Hybrid catalysts based on iron phthalocyanine(FePc)have raised much attention due to their promising applications in electrocatalytic oxygen reduction reaction(ORR).Various hybridization strategies have been developed...Hybrid catalysts based on iron phthalocyanine(FePc)have raised much attention due to their promising applications in electrocatalytic oxygen reduction reaction(ORR).Various hybridization strategies have been developed for improving their activity and durability.However,the influence of different hybridization strategies on their catalytic performance remains unclear.In this study,Fe Pc was effectively distributed on molybdenum disulfide(MoS_(2))forming Fe Pc-based hybrid catalysts,namely Fe Pc-MoS_(2),Fe Pc*-MoS_(2),and Fe Pc-Py-MoS_(2),respectively,to disclose the related influence.Through direct hybridization,the stacked and highly dispersed Fe Pc on MoS_(2)resulted in Fe Pc-MoS_(2),and Fe Pc*-MoS_(2),respectively,in which the substrate and Fe Pc are mainly bound through van der Waals interactions.Through covalent hybridization strategy using pyridyl(Py)as a linker,Fe Pc-Py-MoS_(2)hybrid catalyst was prepared.Experimental and theoretical results disclosed that the linker hybridization of Fe Pc and MoS_(2)facilitated the exposure of Fe-N4 sites,maintained the intrinsic activity of Fe Pc by forming a more dispersed phase and increased the durability via Fe-N bonding,rendering the Fe Pc-Py-MoS_(2)an excellent ORR hybrid catalyst.Compared with van der Waals hybridized Fe Pc-MoS_(2)and Fe Pc*-MoS_(2)in alkaline media,the linker hybridized Fe Pc-Py-MoS_(2)showed an obviously enhanced ORR activity with a half-wave potential(E_(1/2))of 0.88 V vs RHE and an ultralow Tafel slope of 26 m V dec-1.Besides,the Fe Pc-Py-MoS_(2)exhibited a negligible decay of E_(1/2) after 50,000 CV cycles for ORR,showing its superior durability.This work gives us more insight into the influence of different hybrid strategies on Fe Pc catalysts and provides further guidance for the development of highly efficient and durable ORR catalysts.展开更多
Electrochromic smart windows have attracted much attention in energy-saving buildings because of their ability to selectively modulate visible(VIS)and near-infrared(NIR)light transmittance.As is known,the NIR region a...Electrochromic smart windows have attracted much attention in energy-saving buildings because of their ability to selectively modulate visible(VIS)and near-infrared(NIR)light transmittance.As is known,the NIR region accounts for about 50%of the total solar radiation.Therefore,reducing the NIR transmittance of windows will play a crucial role in reducing the energy consumption of buildings.However,for most of the reported electrochromic materials(ECMs)-based windows,it remains a longlasting challenge about how to achieve a low NIR transmittance during the past decades.In this work,we synthesize oxygendeficient tungsten oxide(WO_(3−x))nanoflowers(NFs)by a simple and efficient method that is facile for their mass production.The WO_(3−x)NFs exhibit low NIR transmittance of only 4.11%,0.60%,and 0.19%at 1200,1600,and 1800 nm,respectively,due to the localized surface plasmon resonance(LSPR)effect.Besides,the WO_(3−x)NFs exhibit an excellent dual-band modulating ability for both VIS and NIR light.They are able to operate in three distinct modes,including a bright mode,a cool mode,and a dark mode.Moreover,the WO_(3−x)NFs exhibit a fast bleaching/coloring time(1.54/6.67 s),and excellent cycling stability(97.75%of capacity retention after 4000 s).展开更多
Carbon nanotube fibers(CNTFs)are endowed with excellent mechanical,electrical,and thermal properties and are considered promising candidates in numerous cutting-edge fields.However,the inherent black color of CNTFs hi...Carbon nanotube fibers(CNTFs)are endowed with excellent mechanical,electrical,and thermal properties and are considered promising candidates in numerous cutting-edge fields.However,the inherent black color of CNTFs hinders their practical application in fields with high aesthetic requirements such as wearable devices and smart textiles.Due to the smooth surface and chemical inertness,CNTFs are hard to be dyed by conventional chemical dyes or colorful inks.Herein,we realize a structural coloration of CNTFs by coating them with two metal oxide layers via atomic layer deposition.The three elements of color,that is,hue,saturation,and brightness,can be controlled by adjusting the types and thickness of each oxide layer.Colorful CNTFs with wide color gamut and high saturation are achieved through different combinations.A film interference model is also established to reveal the mechanism of the structural coloration,which is a comprehensive result of thin-film interference and surface roughness briefly.The calculated reflectance well fits the measured results by introducing surface roughness parameters.Moreover,the colored CNTFs are not iridescent because of retinal signal delay,which will further expand their applications.展开更多
Materials are foundations of human civilization.From the Stone Age to the present new material age,the history of human civilization is also a history of the development of materials.The mass production of a new gener...Materials are foundations of human civilization.From the Stone Age to the present new material age,the history of human civilization is also a history of the development of materials.The mass production of a new generation of materials with strength,flexibility and fatigue resistance that are orders of magnitude higher than the current materials is of great importance in both science and engineering.展开更多
