaction, which makes it eco-friendly and promising. To enhance the reaction efficiency and safety, a microreaction system was used as the platform for cycloaddition reaction. In this work, tetrabutylammonium bromide (TBAB) was chosen as catalyst, and propylene oxide (PO) as a mode substrate. Interestingly, the addition of water can increase the propylene carbonate (PC) yield and decrease the activation energy considerably, proving water as catalyst promoter for PC synthesis. PC yield and selectivity could reach 91.6% and 99.8%, respectively. The Influence factors and kinetic equation for CO 2 cycloaddition were obtained as well.
研究领域:
化学工程
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环境科学
✓ 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）