Due to the high capacity and moderate volume expansion of silicon protoxide SiO_(x)(160%)compared with that of Si(300%),reducing silicon dioxide SiO_(2)into SiO_(x)while maintaining its special nano-morphology makes i...Due to the high capacity and moderate volume expansion of silicon protoxide SiO_(x)(160%)compared with that of Si(300%),reducing silicon dioxide SiO_(2)into SiO_(x)while maintaining its special nano-morphology makes it attractive as an anode of Li-ion batteries.Herein,through a one-pot facile high-temperature annealing route,using SBA15 as the silicon source,and embedding tin dioxide SnO_(2)particles into carbon coated SiO_(x),the mesoporous SiO_(x)-SnO_(2)@C rod composite was prepared and tested as the anode material.The results revealed that the SnO_(2)particles were distributed uniformly in the wall,which could further improve their volume energy densities.The coated carbon plays a role in maintaining structural integrality during lithiation,and the rich mesopores structure can release the expanded volume and enhance Li-ion transfer.At 0.1 A·g^(-1),the gravimetric and volumetric capacities of the composite were as high as 1271 mAh·g^(-1)and 1573 mAh·cm^(-3),respectively.After 200 cycles,the 95%capacity could be retained compared with that upon the 2nd cycle at 0.5 A·g^(-1).And the rod morphology was well kept,except that the diameter of the rod was 3 times larger than its original size after the cell was discharged into 0.01 V.展开更多
Mesoporous carbon supports mitigate platinum(Pt)sulfonic poisoning through nanopore-confined Pt deposition,yet their morphological impacts on oxygen transport remain unclear.This study integrates carbon support morpho...Mesoporous carbon supports mitigate platinum(Pt)sulfonic poisoning through nanopore-confined Pt deposition,yet their morphological impacts on oxygen transport remain unclear.This study integrates carbon support morphology simulation with an enhanced agglomerate model to establish a mathematical framework elucidating pore evolution,Pt utilization,and oxygen transport in catalyst layers.Results demonstrate dominant local mass transport resistance governed by three factors:(1)active site density dictating oxygen flux;(2)ionomer film thickness defining shortest transport path;(3)ionomer-to-Pt surface area ratio modulating practical pathway length.At low ionomer-to-carbon(I/C)ratios,limited active sites elevate resistance(Factor 1 dominant).Higher I/C ratios improve the ionomer coverage but eventually thicken ionomer films,degrading transport(Factors 2–3 dominant).The results indicate that larger carbon particles result in a net increase in local transport resistance by reducing external surface area and increasing ionomer thickness.As the proportion of Pt situated in nanopores or the Pt mass fraction increases,elevated Pt density inside the nanopores exacerbates pore blockage.This leads to the increased transport resistance by reducing active sites,and increasing ionomer thickness and surface area.Lower Pt loading linearly intensifies oxygen flux resistance.The model underscores the necessity to optimize support morphology,Pt distribution,and ionomer content to prevent pore blockage while balancing catalytic activity and transport efficiency.These insights provide a systematic approach for designing high-performance mesoporous carbon catalysts.展开更多
Three-dimensional ordered macro/mesoporous carbon(3DOM/m-C)with high specific surface area was synthesized by colloid crystal template method with chemical activation by KOH and used as the adsorbent for removing mala...Three-dimensional ordered macro/mesoporous carbon(3DOM/m-C)with high specific surface area was synthesized by colloid crystal template method with chemical activation by KOH and used as the adsorbent for removing malachite green(MG)in aqueous solution.The microstructures of the adsorbents were characterized by FESEM,TEM and BET,and the effects of initial dye concentration,contact time,solution pH,and temperature on adsorption performance were investigated.The results show that the 3DOM/m-C exhibits extremely high adsorption capacity of 3541.1 mg/g within 2 h,which could be attributed to the novel ordered hierarchical structure with mesopores on three-dimensional ordered macroporous carbon walls.And the adsorption behavior conforms to the pseudo-second-order kinetic and Langmuir adsorption isotherm.3DOM/m-C can be recycled after being desorbed by absolute ethanol,and still maintains a high capacity of 2762.06 mg/g after 5 cycles.展开更多