基金financial support from the National Natural Science Foundation of China(51872156,22075163)the National Key Research Program(2020YFC2201103,2020YFA0210702)+1 种基金the China Postdoctoral Science Foundation funded project(2020 M670343)the Shuimu Tsinghua Scholar Program。
文摘Hybrid catalysts based on iron phthalocyanine(FePc)have raised much attention due to their promising applications in electrocatalytic oxygen reduction reaction(ORR).Various hybridization strategies have been developed for improving their activity and durability.However,the influence of different hybridization strategies on their catalytic performance remains unclear.In this study,Fe Pc was effectively distributed on molybdenum disulfide(MoS_(2))forming Fe Pc-based hybrid catalysts,namely Fe Pc-MoS_(2),Fe Pc*-MoS_(2),and Fe Pc-Py-MoS_(2),respectively,to disclose the related influence.Through direct hybridization,the stacked and highly dispersed Fe Pc on MoS_(2)resulted in Fe Pc-MoS_(2),and Fe Pc*-MoS_(2),respectively,in which the substrate and Fe Pc are mainly bound through van der Waals interactions.Through covalent hybridization strategy using pyridyl(Py)as a linker,Fe Pc-Py-MoS_(2)hybrid catalyst was prepared.Experimental and theoretical results disclosed that the linker hybridization of Fe Pc and MoS_(2)facilitated the exposure of Fe-N4 sites,maintained the intrinsic activity of Fe Pc by forming a more dispersed phase and increased the durability via Fe-N bonding,rendering the Fe Pc-Py-MoS_(2)an excellent ORR hybrid catalyst.Compared with van der Waals hybridized Fe Pc-MoS_(2)and Fe Pc*-MoS_(2)in alkaline media,the linker hybridized Fe Pc-Py-MoS_(2)showed an obviously enhanced ORR activity with a half-wave potential(E_(1/2))of 0.88 V vs RHE and an ultralow Tafel slope of 26 m V dec-1.Besides,the Fe Pc-Py-MoS_(2)exhibited a negligible decay of E_(1/2) after 50,000 CV cycles for ORR,showing its superior durability.This work gives us more insight into the influence of different hybrid strategies on Fe Pc catalysts and provides further guidance for the development of highly efficient and durable ORR catalysts.
基金the Tsinghua-Toyota Joint Research Fund,the National Key Research Program(Nos.2020YFA0210702 and 2020YFC2201103)the National Natural Science Foundation of China(Nos.51872156 and 22075163)the China Postdoctoral Science Foundation funded project(No.2022M721808).
文摘Electrochromic smart windows have attracted much attention in energy-saving buildings because of their ability to selectively modulate visible(VIS)and near-infrared(NIR)light transmittance.As is known,the NIR region accounts for about 50%of the total solar radiation.Therefore,reducing the NIR transmittance of windows will play a crucial role in reducing the energy consumption of buildings.However,for most of the reported electrochromic materials(ECMs)-based windows,it remains a longlasting challenge about how to achieve a low NIR transmittance during the past decades.In this work,we synthesize oxygendeficient tungsten oxide(WO_(3−x))nanoflowers(NFs)by a simple and efficient method that is facile for their mass production.The WO_(3−x)NFs exhibit low NIR transmittance of only 4.11%,0.60%,and 0.19%at 1200,1600,and 1800 nm,respectively,due to the localized surface plasmon resonance(LSPR)effect.Besides,the WO_(3−x)NFs exhibit an excellent dual-band modulating ability for both VIS and NIR light.They are able to operate in three distinct modes,including a bright mode,a cool mode,and a dark mode.Moreover,the WO_(3−x)NFs exhibit a fast bleaching/coloring time(1.54/6.67 s),and excellent cycling stability(97.75%of capacity retention after 4000 s).
基金National Natural Science Foundation of China,Grant/Award Numbers:22075163,51872156National Key Research Program,Grant/Award Numbers:2020YFC2201103,2020YFA0210702。
文摘Carbon nanotube fibers(CNTFs)are endowed with excellent mechanical,electrical,and thermal properties and are considered promising candidates in numerous cutting-edge fields.However,the inherent black color of CNTFs hinders their practical application in fields with high aesthetic requirements such as wearable devices and smart textiles.Due to the smooth surface and chemical inertness,CNTFs are hard to be dyed by conventional chemical dyes or colorful inks.Herein,we realize a structural coloration of CNTFs by coating them with two metal oxide layers via atomic layer deposition.The three elements of color,that is,hue,saturation,and brightness,can be controlled by adjusting the types and thickness of each oxide layer.Colorful CNTFs with wide color gamut and high saturation are achieved through different combinations.A film interference model is also established to reveal the mechanism of the structural coloration,which is a comprehensive result of thin-film interference and surface roughness briefly.The calculated reflectance well fits the measured results by introducing surface roughness parameters.Moreover,the colored CNTFs are not iridescent because of retinal signal delay,which will further expand their applications.
基金supported by the National Natural Science Foundation of China(22075163 and 51872156)the National Key Research and Development Program of China(2020YFC2201103,2020YFA0210702)。
文摘Materials are foundations of human civilization.From the Stone Age to the present new material age,the history of human civilization is also a history of the development of materials.The mass production of a new generation of materials with strength,flexibility and fatigue resistance that are orders of magnitude higher than the current materials is of great importance in both science and engineering.
