Though flexible electrochromic devices have shown huge potential application in the fields of safety warning,display and smart windows,limited attention was paid on preparing flexible electrochromic fiber because of t...Though flexible electrochromic devices have shown huge potential application in the fields of safety warning,display and smart windows,limited attention was paid on preparing flexible electrochromic fiber because of the difficulty in fabricating the multilayer electrochromic device structure in one-dimensional form.In this study,a flexible electrochromic nylon fiber based on Ag nanowires(NWs)/PEDOT:PSS/WO3 nanoparticles(NPs)(PEDOT:PSS=poly(3,4-ethylenedioxythiophene):polystyrenesulfonic acid)is successfully fabricated,delivering rapid color switching(2.5 and 9 s for bleaching and coloration)and high optical modulation(65.5%at 633 nm),and sustainable to repeated mechanical deformations.Ag NWs,PEDOT:PSS and WO3 NPs were dip-coated on the nylon fiber,resulting in an electrochromic fiber electrode with stable fiber resistance of 50-100Ω/10 cm,which can withstand mechanical deformation against 300 times of bending cycles with bending radius of 0.5 cm,and sustain 30 times of tape-peeling.During the galvanostatic tests,the capacitance of the electrochromic electrode can maintain 70%of the initial value even after 5,000 times of charge-discharge cycles.Even in knotted shape,the fiber still shows excellent color contrast.This study provides a novel method to construct flexible electrochromic fiber and pave the way for the development of flexible optoelectronic devices,such as flexible and wearable displays.展开更多
Magnetic yolk-shell structured anatase-based microspheres were fabricated through successive and facile sol-gel coating on magnetite particles, followed by annealing treatments. Upon loading with gold nanoparticles, t...Magnetic yolk-shell structured anatase-based microspheres were fabricated through successive and facile sol-gel coating on magnetite particles, followed by annealing treatments. Upon loading with gold nanoparticles, the obtained functional magnetic microspheres as heterogeneous catalysts showed superior performance in catalyzing the epoxidation of styrene with extraordinary high conversion (89.5%) and selectivity (90.8%) towards styrene oxide. It is believed that the construction process of these fascinating materials features many implications for creating other functional nanocomposites.展开更多
Among various gas sensing materials, metal oxide semiconductors have shown great potential as resistive type sensors. The ordered porous structural metal oxide semiconductors with well-defined meso- or macro-pores che...Among various gas sensing materials, metal oxide semiconductors have shown great potential as resistive type sensors. The ordered porous structural metal oxide semiconductors with well-defined meso- or macro-pores chemically synthesized via soft-templating method and nanocasting strategy have high porosity, highly interconnected pore channels and high surface area with enormous active sites for interacting with gaseous molecules. These features enable them good performance in gas sensing, including high sensitivity, fast response and recovery, good selectivity. This review gives a comprehensive summary about the porous metal oxides with focus on the synthesis methods, structure related properties, as well as the modification strategies for gas sensing improved performances.展开更多
The rapid development of internet and internet of things brings new opportunities for the expansion of intelligent sensors,and acetone as a major disease detection indicator(i.e.,diabetes)making it become extremely im...The rapid development of internet and internet of things brings new opportunities for the expansion of intelligent sensors,and acetone as a major disease detection indicator(i.e.,diabetes)making it become extremely important clinical indicator.Herein,uniform mesoporous ZnO spheres were successfully synthesized via novel formaldehyde-assisted metal-ligand crosslinking strategy.In order to adjust the pore structure of mesoporous ZnO,various mesoporous ZnO spheres were synthesized by changing weight percentage of Zn(NO_(3))_(2)·6 H_(2)O to tannic acid(TA).Moreover,highly active heterojunction mesoporous ZnO/Co_(3)O_(4)has been fabricated based on as-prepared ultra-small Co_(3)O_(4)nanocrystals(ca.3 nm)and mesoporous ZnO spheres by flexible impregnation technique.Profit from nano-size effect and synergistic effect of p-n heterojunction,mesoporous ZnO/Co_(3)O_(4)exhibited excellent acetone sensing performance with high selectivity,superior sensitivity and responsiveness.Typically,5 wt%Co_(3)O_(4)embedded mesoporous ZnO sphere showed prominent acetone response(ca.46 for 50 ppm),which was about 11.5 times higher than that in pure ZnO sensing device,and it was also endowed high cyclic stability.The nanocrystals embedded hybrid material is expected to be used as promising efficient material in the field of catalysis and gas sensing.展开更多