The pore structures and electrochemical performances of mesoporous carbons prepared by silica sol template method as electrode material for supercapacitor were investigated. The mean pore size and mass specific capaci...The pore structures and electrochemical performances of mesoporous carbons prepared by silica sol template method as electrode material for supercapacitor were investigated. The mean pore size and mass specific capacitance of the mesoporous carbons increase with the increase of mass ratio of silica sol to carbon source （glucose）. A modified template method, combining silica sol template method and ZnCl2 chemical activation method, was proposed to improve the mass specific capacitance of the mesoporous carbon with an improved BET surface area. The correlation of rate capability and pore structure was studied by constant current discharge and electrochemical impedance spectroscopy. A commercially available microporous carbon was used for comparison. The result shows that mesoporous carbon with a larger pore size displays a higher rate capability. Mesoporous carbon synthesized by modified template method has both high mass specific capacitance and good rate capability.展开更多
Mesoporous CeO2 was first synthesized by hydrothermal method,and then used to synthesize different contents of CuO)x/CeO2(x:molar ratio of Cu to Ce) by deposition-precipitation method.These materials were characterize...Mesoporous CeO2 was first synthesized by hydrothermal method,and then used to synthesize different contents of CuO)x/CeO2(x:molar ratio of Cu to Ce) by deposition-precipitation method.These materials were characterized by X-ray diffraction(XRD),N2 adsorption and desorption,H2 temperature programmed reduction(H2-TPR) and O2 temperature programmed desorption(O2-TPD) to study the crystal structure,surface area,and the mechanism of CO oxidation.The results show that,on XRD patterns,no evidence of CuO diffraction peaks is present until Cu loading is increased to 20%.The BET surface area decreases noticeably with the increase of Cu content.Compared with other samples,the better reducibility and activity oxygen species of(CuO)10%/CeO2coincide with its better catalytic activity.展开更多
The mesoporous Ti O2 has been synthesized by evaporation induced self assembly(EISA) method. The thermogravimetric/differential scanning calorimetric(TG/DSC), X-ray diffraction(XRD), high-resolution transmission elect...The mesoporous Ti O2 has been synthesized by evaporation induced self assembly(EISA) method. The thermogravimetric/differential scanning calorimetric(TG/DSC), X-ray diffraction(XRD), high-resolution transmission electron microscopy(HR-TEM) and N2 adsorption desorption and adsorption are used to study the effects of the synthesized process condition on the microstructure of the as-synthesized mesoporous Ti O2. The photocatalytic performances of as-synthesized samples are evaluated by the degradation of the formaldehyde under ultraviolet light irradiations. The results demonstrate that the as-synthesized mesoporous Ti O2 are anatase with the uniform size about 20-40 nm. The sample is prepared using cetyltrimethyl ammonium bromide(CTAB) as the template with average pore size distribution of 8.12 nm, specific surface area of 68.47 m2/g and pore volume of 0.213 m L/g. The samples show decomposition of formaldehyde 95.8% under ultraviolet light irradiations for 90 min. These results provide a basic experimental process for preparation mesoporous Ti O2, which will posses a broad prospect in terms of the applications in improving indoor air quality.展开更多
Mesoporous molecular sieve with Al-promoted sulfated rirconia (SZA) based strong solid acid nano-particles within its mesoporous channels was synthesized by using a one-step incipient wetness impregnation method with ...Mesoporous molecular sieve with Al-promoted sulfated rirconia (SZA) based strong solid acid nano-particles within its mesoporous channels was synthesized by using a one-step incipient wetness impregnation method with zirconium sulfate and aluminum sulfate as the precursors. The assemblies of SZA/MCM-41 were obtained by thermal decomposition of the precursors in air.The resultant composite was characterized with various techniques such as nitrogen physisorption, X-ray diffraction, SEM and TEM. It was shown that the well-ordered channels of MCM-41 arranged in hexagonal arrays as well as the hollow tubular morphology was retained. The strong solid acid nanoparticles were isolated born each other and highly, dispersed in the channels. Nitrogen sorption showed the expected decrease in pore volume. The catalytic activity of SZA/MCM-41 composite in the isomerization of n-butane was dramatically improved in comparison to bulk SZA or SZA/silica.展开更多
