This study used a Polyindole in combination with TiO2 nanocatalyst as an efficient heterogeneous catalyst to carry out a multi-component Hantzsch reaction involving different aromatic aldehydes with methyl acetoacetat...This study used a Polyindole in combination with TiO2 nanocatalyst as an efficient heterogeneous catalyst to carry out a multi-component Hantzsch reaction involving different aromatic aldehydes with methyl acetoacetate, and aqueous ammonium to create 1,4-dihydropyridine derivatives under solvent free condition at ambient temperature. A broad range of aldehydes and methyl acetoacetates, ranging from heteroaromatic to polyaromatic one, with high level of functional group tolerance can be used to provide the desired products possessing relevant medicinal moiety in high yields. This technology has prospective advantages over current protocols, including the utilization of a cheap, stable, recyclable, and safe catalyst, quicker reaction times with higher yields and simple product isolation.展开更多
A simple and practical ultrasonically synthetic strategy for the preparation of rare-earth based catalyst, nanostructured NiFe2-xEuxO4 was developed. The structtre of NiFe2-xEuxO4 was characterized by various analyses...A simple and practical ultrasonically synthetic strategy for the preparation of rare-earth based catalyst, nanostructured NiFe2-xEuxO4 was developed. The structtre of NiFe2-xEuxO4 was characterized by various analyses such as X-ray diffraction （XRD）, scanning electron microscopy （SEM） and fourier transform infrared spectroscopy （FT-IR）. The catalytic performance of NiFe2-xEuxO4 was evaluated for the synthesis of benzimidazoles, benzoxazoles and benzothiazoles under ultrasonic irradiation. All reactions were completed in short times and all products were obtained in good to excellent yields in presence of the rare-earth based catalyst. Besides, NiFe2-xEuxO4 could be recovered for 6 times without noticeably decreasing the catalytic activity.展开更多
A general method is developed to prepare durable hybrid nanocatalysts by nanostructuring the surface of gold wires via simple alloying and dealloying. The resulting nanoporous gold/Au （NPG/Au） wire catalysts possess...A general method is developed to prepare durable hybrid nanocatalysts by nanostructuring the surface of gold wires via simple alloying and dealloying. The resulting nanoporous gold/Au （NPG/Au） wire catalysts possess nanoporous skins with their thicknesses on robust metal wires specified in a highly controllable manner. As a demonstration, the as-obtained NPG/Au was shown to be a highly active, chemo-selective, and recyclable catalyst for the reduction of nitro com- pounds and azides using organosilanes as reducing agents.展开更多
Recent developments in nanochemistry offer precise morphology control of nanomaterials, which has significant impacts in the field of heterogeneous catalysis. Rational design of bifunctional catalysts can influence va...Recent developments in nanochemistry offer precise morphology control of nanomaterials, which has significant impacts in the field of heterogeneous catalysis. Rational design of bifunctional catalysts can influence various aspects of catalytic properties. In this review, a new class of bifunctional catalysts with a metal@silica yolk-shell nanostructure is introduced. This structure has many advantages as a heterogeneous catalyst since it ensures a homogeneous environment around each metal core, and particle sintering is effectively eliminated during high temperature reactions. The catalysts exhibit high activity and recyclability in gas- and solution-phase reactions. It is anticipated that appropriate selection of bifunctional components and optimal structural control will significantly further enhance the catalytic properties, and enable target reaction-oriented development of new catalysts.展开更多
With the continuous development of nanomaterials in recent years,the application of nanocatalysts in catalytic ozone oxidation has attracted more and more researchers’attention due to their excellent catalytic proper...With the continuous development of nanomaterials in recent years,the application of nanocatalysts in catalytic ozone oxidation has attracted more and more researchers’attention due to their excellent catalytic properties.In this review,we systematically summarized the current research status of nanocatalysts mainly involving material categories,mechanisms and catalytic efficiency.Based on summary and analysis,we found most of the reported nanocatalysts were in the stage of laboratory research,which was caused by the nanocatalysts defects such as easy aggregation,difficult separation,and easy leakage.These defects might result in severe resource waste,economic loss and potentially adverse effects imposed on the ecosystem and human health.Aiming at solving these defects,we further analyzed the reasons and the existing reports,and revealed that coupling nano-catalyst and membrane,supported nanocatalysts and magnetic nanocatalysts had promising potential in solving these problems and promoting the actual application of nanocatalysts in wastewater treatment.Furthermore,the advantages,shortages and our perspectives of these methods are summarized and discussed.展开更多