In this study,a series of epoxy-based azo molecular glasses with four-arm architecture was synthesized based on an intermediate(MDGA-AN),which was obtained from ring-opening reaction between 4,4'-methylene-bis(N,N...In this study,a series of epoxy-based azo molecular glasses with four-arm architecture was synthesized based on an intermediate(MDGA-AN),which was obtained from ring-opening reaction between 4,4'-methylene-bis(N,N’-diglycidylaniline)and N-methylaniline.The azo compounds were then synthesized through azo-coupling reaction between MDGA-AN and diazonium salts of 4-nitroaniline,4-aminobenzonitrile,4-aminobenzoic acid,4-fluoroaniline and 4-methoxyaniline,respectively.The azo compounds were thoroughly characterized and the photoresponsive properties of their solid films were investigated at three different wavelengths(λex=488,532 and 589 nm).The results show that the electron-withdrawing groups on the azo chromophores can significantly affect the absorption band positions in visible light range,which shift to the longer wavelength with the enhanced push-pull effect.Both photoinduced birefringence and surface-relief-grating formation are closely related to the electronwithdrawing groups and excitation wavelengths of the actinic light,which show significant influences on the growth rates and saturated values of the photoinduced variations.In this series,the azo molecular glasses containing cyano and carboxyl groups as the electron-withdrawing groups show the significantly higher efficiency for both the photoinduced birefringence growth and the SRG formation compared with others under the same light irradiation conditions.The capability of the materials as a photo-storage medium is demonstrated by holographic recording.展开更多
Mesoporous late-transition metal oxides have great potential in applications of energy,catalysis and chemical sensing due to their unique physical and chemical properties.However,their synthesis via the flexible and s...Mesoporous late-transition metal oxides have great potential in applications of energy,catalysis and chemical sensing due to their unique physical and chemical properties.However,their synthesis via the flexible and scalable soft-template method remain a great challenge,due to the weak organic-inorganic interaction between the frequently used surfactants(e.g.,Pluronic-type block copolymers) and metal oxide precursors,and the low crystallization temperature of metal oxides.In this study,ordered mesoporous NiO with dual mesopores,high surface area and well-interconnected crystalline porous frameworks have been successfully synthesized via the facile solvent evaporation-induced co-assembly(EICA) method,by using lab-made amphiphilic diblock copolymer polystyrene-b-poly(4-vinylpyridine)(PS-b-P4 VP) as both the structure-directing agent(the soft template) and macromolecular chelating agents for nickel species,THF as the solvent,and nickel acetylacetonate(Ni(acac)2) as inorganic precursor.Similarly,by using Ni(acac)2 and Fe(acac)3 as the binary precursors,ordered mesoporous Fedoped NiO materials can be obtained,which have bimodal mesopores of large mesopores(32.5 nm) and secondary mesopores(4.0-11.5 nm) in the nanocrystal-assembled walls,high specific surface areas(~74.8 m^2/g) and large pore value(~0.167 cm^3/g).The obtained mesoporous Fe-doped NiO based gas sensor showed superior ethanol sensing performances with good sensitivity,high selectivity and fast response-recovery dynamics.展开更多
基金supported by National Research Foundation Investigatorship(No.NRF-NRFI201605)。
文摘Though flexible electrochromic devices have shown huge potential application in the fields of safety warning,display and smart windows,limited attention was paid on preparing flexible electrochromic fiber because of the difficulty in fabricating the multilayer electrochromic device structure in one-dimensional form.In this study,a flexible electrochromic nylon fiber based on Ag nanowires(NWs)/PEDOT:PSS/WO3 nanoparticles(NPs)(PEDOT:PSS=poly(3,4-ethylenedioxythiophene):polystyrenesulfonic acid)is successfully fabricated,delivering rapid color switching(2.5 and 9 s for bleaching and coloration)and high optical modulation(65.5%at 633 nm),and sustainable to repeated mechanical deformations.Ag NWs,PEDOT:PSS and WO3 NPs were dip-coated on the nylon fiber,resulting in an electrochromic fiber electrode with stable fiber resistance of 50-100Ω/10 cm,which can withstand mechanical deformation against 300 times of bending cycles with bending radius of 0.5 cm,and sustain 30 times of tape-peeling.During the galvanostatic tests,the capacitance of the electrochromic electrode can maintain 70%of the initial value even after 5,000 times of charge-discharge cycles.Even in knotted shape,the fiber still shows excellent color contrast.This study provides a novel method to construct flexible electrochromic fiber and pave the way for the development of flexible optoelectronic devices,such as flexible and wearable displays.