A light and temperature dual responsive copolymer,poly(7-(4-vinylbenzy-loxyl)-4-methylcoumarin-co-N vinyl caprolactam-co-tri(ethylene glycol)methyl ether methacrylate)(PVNM),was grafted on the surface of dopamine base...A light and temperature dual responsive copolymer,poly(7-(4-vinylbenzy-loxyl)-4-methylcoumarin-co-N vinyl caprolactam-co-tri(ethylene glycol)methyl ether methacrylate)(PVNM),was grafted on the surface of dopamine based mesoporous silica nanoparticles(MSNs).The resulting polymer brush,MSNs-g-PVNM,was characterized by FT-IR,TEM,TGA and XPS.The dual responsive behaviors of MSNs-g-PVNM were systematically studied.With imidacloprid as the model guest pesticide,the loading percentage and loading efficiency of the polymer brush were determined as 9.2%and 40.6%,respectively.The release efficiency of imidacloprid in MSNs-g-PVNM was the lowest value of 5.4%at 20℃ and 365 nm,and it reached the highest value of 52.4%at 50℃ and 254 nm.The loss percentage of imidacloprid on the leaves contained imidacloprid-loaded MSNs-g-PVNM(8.4%)was much less than that contained only imidacloprid(25.2%)after three rinses.It was confirmed that the release process of imidacloprid was well regulated through changing external conditions such as light and temperature.展开更多
The toxic effects to microorganism induced by nanomaterials have received considerable attentions in the past decades [1]. Herein, two diverse nanomaterials i.e. multi-walled carbon nanotubes (MWCNTs) and mesoporous s...The toxic effects to microorganism induced by nanomaterials have received considerable attentions in the past decades [1]. Herein, two diverse nanomaterials i.e. multi-walled carbon nanotubes (MWCNTs) and mesoporous silica nanospheres (MSNs) were prepared to investigate their deleterious effects on Caenorhabditis. elegans (C. elegans)[2-3]. As shown in Figure 1A, histidine functionalized MWCNTs (his-MWCNTs) were in length of ~500 nm with outer diameter ~20 nm, while fluorescein isothiocyanate dyed MSNs (FITC-MSNs) were in an average diameter of ~70 nm (Figure 1B). Microscopic images display his-MWCNTs having been ingested into intestine of C. elegans after co-incubation for 2 h, as arrowed in Figure 1C and 1E. In contrast, no MSNs were observed to be ingested after co-incubating in the same liquid medium. However, fluorescence microscopic images (Figure 1D and 1F) demonstrate that FITC-MSNs could be ingested by C. elegans after co-incubation for 24 h or longer time via seeding Kingagar plates with FITC-MSNs.展开更多
The template carbonization method was utilized for the production of mesoporous carbons using attapulgite as a template and sucrose as carbon precursor. Sucrose was polymerized and carbonized in the tubes of natural a...The template carbonization method was utilized for the production of mesoporous carbons using attapulgite as a template and sucrose as carbon precursor. Sucrose was polymerized and carbonized in the tubes of natural attapulgite using a sulfuric acid catalyst. The structure of the template and carbons were investigated by powder X-ray diffraction, transmission electron microscopy, and Nitrogen adsorption analysis techniques. At the micrometer level, the carbon material templated with the natural attapulgite had the similar morphology. Nitrogen adsorption analysis showed that the obtained porous carbons possess a wide pore size distribution and a large pore volume, especially in the range of mesopores.展开更多
Mesoporous cerium-zirconium mixed oxides were prepared by hydrothermal method using cetyl trimethyl ammonium bromide (CTAB) as template. The effects of amount of template, pH value of solution and hydrothermal tempera...Mesoporous cerium-zirconium mixed oxides were prepared by hydrothermal method using cetyl trimethyl ammonium bromide (CTAB) as template. The effects of amount of template, pH value of solution and hydrothermal temperature on mesostructure of samples were systematically investigated. The final products were characterized by XRD, TEM, FT-IR, and BET. The results indicate that all the cerium-zirconium mixed oxides present a meso-structure. At molar ratio of n(CTAB)/n((Ce)+(Zr))= 0.15, pH value of 9, and hydrothermal temperature of 120 ℃, the samples obtained possess a specific surface area of 207.9 m2/g with pore diameter of 3.70 nm and pore volume of 0.19 cm3/g.展开更多