Environmental pollution,such as water contamination,is a critical issue that must be absolutely addressed.Here,three different morphologies of tungsten-based photocatalysts(WO_(3)nanorods,WO_(3)/WS_(2)nanobricks,WO_(3...Environmental pollution,such as water contamination,is a critical issue that must be absolutely addressed.Here,three different morphologies of tungsten-based photocatalysts(WO_(3)nanorods,WO_(3)/WS_(2)nanobricks,WO_(3)/WS_(2)nanorods)are made using a simple hydrothermal method by changing the solvents(H_(2)O,DMF,aqueous HCl solution).The as-prepared nanocatalysts have excellent thermal stability,large porosity,and high hydrophilicity.The results show all materials have good photocatalytic activity in aqueous media,with WO_(3)/WS_(2)nanorods(NRs)having the best activity in the photodegradation of bisphenol A(BPA)under visible-light irradiation.This may originate from increased migration of charge carriers and effective prevention of electron–hole recombination in WO_(3)/WS_(2)NRs,whereby this photocatalyst is able to generate more reactive·OH and·O_(2)^(–)species,leading to greater photocatalytic activity.About 99.6% of BPA is photodegraded within 60 min when using 1.5 g/L WO_(3)/WS_(2)NRs and 5.0 mg/L BPA at pH 7.0.Additionally,the optimal conditions(pH,catalyst dosage,initial BPA concentration)for WO_(3)/WS_(2)NRs are also elaborately investigated.These rod-like heterostructures are expressed as potential catalysts with excellent photostability,efficient reusability,and highly active effectivity in different types of water.In particular,the removal efficiency of BPA by WO_(3)/WS_(2)NRs reduces by only 1.5% after five recycling runs and even reaches 89.1%in contaminated lake water.This study provides promising insights for the nearly complete removal of BPA from wastewater or different water resources,which is advantageous to various applications in environmental remediation.展开更多
This study focuses on drawing a hydrothermal synthesis process map for Co3O4 nanoparticles with various morphologies and investigating the effects of Co3O4 nanocatalyst morphology on CO oxidation.A series of cobalt-hy...This study focuses on drawing a hydrothermal synthesis process map for Co3O4 nanoparticles with various morphologies and investigating the effects of Co3O4 nanocatalyst morphology on CO oxidation.A series of cobalt-hydroxide-carbonate nanoparticles with various morphologies（i.e.,nanorods,nanosheets,and nanocubes） were successfully synthesized,and Co3O4 nanoparticles were obtained by thermal decomposition of the cobalt-hydroxide-carbonate precursors.The results suggest that the cobalt source is a key factor for controlling the morphology of cobalt-hydroxide-carbonate at relatively low hydrothermal temperatures（≤ 140℃）.Nanorods can be synthesized in CoCl2 solution,while Co（NO3）2 solution promotes the formation of nanosheets.Further increasing the synthesis temperature（higher than 140 ℃） results in the formation of nanocubes in either Co（NO3）2 or CoCl2 solution.The reaction time only affects the size of the obtained nanoparticles.The presence of CTAB could improve the uniformity and dispersion of particles.Co3O4 nanosheets showed much higher catalytic activity for CO oxidation than nanorods and nanocubes because it has more abundant Co^（3＋） on the surface,much higher reducibility,and better oxygen desorption capacity.展开更多
Nano titania-supported sulfonic acid（n-TSA） has found to be a highly efficient, eco-friendly and recyclable heterogeneous nanocatalyst for the solvent-free synthesis of 2,4,6-triarylpyridines through one-pot three-c...Nano titania-supported sulfonic acid（n-TSA） has found to be a highly efficient, eco-friendly and recyclable heterogeneous nanocatalyst for the solvent-free synthesis of 2,4,6-triarylpyridines through one-pot three-component reaction of acetophenones, aryl aldehydes and ammonium acetate. This reported method illustrates several advantages such as environmental friendliness reaction conditions,simplicity, short reaction time, easy work up, reusability of catalyst and high yields of the products. One new compound is reported too. Furthermore, the catalyst could be recycled after a simple work-up, and reused at least six times without substantial reduction in its catalytic activity.展开更多