文摘Magnetic yolk-shell structured anatase-based microspheres were fabricated through successive and facile sol-gel coating on magnetite particles, followed by annealing treatments. Upon loading with gold nanoparticles, the obtained functional magnetic microspheres as heterogeneous catalysts showed superior performance in catalyzing the epoxidation of styrene with extraordinary high conversion (89.5%) and selectivity (90.8%) towards styrene oxide. It is believed that the construction process of these fascinating materials features many implications for creating other functional nanocomposites.
基金supported by the National Natural Science Foundation of China(Nos.51372041,51422202, and 21673048)the "Shu Guang" Project(No. 13SG02)supported by Shanghai Municipal Education Commission and Shanghai Education Development Foundation+3 种基金the National Youth Top-notch Talent Support Program in China, China Postdoctoral Science Foundation(No. KLH1615138)Shanghai Nature Science Foundation of China(Nos. 14ZR1416600 and 15ZR1402000)Shanghai Pujiang Program, China(No.16PJ1401100)the International Scientific Partnership Program ISPP at King Saud University for funding this research work through ISPP# 0094
文摘Among various gas sensing materials, metal oxide semiconductors have shown great potential as resistive type sensors. The ordered porous structural metal oxide semiconductors with well-defined meso- or macro-pores chemically synthesized via soft-templating method and nanocasting strategy have high porosity, highly interconnected pore channels and high surface area with enormous active sites for interacting with gaseous molecules. These features enable them good performance in gas sensing, including high sensitivity, fast response and recovery, good selectivity. This review gives a comprehensive summary about the porous metal oxides with focus on the synthesis methods, structure related properties, as well as the modification strategies for gas sensing improved performances.
基金financially supported by the National Natural Science Foundation of China(Nos.21673048,21875044,52073064,22005058 and 22005057)National Key R&D Program of China(No.2018YFA0209401)+3 种基金Key Basic Research Program of Science and Technology Commission of Shanghai Municipality(No.20JC1415300)Program of Shanghai Academic Research Leader(No.19XD1420300)the state key laboratory of Transducer Technology of China(No.SKT1904)supporting project number(No.RSP-2020/155)。
文摘The rapid development of internet and internet of things brings new opportunities for the expansion of intelligent sensors,and acetone as a major disease detection indicator(i.e.,diabetes)making it become extremely important clinical indicator.Herein,uniform mesoporous ZnO spheres were successfully synthesized via novel formaldehyde-assisted metal-ligand crosslinking strategy.In order to adjust the pore structure of mesoporous ZnO,various mesoporous ZnO spheres were synthesized by changing weight percentage of Zn(NO_(3))_(2)·6 H_(2)O to tannic acid(TA).Moreover,highly active heterojunction mesoporous ZnO/Co_(3)O_(4)has been fabricated based on as-prepared ultra-small Co_(3)O_(4)nanocrystals(ca.3 nm)and mesoporous ZnO spheres by flexible impregnation technique.Profit from nano-size effect and synergistic effect of p-n heterojunction,mesoporous ZnO/Co_(3)O_(4)exhibited excellent acetone sensing performance with high selectivity,superior sensitivity and responsiveness.Typically,5 wt%Co_(3)O_(4)embedded mesoporous ZnO sphere showed prominent acetone response(ca.46 for 50 ppm),which was about 11.5 times higher than that in pure ZnO sensing device,and it was also endowed high cyclic stability.The nanocrystals embedded hybrid material is expected to be used as promising efficient material in the field of catalysis and gas sensing.