SnO_(2)is used as electrode material with excellent properties,but it has some disadvantages such as slow reaction kinetics,low inherent conductivity and complex preparation process.Here,SnO_(2)@carbon nanotubes(SnO_(...SnO_(2)is used as electrode material with excellent properties,but it has some disadvantages such as slow reaction kinetics,low inherent conductivity and complex preparation process.Here,SnO_(2)@carbon nanotubes(SnO_(2)@CNTs)is synthesized through an efficient method of one-pot alternating current electrochemical dispersion.By using heat treatment at 400℃,the SnO_(2)@CNTs-400 composite material with abundant mesoporous structure is obtained,while the crystal particles are grown,and a strong bonding effect is formed with CNTs via powerful Sn-O-C bond.Benefiting from the introduction of high electrical conductivity CNTs and outstanding structural characteristics,as prepared composite material(SnO_(2)@CNTs-400)exhibit enhanced diffusion dynamics,lithium-ion transmission rate and structural steadiness.The specific capacity of SnO_(2)@CNTs and SnO_(2)@CNTs-400 as anodes for lithium-ion batteries can reach 690.2 mA·h/g and 836.5 mA·h/g,respectively,after 100 cycles at 0.5 A/g.The abundant chemical bonds and porous structure can be formed in composite via alternating current synthesis method,which takes significant in improving electrochemical properties.展开更多
Perovskite solar cells(PSCs) have emerged as one of the most promising candidates for photovoltaic applications. Low-cost, low-temperature solution processes including coating and printing techniques makes PSCs promis...Perovskite solar cells(PSCs) have emerged as one of the most promising candidates for photovoltaic applications. Low-cost, low-temperature solution processes including coating and printing techniques makes PSCs promising for the greatly potential commercialization due to the scalability and compatibility with large-scale, roll-to-roll manufacturing processes. In this review, we focus on the solution deposition of charge transport layers and perovskite absorption layer in both mesoporous and planar structural PSC devices. Furthermore, the most recent design strategies via solution deposition are presented as well, which have been explored to enlarge the active area, enhance the crystallization and passivate the defects, leading to the performance improvement of PSC devices.展开更多
The ternary catalyst Pt75Ru5Ni20 was conducted on various types of carbon supports including functionalized Vulcan XC-72R(f-CB),functionalized multi-walled carbon nanotubes(f-MWCNT),and mesoporous carbon(PC-Zn-succini...The ternary catalyst Pt75Ru5Ni20 was conducted on various types of carbon supports including functionalized Vulcan XC-72R(f-CB),functionalized multi-walled carbon nanotubes(f-MWCNT),and mesoporous carbon(PC-Zn-succinic)by sodium borohydride chemical reduction method to improve the ethanol electrooxidation reaction(EOR)for direct ethanol fuel cell(DEFC).It was found that the particle size of the metals on f-MWCNT was 5.20 nm with good particle dispersion.The alloy formation of ternary catalyst was confirmed by XRD and more clearly described by SEM element mapping,which was relevant to the efficiency of the catalysts.Moreover,the mechanism of ethanol electrooxidation reaction based on the surface reaction was more understanding.The activity and stability for ethanol electrooxidation reaction(EOR)were investigated using cyclic voltammetry and chronoamperometry,respectively.The highest activity and stability for EOR were observed from Pt75Ru5Ni20/f-MWCNT due to a good metal-carbon interaction.Ru and Ni presented in Pt-Ru-Ni alloy improved the activity and stability of ternary catalysts for EOR.Moreover,the reduction of Pt content in ternary catalyst led to the catalyst cost deduction in DEFC.展开更多
A high-performance porous carbon material for supercapacitor electrodes was prepared by using a polymer blend method. Phenol-formaldehyde resin and gelatin were used as carbon precursor polymer and pore former polymer...A high-performance porous carbon material for supercapacitor electrodes was prepared by using a polymer blend method. Phenol-formaldehyde resin and gelatin were used as carbon precursor polymer and pore former polymer, respectively. The blends were carbonized at 800℃ in nitrogen. SEM, BET measurement and BJH method reveal that the obtained carbon possesses a mesoporous characteristic, with the average pore size between 3.0 nm and 5.0 nm. The electrochemical properties of supercapacitor using these carbons as electrode material were investigated by cyclic voltammetry and constant current charge-discharge. The results indicate that the composition of blended polymers has a strong effect on the specific capacitance. When the mass ratio of PF to gelatin is kept at 1：1, the largest surface area of 222 m2/g is obtained, and the specific capacitance reaches 161 F/g.展开更多