Methyl formate is one of the most important intermediates in C1 chemistry, which has been employed in a wide range of industrial applications. Current synthesis methods for methyl formate mainly include esterification...Methyl formate is one of the most important intermediates in C1 chemistry, which has been employed in a wide range of industrial applications. Current synthesis methods for methyl formate mainly include esterification of methanol and formic acid, liquid-phase methanol carbonylation, oxidative dehydrogenation of methanol, one-step syngas synthesis, and carbon dioxide hydrogenation and condensation with methanol, Liquid-phase methanol carbonylation is currently a main commercially viable process devel- oped by BASF Corp, for the industrial production of methyl formate. Recently, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences has developed a new synthesis method to con- vert coal to methyl formate （denoted as CTMF）, Different from the liquid-phase methanol carbonylation using homogeneous catalysts, CTMF method features with vapor-phase methanol carbonylation using het- erogeneous nanocatalysts, which can effectively utilize the coal-based syngas and produce value-added fine chemicals （i.e., methyl formate）. The newly developed method not only provides a new methyl for- mate synthesis technology but also contributes to the development of strategies for synthesizing valuable chemicals from coal. In this review, we firstly provide introduction on the development of existing methyl formate synthesis methods and then highlight the research progress of CTMF method. Finally, a perspec- tive on the future of CTMF is given,展开更多
A novel metal-free bulk nanocatalyst, S--N-codoped hollow carbon nanosphere/ graphene aerogel （SNC-GA-1000）, has been successfully fabricated using a facile and clean solid ion transition route. In this method, ZnS ...A novel metal-free bulk nanocatalyst, S--N-codoped hollow carbon nanosphere/ graphene aerogel （SNC-GA-1000）, has been successfully fabricated using a facile and clean solid ion transition route. In this method, ZnS is used as the hard template and S source, while polydopamine acts as a reducing agent and carbon source. At a high annealing temperature, Zn metal is reduced and evaporates, leaving only free S vapor to diffuse into the carbon layer. Interestingly, the as-obtained SNC-GA-1000 exhibits much higher catalytic activity in an organic reduction reaction than unloaded bare S--N-codoped carbon nanospheres. Hydrothermal reduction of the graphene oxide sheets loaded with ZnSC@olydopamine core-shell nanospheres （ZnS@PDA） affords a three-dimensional bulk graphene aerogel. Although nanosized catalysts exhibit high catalytic activities, their subsequent separation is not always satisfactory, making post-treatment difficult. This approach achieves a trade-off between activity and separability. More importantly, due to the 3D structural nature, such bulk and handheld nanocatalysts can be easily separated and recycled.展开更多
文摘This study used a Polyindole in combination with TiO2 nanocatalyst as an efficient heterogeneous catalyst to carry out a multi-component Hantzsch reaction involving different aromatic aldehydes with methyl acetoacetate, and aqueous ammonium to create 1,4-dihydropyridine derivatives under solvent free condition at ambient temperature. A broad range of aldehydes and methyl acetoacetates, ranging from heteroaromatic to polyaromatic one, with high level of functional group tolerance can be used to provide the desired products possessing relevant medicinal moiety in high yields. This technology has prospective advantages over current protocols, including the utilization of a cheap, stable, recyclable, and safe catalyst, quicker reaction times with higher yields and simple product isolation.
基金University of TehranImam Hosseign University for supporting this work
文摘A simple and practical ultrasonically synthetic strategy for the preparation of rare-earth based catalyst, nanostructured NiFe2-xEuxO4 was developed. The structtre of NiFe2-xEuxO4 was characterized by various analyses such as X-ray diffraction （XRD）, scanning electron microscopy （SEM） and fourier transform infrared spectroscopy （FT-IR）. The catalytic performance of NiFe2-xEuxO4 was evaluated for the synthesis of benzimidazoles, benzoxazoles and benzothiazoles under ultrasonic irradiation. All reactions were completed in short times and all products were obtained in good to excellent yields in presence of the rare-earth based catalyst. Besides, NiFe2-xEuxO4 could be recovered for 6 times without noticeably decreasing the catalytic activity.
文摘A general method is developed to prepare durable hybrid nanocatalysts by nanostructuring the surface of gold wires via simple alloying and dealloying. The resulting nanoporous gold/Au （NPG/Au） wire catalysts possess nanoporous skins with their thicknesses on robust metal wires specified in a highly controllable manner. As a demonstration, the as-obtained NPG/Au was shown to be a highly active, chemo-selective, and recyclable catalyst for the reduction of nitro com- pounds and azides using organosilanes as reducing agents.
