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光热协同驱动SrTiO_(x)负载CuCo催化CO_(2)-CH_(4)和H_(2)O共转化制备C_(2)含氧化合物
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作者 朱彦儒 张志军 +7 位作者 张健 蒋双江 安哲 宋红艳 舒心 习卫 郑黎荣 何静 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第6期164-178,共15页
催化转化CO_(2)为乙醇、乙醛等高值C_(2)含氧化合物是一个具有科学意义和经济价值的化学过程.然而,由于碳氧键活化难、多电子(≥10)转移过程复杂以及C–C偶联动力学缓慢等问题,导致该过程的反应效率低.CO_(2)因热力学稳定、动力学惰性,... 催化转化CO_(2)为乙醇、乙醛等高值C_(2)含氧化合物是一个具有科学意义和经济价值的化学过程.然而,由于碳氧键活化难、多电子(≥10)转移过程复杂以及C–C偶联动力学缓慢等问题,导致该过程的反应效率低.CO_(2)因热力学稳定、动力学惰性,其加氢活化通常是强吸热过程(如CO_(2)活化成CO的ΔH_(2)98K=42.1 kJ mol^(–1)),因此需要在一定温度下才能获得满意的CO_(2)转化率.与此同时,CH_(4)作为碳化学价态最低的化合物,其氧化过程与CO_(2)的还原过程可以耦合,共同转化为高值化学品,同样受到了广泛关注.但CH_(4)的活化同样需要高温等苛刻条件,因此,在温和条件下共转化CO_(2)和CH_(4),选择性构建高值C_(2)含氧化合物,是一个重要且具有挑战性的研究方向.本文提出利用光外场和水活化策略,即利用光解水产生的活性氢和活性氧物种,在温和条件下实现CO_(2)和CH_(4)的高效、高选择性活化及共转化.光照下,在钛酸锶(SrTiO_(x))负载的具有丰富Cu-Co界面的催化剂上,光解水产生的活性氢和活性氧物种,分别活化CO_(2)的碳氧键和CH_(4)的碳氢键,在Cu和Co位点上分别形成*CH_(x)O和*CH_(3)物种,进而通过C–C偶联高效生成C_(2)含氧化合物.在200°C和光照条件下,C_(2)含氧化合物(CH_(3)CHO和CH_(3)CH_(2)OH)的生成速率高达2.05 mmol g^(–1)h^(–1),同时产物选择性>86%.同位素标记、红外光谱示踪的原位反应和催化实验结果表明,紫外光激发下,SrTiO_(x)上的金属位点促进了光催化水裂解,生成活性氢和活性氧物种(该过程为整个反应的决速步骤).活性氢物种使吸附在SrTiO_(x)上的CO_(2)活化并转化为CO;随后,在CuI/Cu^(0)对上,CO加氢生成*CH_(x)O中间体.另一方面,在Co位点上,CH_(4)与活性氧物种发生反应,被活化为*CH_(3)中间体.最后,*CH_(x)O与*CH_(3)两种中间体在CuCo界面处发生C–C偶联反应,进而形成C_(2)含氧化合物.与传统的热催化下的CO_(2)和CH_(4)共转化过程相比,光热协同策略使该反应温度降低了超过600°C,并且反应活化能降低了约12 kJ mol^(–1),表明光热协同策略不仅可以大幅降低反应温度,还能极大提升反应动力学,为强吸热反应过程提供了一条提效降耗的反应途径.综上所述,本工作通过构建结构精准可控的SrTiO_(x)负载的CuCo邻近界面结构,同时利用光解水产生的活性氢/氧物种促进CO_(2)和CH_(4)活化,实现了高效定向共转化.本文提出的“光热协同”策略为高效活化CO_(2)制高值化学品提供了新的研究思路,同时显著降低了能耗,对解决强吸热催化反应高能耗问题提供了参考. 展开更多
关键词 光热协同 CO_(2)和CH_(4)共转化 SrTiO_(x)负载CuCo 水裂解 C_(2)含氧化合物
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Highly dispersed MgInCe-mixed metal oxides catalyzed direct carbonylation of glycerol and CO_(2)into glycerol carbonate
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作者 Xufang Chen Xin Shu +5 位作者 yanru zhu Jian Zhang Zhigang Chai Hongyan Song Zhe An Jing He 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第8期153-163,共11页
Glycerol carbonate,an important glycerol value-added product,has been widely used as an active intermediate and inert solvent in the synthesis of cosmetics,detergents,chemical intermediates,polymers,and so on.The dire... Glycerol carbonate,an important glycerol value-added product,has been widely used as an active intermediate and inert solvent in the synthesis of cosmetics,detergents,chemical intermediates,polymers,and so on.The direct carbonylation from glycerol with CO_(2)is considered a promising route,but still tough work due to the thermodynamic stability and the kinetic inertness of CO_(2).In this work,highlyselective direct carbonylation of glycerol and CO_(2)into glycerol carbonate has been achieved over highly dispersed MgInCe-mixed metal oxides(MgInCe-MMO),which were prepared through the topological transformation derived from the MgInCe-layered double hydroxides(MgInCe-LDHs).By precisely modulating the surface basic-acidic properties and the oxygen vacancies,an efficient carbonylation of glycerol with CO_(2)has been achieved with a selectivity of up to>99%to glycerol carbonate.Deep investigation into the synergistic catalysis of base-acid sites and oxygen vacancies has been clarified. 展开更多
关键词 Catalytic reaction engineering Glycerol carbonate Direct carbonylation from glycerol Carbon dioxide Mixed metal oxides Synergistic catalysis
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Untargeted and targeted mass spectrometry reveal the effects of theanine on the central and peripheral metabolomics of chronic unpredictable mild stress-induced depression in juvenile rats 被引量:2
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作者 yanru zhu Feng Wang +4 位作者 Jiatong Han Yunli Zhao Miao Yu Mingyan Ma Zhiguo Yu 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2023年第1期73-87,共15页