文摘Due to the high capacity and moderate volume expansion of silicon protoxide SiO_(x)(160%)compared with that of Si(300%),reducing silicon dioxide SiO_(2)into SiO_(x)while maintaining its special nano-morphology makes it attractive as an anode of Li-ion batteries.Herein,through a one-pot facile high-temperature annealing route,using SBA15 as the silicon source,and embedding tin dioxide SnO_(2)particles into carbon coated SiO_(x),the mesoporous SiO_(x)-SnO_(2)@C rod composite was prepared and tested as the anode material.The results revealed that the SnO_(2)particles were distributed uniformly in the wall,which could further improve their volume energy densities.The coated carbon plays a role in maintaining structural integrality during lithiation,and the rich mesopores structure can release the expanded volume and enhance Li-ion transfer.At 0.1 A·g^(-1),the gravimetric and volumetric capacities of the composite were as high as 1271 mAh·g^(-1)and 1573 mAh·cm^(-3),respectively.After 200 cycles,the 95%capacity could be retained compared with that upon the 2nd cycle at 0.5 A·g^(-1).And the rod morphology was well kept,except that the diameter of the rod was 3 times larger than its original size after the cell was discharged into 0.01 V.
基金supported by the Program of Ministry of Science and Technology of China(No.2023YFB2504200)support of Shanghai Rising-Star Program(Grant No.24QB2703200)the Major Science and Technology Projects of Yunnan Province(No.202302AH360001).
文摘Mesoporous carbon supports mitigate platinum(Pt)sulfonic poisoning through nanopore-confined Pt deposition,yet their morphological impacts on oxygen transport remain unclear.This study integrates carbon support morphology simulation with an enhanced agglomerate model to establish a mathematical framework elucidating pore evolution,Pt utilization,and oxygen transport in catalyst layers.Results demonstrate dominant local mass transport resistance governed by three factors:(1)active site density dictating oxygen flux;(2)ionomer film thickness defining shortest transport path;(3)ionomer-to-Pt surface area ratio modulating practical pathway length.At low ionomer-to-carbon(I/C)ratios,limited active sites elevate resistance(Factor 1 dominant).Higher I/C ratios improve the ionomer coverage but eventually thicken ionomer films,degrading transport(Factors 2–3 dominant).The results indicate that larger carbon particles result in a net increase in local transport resistance by reducing external surface area and increasing ionomer thickness.As the proportion of Pt situated in nanopores or the Pt mass fraction increases,elevated Pt density inside the nanopores exacerbates pore blockage.This leads to the increased transport resistance by reducing active sites,and increasing ionomer thickness and surface area.Lower Pt loading linearly intensifies oxygen flux resistance.The model underscores the necessity to optimize support morphology,Pt distribution,and ionomer content to prevent pore blockage while balancing catalytic activity and transport efficiency.These insights provide a systematic approach for designing high-performance mesoporous carbon catalysts.
基金Projects(U1802254,51871201)supported by the National Natural Science Foundation of ChinaProject(LY18E040003)supported by the Zhejiang Provincial Natural Science Foundation,China
文摘Three-dimensional ordered macro/mesoporous carbon(3DOM/m-C)with high specific surface area was synthesized by colloid crystal template method with chemical activation by KOH and used as the adsorbent for removing malachite green(MG)in aqueous solution.The microstructures of the adsorbents were characterized by FESEM,TEM and BET,and the effects of initial dye concentration,contact time,solution pH,and temperature on adsorption performance were investigated.The results show that the 3DOM/m-C exhibits extremely high adsorption capacity of 3541.1 mg/g within 2 h,which could be attributed to the novel ordered hierarchical structure with mesopores on three-dimensional ordered macroporous carbon walls.And the adsorption behavior conforms to the pseudo-second-order kinetic and Langmuir adsorption isotherm.3DOM/m-C can be recycled after being desorbed by absolute ethanol,and still maintains a high capacity of 2762.06 mg/g after 5 cycles.