基金financial support from the National Natural Science Foundation of China(Nos.51773108 and 51233002)
文摘In this study,a series of epoxy-based azo molecular glasses with four-arm architecture was synthesized based on an intermediate(MDGA-AN),which was obtained from ring-opening reaction between 4,4'-methylene-bis(N,N’-diglycidylaniline)and N-methylaniline.The azo compounds were then synthesized through azo-coupling reaction between MDGA-AN and diazonium salts of 4-nitroaniline,4-aminobenzonitrile,4-aminobenzoic acid,4-fluoroaniline and 4-methoxyaniline,respectively.The azo compounds were thoroughly characterized and the photoresponsive properties of their solid films were investigated at three different wavelengths(λex=488,532 and 589 nm).The results show that the electron-withdrawing groups on the azo chromophores can significantly affect the absorption band positions in visible light range,which shift to the longer wavelength with the enhanced push-pull effect.Both photoinduced birefringence and surface-relief-grating formation are closely related to the electronwithdrawing groups and excitation wavelengths of the actinic light,which show significant influences on the growth rates and saturated values of the photoinduced variations.In this series,the azo molecular glasses containing cyano and carboxyl groups as the electron-withdrawing groups show the significantly higher efficiency for both the photoinduced birefringence growth and the SRG formation compared with others under the same light irradiation conditions.The capability of the materials as a photo-storage medium is demonstrated by holographic recording.
基金supported by the NSF of China(Nos.51372041, 51422202,21673048,21875044,51822202 and 51772050)Key Basic Research Program of Science and Technology Commission of Shanghai Municipality (No.17JC1400100)+4 种基金Youth Top-notch Talent Support Program of ChinaShanghai Rising-Star Program(No. 18QA1400100)Youth Top-notch Talent Support Program of ShanghaiDHU distinguished Young Professor Programthe Fundamental Research Funds for the Central Universities
文摘Mesoporous late-transition metal oxides have great potential in applications of energy,catalysis and chemical sensing due to their unique physical and chemical properties.However,their synthesis via the flexible and scalable soft-template method remain a great challenge,due to the weak organic-inorganic interaction between the frequently used surfactants(e.g.,Pluronic-type block copolymers) and metal oxide precursors,and the low crystallization temperature of metal oxides.In this study,ordered mesoporous NiO with dual mesopores,high surface area and well-interconnected crystalline porous frameworks have been successfully synthesized via the facile solvent evaporation-induced co-assembly(EICA) method,by using lab-made amphiphilic diblock copolymer polystyrene-b-poly(4-vinylpyridine)(PS-b-P4 VP) as both the structure-directing agent(the soft template) and macromolecular chelating agents for nickel species,THF as the solvent,and nickel acetylacetonate(Ni(acac)2) as inorganic precursor.Similarly,by using Ni(acac)2 and Fe(acac)3 as the binary precursors,ordered mesoporous Fedoped NiO materials can be obtained,which have bimodal mesopores of large mesopores(32.5 nm) and secondary mesopores(4.0-11.5 nm) in the nanocrystal-assembled walls,high specific surface areas(~74.8 m^2/g) and large pore value(~0.167 cm^3/g).The obtained mesoporous Fe-doped NiO based gas sensor showed superior ethanol sensing performances with good sensitivity,high selectivity and fast response-recovery dynamics.