L-theanine has been shown to have a therapeutic effect on depression.However,whether L-theanine has an excellent preventive effect on depression in children and adolescents and what its mechanism is have not been well... L-theanine has been shown to have a therapeutic effect on depression.However,whether L-theanine has an excellent preventive effect on depression in children and adolescents and what its mechanism is have not been well explained.Given the complexity of the pathogenesis of depression,this study investigated the preventive effect and mechanism of L-theanine on depression in juvenile rats by combining serum and hippocampal metabolomic strategies.Behavioral tests,hippocampal tissue sections,and serum and hippocampal biochemical indexes were studied,and the results confirmed the preventive effect of Ltheanine.Untargeted reversed-phase liquid chromatography-quadrupole-time-of-flight mass spectrometry and targeted hydrophilic interaction liquid chromatography-triple quadrupole mass spectrometry were developed to analyze the metabolism changes in the serum and hippocampus to screen for potential biomarkers related to L-theanine treatment.The results suggested that 28 abnormal metabolites in the serum and hippocampus that were considered as potential biomarkers returned to nearnormal levels after L-theanine administration.These biomarkers were involved in various metabolic pathways,mainly including amino acid metabolism and lipid metabolism.The levels of amino acids and neurotransmitters in the phenylalanine,tryptophan,and glutamic acid pathways were significantly reduced after L-theanine administration compared with chronic unpredictable mild stress-induced rats.In summary,L-theanine had a significant preventive effect on depression and achieved its preventive results on depression by regulating various aspects of the body,such as amino acids,lipids,and inflammation.This research systematically analyzed the mechanism of L-theanine in preventing depression and laid the foundation for applying L-theanine to prevent depression in children and adolescents. 展开更多
关键词 L-THEANINE DEPRESSION Metabolomics Liquid chromatography-mass spectrometry
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Low temperature one-pot synthesis of 1,1-diethoxyethane from ethanol on Bi/BiCeO_(x)with strong metal-support interactions
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作者 Zhe An Jiayu Liu +5 位作者 Meng Cao Jian Zhang yanru zhu Hongyan Song Xu Xiang Jing He 《Nano Research》 SCIE EI CSCD 2023年第3期3709-3718,共10页
The direct conversion of ethanol to 1,1-diethoxyethane(DEE)through one-pot dehydrogenation-acetalization has attracted broad interest from both academia and industry.Based on thermodynamics,the oxidative dehydrogenati... The direct conversion of ethanol to 1,1-diethoxyethane(DEE)through one-pot dehydrogenation-acetalization has attracted broad interest from both academia and industry.Based on thermodynamics,the oxidative dehydrogenation of alcohol to acetaldehyde requires high temperature to activate oxygen to realize the C-H cleavage,while the acetalization of acetaldehyde with ethanol is exothermic reversible reaction favorable at low temperature.The mismatching of the reaction condition for the two consecutive steps makes it a great challenge to achieve both high ethanol conversion and high DEE selectivity.This work reports a highly efficient bi-functional catalysis by Bi/BiCeO_(x)for one-pot oxidative dehydrogenation-acetalization route from ethanol to DEE under 150℃and ambient pressure,affording a selectivity of 98.5%±0.5%to DEE at an ethanol conversion of 87.0%±1.0%.An efficient tandem catalysis has been achieved on the interfacial Bi^(δ)+-Ov-Ce^(III)sites in Bi/BiCeO_(x)established by strong metal-support interaction,in which Biδ+-Ov-sites contribute to the oxidative dehydrogenation of ethanol at mild temperature,and-Ov-CeIII sites to the subsequent acetalization between the generated acetaldehyde and ethanol. 展开更多