文摘Recent developments in nanochemistry offer precise morphology control of nanomaterials, which has significant impacts in the field of heterogeneous catalysis. Rational design of bifunctional catalysts can influence various aspects of catalytic properties. In this review, a new class of bifunctional catalysts with a metal@silica yolk-shell nanostructure is introduced. This structure has many advantages as a heterogeneous catalyst since it ensures a homogeneous environment around each metal core, and particle sintering is effectively eliminated during high temperature reactions. The catalysts exhibit high activity and recyclability in gas- and solution-phase reactions. It is anticipated that appropriate selection of bifunctional components and optimal structural control will significantly further enhance the catalytic properties, and enable target reaction-oriented development of new catalysts.
基金financially supported by the China special Science and Technology project on treatment and control of water pollution(No.2017ZX07402002)
文摘With the continuous development of nanomaterials in recent years,the application of nanocatalysts in catalytic ozone oxidation has attracted more and more researchers’attention due to their excellent catalytic properties.In this review,we systematically summarized the current research status of nanocatalysts mainly involving material categories,mechanisms and catalytic efficiency.Based on summary and analysis,we found most of the reported nanocatalysts were in the stage of laboratory research,which was caused by the nanocatalysts defects such as easy aggregation,difficult separation,and easy leakage.These defects might result in severe resource waste,economic loss and potentially adverse effects imposed on the ecosystem and human health.Aiming at solving these defects,we further analyzed the reasons and the existing reports,and revealed that coupling nano-catalyst and membrane,supported nanocatalysts and magnetic nanocatalysts had promising potential in solving these problems and promoting the actual application of nanocatalysts in wastewater treatment.Furthermore,the advantages,shortages and our perspectives of these methods are summarized and discussed.
基金This work was supported by the National Natural Science Foundation of China(21073184,21273231,and 21233008)Hundred Talents Program of the Chinese Academy of Sciences~~
基金The Vietnam National Foundation for Science and Technology Development(NAFOSTED)and the National Research Foundation of Korea(NRF)grant funded by the Korean government(MSIT)(Grant No.NRF-2022R1A2C1012996)。
文摘Environmental pollution,such as water contamination,is a critical issue that must be absolutely addressed.Here,three different morphologies of tungsten-based photocatalysts(WO_(3)nanorods,WO_(3)/WS_(2)nanobricks,WO_(3)/WS_(2)nanorods)are made using a simple hydrothermal method by changing the solvents(H_(2)O,DMF,aqueous HCl solution).The as-prepared nanocatalysts have excellent thermal stability,large porosity,and high hydrophilicity.The results show all materials have good photocatalytic activity in aqueous media,with WO_(3)/WS_(2)nanorods(NRs)having the best activity in the photodegradation of bisphenol A(BPA)under visible-light irradiation.This may originate from increased migration of charge carriers and effective prevention of electron–hole recombination in WO_(3)/WS_(2)NRs,whereby this photocatalyst is able to generate more reactive·OH and·O_(2)^(–)species,leading to greater photocatalytic activity.About 99.6% of BPA is photodegraded within 60 min when using 1.5 g/L WO_(3)/WS_(2)NRs and 5.0 mg/L BPA at pH 7.0.Additionally,the optimal conditions(pH,catalyst dosage,initial BPA concentration)for WO_(3)/WS_(2)NRs are also elaborately investigated.These rod-like heterostructures are expressed as potential catalysts with excellent photostability,efficient reusability,and highly active effectivity in different types of water.In particular,the removal efficiency of BPA by WO_(3)/WS_(2)NRs reduces by only 1.5% after five recycling runs and even reaches 89.1%in contaminated lake water.This study provides promising insights for the nearly complete removal of BPA from wastewater or different water resources,which is advantageous to various applications in environmental remediation.
基金supported by the National Natural Science Foundation of China (51374004,51204083)the Candidate Talents Training Fund of Yun-nan Province (2012HB009,2014HB006)+2 种基金the Applied Basic Research Program of Yunnan Province (2014FB123)a School-Enterprise Cooperation Project from Jinchuan Corporation (Jinchuan 201115)the Talents Training Program of Kunming University of Science and Technology (KKZ3201352038)~~
文摘This study focuses on drawing a hydrothermal synthesis process map for Co3O4 nanoparticles with various morphologies and investigating the effects of Co3O4 nanocatalyst morphology on CO oxidation.A series of cobalt-hydroxide-carbonate nanoparticles with various morphologies（i.e.,nanorods,nanosheets,and nanocubes） were successfully synthesized,and Co3O4 nanoparticles were obtained by thermal decomposition of the cobalt-hydroxide-carbonate precursors.The results suggest that the cobalt source is a key factor for controlling the morphology of cobalt-hydroxide-carbonate at relatively low hydrothermal temperatures（≤ 140℃）.Nanorods can be synthesized in CoCl2 solution,while Co（NO3）2 solution promotes the formation of nanosheets.Further increasing the synthesis temperature（higher than 140 ℃） results in the formation of nanocubes in either Co（NO3）2 or CoCl2 solution.The reaction time only affects the size of the obtained nanoparticles.The presence of CTAB could improve the uniformity and dispersion of particles.Co3O4 nanosheets showed much higher catalytic activity for CO oxidation than nanorods and nanocubes because it has more abundant Co^（3＋） on the surface,much higher reducibility,and better oxygen desorption capacity.