文摘The pore structures and electrochemical performances of mesoporous carbons prepared by silica sol template method as electrode material for supercapacitor were investigated. The mean pore size and mass specific capacitance of the mesoporous carbons increase with the increase of mass ratio of silica sol to carbon source （glucose）. A modified template method, combining silica sol template method and ZnCl2 chemical activation method, was proposed to improve the mass specific capacitance of the mesoporous carbon with an improved BET surface area. The correlation of rate capability and pore structure was studied by constant current discharge and electrochemical impedance spectroscopy. A commercially available microporous carbon was used for comparison. The result shows that mesoporous carbon with a larger pore size displays a higher rate capability. Mesoporous carbon synthesized by modified template method has both high mass specific capacitance and good rate capability.
基金Project(2011FZ030)supported by the Natural Science Foundation of Yunnan Province,ChinaProjects(2011144,2011221)supported by Analysis and Test Foundation of Kunming University of Science and Technology,China
文摘Mesoporous CeO2 was first synthesized by hydrothermal method,and then used to synthesize different contents of CuO)x/CeO2(x:molar ratio of Cu to Ce) by deposition-precipitation method.These materials were characterized by X-ray diffraction(XRD),N2 adsorption and desorption,H2 temperature programmed reduction(H2-TPR) and O2 temperature programmed desorption(O2-TPD) to study the crystal structure,surface area,and the mechanism of CO oxidation.The results show that,on XRD patterns,no evidence of CuO diffraction peaks is present until Cu loading is increased to 20%.The BET surface area decreases noticeably with the increase of Cu content.Compared with other samples,the better reducibility and activity oxygen species of(CuO)10%/CeO2coincide with its better catalytic activity.
基金Projects(51102026,51272032) supported by the Program for the National Natural Science Foundation of ChinaProject(11A014) supported by the Scientific Research Fund of Hunan Provincial Education DepartmentProject supported by the Aid Program for Science and Technology Innovative Research Team in Higher Educational Instituions of Hunan Province,China
文摘The mesoporous Ti O2 has been synthesized by evaporation induced self assembly(EISA) method. The thermogravimetric/differential scanning calorimetric(TG/DSC), X-ray diffraction(XRD), high-resolution transmission electron microscopy(HR-TEM) and N2 adsorption desorption and adsorption are used to study the effects of the synthesized process condition on the microstructure of the as-synthesized mesoporous Ti O2. The photocatalytic performances of as-synthesized samples are evaluated by the degradation of the formaldehyde under ultraviolet light irradiations. The results demonstrate that the as-synthesized mesoporous Ti O2 are anatase with the uniform size about 20-40 nm. The sample is prepared using cetyltrimethyl ammonium bromide(CTAB) as the template with average pore size distribution of 8.12 nm, specific surface area of 68.47 m2/g and pore volume of 0.213 m L/g. The samples show decomposition of formaldehyde 95.8% under ultraviolet light irradiations for 90 min. These results provide a basic experimental process for preparation mesoporous Ti O2, which will posses a broad prospect in terms of the applications in improving indoor air quality.
文摘Mesoporous molecular sieve with Al-promoted sulfated rirconia (SZA) based strong solid acid nano-particles within its mesoporous channels was synthesized by using a one-step incipient wetness impregnation method with zirconium sulfate and aluminum sulfate as the precursors. The assemblies of SZA/MCM-41 were obtained by thermal decomposition of the precursors in air.The resultant composite was characterized with various techniques such as nitrogen physisorption, X-ray diffraction, SEM and TEM. It was shown that the well-ordered channels of MCM-41 arranged in hexagonal arrays as well as the hollow tubular morphology was retained. The strong solid acid nanoparticles were isolated born each other and highly, dispersed in the channels. Nitrogen sorption showed the expected decrease in pore volume. The catalytic activity of SZA/MCM-41 composite in the isomerization of n-butane was dramatically improved in comparison to bulk SZA or SZA/silica.