关键词 ethanol conversion 1 1-diethoxyethane strong metal-support interaction Biδ+-Ov-CeIII sites
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Efficient selective activation of sorbitol C–O bonds over C–C bonds on CoGa(221)generated by lattice-induction strategy
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作者 Ying Kong yanru zhu +5 位作者 Zhe An Jian Zhang Xin Shu Hongyan Song Qipeng Yuan Jing He 《Nano Research》 SCIE EI CSCD 2023年第5期6200-6211,共12页
Sorbitol is a primary platform compound in the conversion of cellulose.The conversion of sorbitol to C_(6) hydrocarbons requires a complete cleavage of C–O bonds and meanwhile the inhibition of C–C cleavage.Here,we ... Sorbitol is a primary platform compound in the conversion of cellulose.The conversion of sorbitol to C_(6) hydrocarbons requires a complete cleavage of C–O bonds and meanwhile the inhibition of C–C cleavage.Here,we demonstrated an efficient selective cleavage of C–O over C–C bond on the(221)facet of supported CoGa.A selectivity of 94%to C_(6) hydrocarbon with conversion of 97%has been achieved.The selective C–O cleavage was demonstrated by tuning the exposed facet as(221)or(110).The supported CoGa was prepared simply by reduction of Co and Ga-containing layered double hydroxides(CoZnGaAl-LDHs),the exposed facets of CoGa crystallites were controlled by tailoring the temperature-programmed rate in the reduction.By reducing CoZnGaAl-LDHs,CoGa(221)was exposed with a temperature-programmed rate of 5℃/min under the induction of ZnO lattice,while CoGa(110)was exposed with a rate of 10℃/min. 展开更多
关键词 biomass supported CoGa facet exposure preferred C–O activation liquid hydrocarbons
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晶格受限Ga~Ⅲ诱导Pt高分散及其催化重整性能 被引量:2
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作者 王文龙 安哲 +2 位作者 朱彦儒 宋红艳 何静 《中国科学:化学》 CAS CSCD 北大核心 2020年第2期306-314,共9页
针对催化重整反应中由于Pt分散度低引起氢解等副反应导致异构烷烃选择性差的问题,本文提出利用受限于层状双金属氢氧化物(LDHs)主体层板晶格内的GaⅢ对Pt的诱导效应控制Pt在载体表面原子水平高分散,Pt分散度达到98.8%,其中单原子Pt比例... 针对催化重整反应中由于Pt分散度低引起氢解等副反应导致异构烷烃选择性差的问题,本文提出利用受限于层状双金属氢氧化物(LDHs)主体层板晶格内的GaⅢ对Pt的诱导效应控制Pt在载体表面原子水平高分散,Pt分散度达到98.8%,其中单原子Pt比例占68%.应用于正庚烷重整反应,高分散的Pt能够有效地抑制氢解副反应和芳构化反应,并大幅度提高异构选择性,在50%转化率下获得了53%的i-C7选择性,同时C1~4产物选择性小于20%. 展开更多
关键词 PT催化剂 高分散 正庚烷重整 晶格限域 Ga助剂 层状双金属氢氧化物
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NiCu bimetallic catalysts derived from layered double hydroxides for hydroconversion of n-heptane
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作者 yanru zhu Minghuan Yang +4 位作者 Zhen Zhang Zhe An Jian Zhang Xin Shu Jing He 《Chinese Chemical Letters》 SCIE CAS CSCD 2022年第4期2069-2072,共4页
Supported NiCu bimetallic catalysts have been produced in-situ on commercial Al_(2)O_(3)by using layered double hydroxides as precursors. The resulting catalysts show a uniform Ni and Cu distribution, thus providing g... Supported NiCu bimetallic catalysts have been produced in-situ on commercial Al_(2)O_(3)by using layered double hydroxides as precursors. The resulting catalysts show a uniform Ni and Cu distribution, thus providing good activity and selectivity in the reforming reaction of n-heptane. The catalytic performance has been found to depend on the Cu/Ni ratio, revealing the synergic catalysis between homogeneously dispersed Ni and Cu sites. The good catalysis of Ni Cu bimetallic catalysts makes it possible to partly or even completely replace Pt with NiCu bimetallic catalysts. 展开更多
关键词 n-Heptane reforming NiCu bimetallic catalysts Synergic catalysis Uniform distribution Layered double hydroxides
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