基金the Faculty of Chemistry of Semnan University for supporting this work
文摘Nano titania-supported sulfonic acid（n-TSA） has found to be a highly efficient, eco-friendly and recyclable heterogeneous nanocatalyst for the solvent-free synthesis of 2,4,6-triarylpyridines through one-pot three-component reaction of acetophenones, aryl aldehydes and ammonium acetate. This reported method illustrates several advantages such as environmental friendliness reaction conditions,simplicity, short reaction time, easy work up, reusability of catalyst and high yields of the products. One new compound is reported too. Furthermore, the catalyst could be recycled after a simple work-up, and reused at least six times without substantial reduction in its catalytic activity.
基金supported by the National Key R&D Program of China(2017YFA0206802)the National Natural Science Foundation of China(91545201,91645116,21403237)the Chinese Academy of Sciences(XDB20010100,ZDRW-CN-2016-1,QYZDJSSW-SLH028)
文摘Methyl formate is one of the most important intermediates in C1 chemistry, which has been employed in a wide range of industrial applications. Current synthesis methods for methyl formate mainly include esterification of methanol and formic acid, liquid-phase methanol carbonylation, oxidative dehydrogenation of methanol, one-step syngas synthesis, and carbon dioxide hydrogenation and condensation with methanol, Liquid-phase methanol carbonylation is currently a main commercially viable process devel- oped by BASF Corp, for the industrial production of methyl formate. Recently, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences has developed a new synthesis method to con- vert coal to methyl formate （denoted as CTMF）, Different from the liquid-phase methanol carbonylation using homogeneous catalysts, CTMF method features with vapor-phase methanol carbonylation using het- erogeneous nanocatalysts, which can effectively utilize the coal-based syngas and produce value-added fine chemicals （i.e., methyl formate）. The newly developed method not only provides a new methyl for- mate synthesis technology but also contributes to the development of strategies for synthesizing valuable chemicals from coal. In this review, we firstly provide introduction on the development of existing methyl formate synthesis methods and then highlight the research progress of CTMF method. Finally, a perspec- tive on the future of CTMF is given,
基金Acknowledgements The authors are grateful for the financial aid from the National Natural Science Foundation of China （Nos. 51372242, 21590794, 21210001, and 21521092）, Hong Kong, Macao and Taiwan Science and Technology Cooperation Special Project of Ministry of Science and Technology of China （No. 2014DFT10310）, the National Key Basic Research Program of China （No. 2014CB643802）, Youth Innovation Promotion Association of Chinese Academy of Sciences （No. 2011176）, CAS- CSIRO project （No. GJHZ1730） and the Program of Science and Technology Development Plan of Jilin Province of China （No. 20140201007GX）.
文摘A novel metal-free bulk nanocatalyst, S--N-codoped hollow carbon nanosphere/ graphene aerogel （SNC-GA-1000）, has been successfully fabricated using a facile and clean solid ion transition route. In this method, ZnS is used as the hard template and S source, while polydopamine acts as a reducing agent and carbon source. At a high annealing temperature, Zn metal is reduced and evaporates, leaving only free S vapor to diffuse into the carbon layer. Interestingly, the as-obtained SNC-GA-1000 exhibits much higher catalytic activity in an organic reduction reaction than unloaded bare S--N-codoped carbon nanospheres. Hydrothermal reduction of the graphene oxide sheets loaded with ZnSC@olydopamine core-shell nanospheres （ZnS@PDA） affords a three-dimensional bulk graphene aerogel. Although nanosized catalysts exhibit high catalytic activities, their subsequent separation is not always satisfactory, making post-treatment difficult. This approach achieves a trade-off between activity and separability. More importantly, due to the 3D structural nature, such bulk and handheld nanocatalysts can be easily separated and recycled.