基金Project(21376271)supported by the National Natural Science Foundation of ChinaProject(2016TP1007)supported by the Hunan Provincial Science and Technology Plan Project,ChinaProjects(201810533078,S2020105330395)supported by the Undergraduates Innovative Training Foundation of Central South University,China。
文摘A light and temperature dual responsive copolymer,poly(7-(4-vinylbenzy-loxyl)-4-methylcoumarin-co-N vinyl caprolactam-co-tri(ethylene glycol)methyl ether methacrylate)(PVNM),was grafted on the surface of dopamine based mesoporous silica nanoparticles(MSNs).The resulting polymer brush,MSNs-g-PVNM,was characterized by FT-IR,TEM,TGA and XPS.The dual responsive behaviors of MSNs-g-PVNM were systematically studied.With imidacloprid as the model guest pesticide,the loading percentage and loading efficiency of the polymer brush were determined as 9.2%and 40.6%,respectively.The release efficiency of imidacloprid in MSNs-g-PVNM was the lowest value of 5.4%at 20℃ and 365 nm,and it reached the highest value of 52.4%at 50℃ and 254 nm.The loss percentage of imidacloprid on the leaves contained imidacloprid-loaded MSNs-g-PVNM(8.4%)was much less than that contained only imidacloprid(25.2%)after three rinses.It was confirmed that the release process of imidacloprid was well regulated through changing external conditions such as light and temperature.
文摘The toxic effects to microorganism induced by nanomaterials have received considerable attentions in the past decades [1]. Herein, two diverse nanomaterials i.e. multi-walled carbon nanotubes (MWCNTs) and mesoporous silica nanospheres (MSNs) were prepared to investigate their deleterious effects on Caenorhabditis. elegans (C. elegans)[2-3]. As shown in Figure 1A, histidine functionalized MWCNTs (his-MWCNTs) were in length of ~500 nm with outer diameter ~20 nm, while fluorescein isothiocyanate dyed MSNs (FITC-MSNs) were in an average diameter of ~70 nm (Figure 1B). Microscopic images display his-MWCNTs having been ingested into intestine of C. elegans after co-incubation for 2 h, as arrowed in Figure 1C and 1E. In contrast, no MSNs were observed to be ingested after co-incubating in the same liquid medium. However, fluorescence microscopic images (Figure 1D and 1F) demonstrate that FITC-MSNs could be ingested by C. elegans after co-incubation for 24 h or longer time via seeding Kingagar plates with FITC-MSNs.
文摘The template carbonization method was utilized for the production of mesoporous carbons using attapulgite as a template and sucrose as carbon precursor. Sucrose was polymerized and carbonized in the tubes of natural attapulgite using a sulfuric acid catalyst. The structure of the template and carbons were investigated by powder X-ray diffraction, transmission electron microscopy, and Nitrogen adsorption analysis techniques. At the micrometer level, the carbon material templated with the natural attapulgite had the similar morphology. Nitrogen adsorption analysis showed that the obtained porous carbons possess a wide pore size distribution and a large pore volume, especially in the range of mesopores.
基金Project(CHCL0501) supported by Hubei Provincial Open Fund of Key Laboratory of Catalytic Material Science and Technology
文摘Mesoporous cerium-zirconium mixed oxides were prepared by hydrothermal method using cetyl trimethyl ammonium bromide (CTAB) as template. The effects of amount of template, pH value of solution and hydrothermal temperature on mesostructure of samples were systematically investigated. The final products were characterized by XRD, TEM, FT-IR, and BET. The results indicate that all the cerium-zirconium mixed oxides present a meso-structure. At molar ratio of n(CTAB)/n((Ce)+(Zr))= 0.15, pH value of 9, and hydrothermal temperature of 120 ℃, the samples obtained possess a specific surface area of 207.9 m2/g with pore diameter of 3.70 nm and pore volume of 0.19 cm3/g.
基金Project(2023JЛ10041)supported by the Distinguished Young Scholar Fund Project of Hunan Province Natural Science Foundation,ChinaProject(22A0114)supported by the Hunan Provincial Education Office Foundation of China+2 种基金Projects(GX-ZD20211004,GX-ZD20221007)supported by the Science and Technology Program of Xiangtan,ChinaProject(R24-5979269037)supported by the RSC Research Fund Grout,EnglandProject(S202310530037X)supported by the National College Students Innovative Experimental Program Funding Project,China。
文摘SnO_(2)is used as electrode material with excellent properties,but it has some disadvantages such as slow reaction kinetics,low inherent conductivity and complex preparation process.Here,SnO_(2)@carbon nanotubes(SnO_(2)@CNTs)is synthesized through an efficient method of one-pot alternating current electrochemical dispersion.By using heat treatment at 400℃,the SnO_(2)@CNTs-400 composite material with abundant mesoporous structure is obtained,while the crystal particles are grown,and a strong bonding effect is formed with CNTs via powerful Sn-O-C bond.Benefiting from the introduction of high electrical conductivity CNTs and outstanding structural characteristics,as prepared composite material(SnO_(2)@CNTs-400)exhibit enhanced diffusion dynamics,lithium-ion transmission rate and structural steadiness.The specific capacity of SnO_(2)@CNTs and SnO_(2)@CNTs-400 as anodes for lithium-ion batteries can reach 690.2 mA·h/g and 836.5 mA·h/g,respectively,after 100 cycles at 0.5 A/g.The abundant chemical bonds and porous structure can be formed in composite via alternating current synthesis method,which takes significant in improving electrochemical properties.
基金Projects(51673214,51673218,61774170)supported by the National Natural Science Foundation of ChinaProject(2017YFA0206600)supported by the National Key Research and Development Program of China。
文摘Perovskite solar cells(PSCs) have emerged as one of the most promising candidates for photovoltaic applications. Low-cost, low-temperature solution processes including coating and printing techniques makes PSCs promising for the greatly potential commercialization due to the scalability and compatibility with large-scale, roll-to-roll manufacturing processes. In this review, we focus on the solution deposition of charge transport layers and perovskite absorption layer in both mesoporous and planar structural PSC devices. Furthermore, the most recent design strategies via solution deposition are presented as well, which have been explored to enlarge the active area, enhance the crystallization and passivate the defects, leading to the performance improvement of PSC devices.
基金supported by the Institutional Research Grant(Thailand Research Fund:IRG598004)
文摘The ternary catalyst Pt75Ru5Ni20 was conducted on various types of carbon supports including functionalized Vulcan XC-72R(f-CB),functionalized multi-walled carbon nanotubes(f-MWCNT),and mesoporous carbon(PC-Zn-succinic)by sodium borohydride chemical reduction method to improve the ethanol electrooxidation reaction(EOR)for direct ethanol fuel cell(DEFC).It was found that the particle size of the metals on f-MWCNT was 5.20 nm with good particle dispersion.The alloy formation of ternary catalyst was confirmed by XRD and more clearly described by SEM element mapping,which was relevant to the efficiency of the catalysts.Moreover,the mechanism of ethanol electrooxidation reaction based on the surface reaction was more understanding.The activity and stability for ethanol electrooxidation reaction(EOR)were investigated using cyclic voltammetry and chronoamperometry,respectively.The highest activity and stability for EOR were observed from Pt75Ru5Ni20/f-MWCNT due to a good metal-carbon interaction.Ru and Ni presented in Pt-Ru-Ni alloy improved the activity and stability of ternary catalysts for EOR.Moreover,the reduction of Pt content in ternary catalyst led to the catalyst cost deduction in DEFC.
基金Projects(50772033,50972043) supported by the National Natural Science Foundation of ChinaProject(09JJ3095) supported by the Natural Science Foundation of Hunan Province,China+2 种基金Project(09A001) supported by the Scientific Research Fund of Hunan Provincial Education Department,ChinaProject(2010FJ3151) supported by the Science and Research Plan of Hunan Province,ChinaProject supported by the Science and Technology Innovative Research Team in Higher Education Institution of Hunan Province,China
文摘A high-performance porous carbon material for supercapacitor electrodes was prepared by using a polymer blend method. Phenol-formaldehyde resin and gelatin were used as carbon precursor polymer and pore former polymer, respectively. The blends were carbonized at 800℃ in nitrogen. SEM, BET measurement and BJH method reveal that the obtained carbon possesses a mesoporous characteristic, with the average pore size between 3.0 nm and 5.0 nm. The electrochemical properties of supercapacitor using these carbons as electrode material were investigated by cyclic voltammetry and constant current charge-discharge. The results indicate that the composition of blended polymers has a strong effect on the specific capacitance. When the mass ratio of PF to gelatin is kept at 1：1, the largest surface area of 222 m2/g is obtained, and the specific capacitance reaches 161 F/g.
