Conducting polymers(CPs),including poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate)(PEDOT:PSS),are promising coating materials for neural electrodes.However,the weak adhesion of CP coatings to substrates such a...Conducting polymers(CPs),including poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate)(PEDOT:PSS),are promising coating materials for neural electrodes.However,the weak adhesion of CP coatings to substrates such as platinum-iridium is a significant challenge that limits their practical application.To address this issue,we used femtosecond laser-prepared hierarchical structures on platinum-iridium(Pt-Ir)substrates to enhance the adhesion of PEDOT:PSS coatings.Next,we used cyclic voltammetry(CV)stress and accelerated aging tests to evaluate the stability of both drop cast and electrodeposited PEDOT:PSS coatings on Pt-Ir substrates,both with and without hierarchical structures.Our results showed that after 2000 CV cycles or five weeks of aging at 60℃,the morphology and electrochemical properties of the coatings on the Pt-Ir substrates with hierarchical structures remained relatively stable.In contrast,we found that smooth Pt-Ir substrate surfaces caused delamination of the PEDOT:PSS coating and exhibited both decreased charge storage capacity and increased impedance.Overall,enhancing the stability of PEDOT:PSS coatings used on common platinum-iridium neural electrodes offers great potential for improving their electrochemical performance and developing new functionalities.展开更多
Gas adsorption remains an attractive area of research.The hierarchical structure can reduce diffusion limitations and facilitate molecular transport,while acid sites can be used as adsorption sites.These make zeolites...Gas adsorption remains an attractive area of research.The hierarchical structure can reduce diffusion limitations and facilitate molecular transport,while acid sites can be used as adsorption sites.These make zeolites widely used in the field of gas adsorption.How to obtain zeolite adsorbents with better adsorption properties by modulating the hierarchical structure and acid sites is a pressing issue nowadays.This review highlights the strategies to modulate the hierarchical structure as well as the acid sites;and then explains how these strategies are achieved.The mechanism of zeolite adsorption on gases is then described in terms of these two properties.Lastly,the adsorption properties of zeolites for certain gases under specific conditions are summarised.An outlook of zeolite hierarchical structures and acid site modulation strategies is given.展开更多
Currently,the hierarchical structure is one of the most effective means to enhance the strength and plasticity of metal materials,since the strain localization can be effectively delayed by the coordination of the uni...Currently,the hierarchical structure is one of the most effective means to enhance the strength and plasticity of metal materials,since the strain localization can be effectively delayed by the coordination of the unique microstructure.In this study,a hierarchical structure of Mg-15Gd-1Zn-0.4Zr(GZ151K)alloys containing grain,twin,and precipitation structural units was prepared by ultrasonic surface rolling process(USRP)and recrystallization annealing(RU).The results showed that the stress gradient generated by USRP formed a twin gradient structure,which will activate the twin-assisted precipitation(TAP)effect and twin-induced recrystallization(TIR)effect during RU.Then,the twin gradient structure transformed into a twin-precipitation gradient structure,and finally into a hierarchical structure with grain-twinprecipitation as the increasement of recrystallization degree.Besides,the dual gradient structure with twin and precipitation structural units had the highest strength and microhardness owing to the precipitation strengthening.However,the hierarchical structure with grain,twin,and precipitation structural units exhibited the most excellent combination of strength and plasticity under grain refinement and precipitation strengthening.展开更多
Flexible attachment actuators are popular in a wide range of applications,owing to their flexibility and highly reliable attachment.However,their reversible adhesion performance depends on the actual effective contact...Flexible attachment actuators are popular in a wide range of applications,owing to their flexibility and highly reliable attachment.However,their reversible adhesion performance depends on the actual effective contact area and peel angle during operation.Therefore,a good actuator must ensure a uniform and reliable pre-pressure load on an adhesive surface,to increase the effective contact area of the attached surface,thereby maximizing adhesion.This study was inspired by fusion bionics for designing a hierarchical attachment structure with vacuum-adsorption and dry-adhesion mechanisms.The designed structure used the normal force under the negative pressure of a suction cup as a stable source of a pre-pressure load.By optimizing the rigid and flexible structural layers of the attachment structure,a load was applied uniformly to the adhesion area;thus,reliable attachment was achieved by self-preloading.The structure achieved detachment by exploiting the large deformation of a pneumatic structure under a positive pressure.The hierarchical attachment structure achieved up to 85%of the optimal performance of the adhesive surface.Owing to its self-preloading and reliable attachment characteristics,the designed structure can be used as an attachment unit in various complex scenarios,such as small,lightweight climbing platforms and the transport of objects in long,narrow pipelines.展开更多
Some living organisms with hierarchical structures in nature have received extensive attention in various fields.The hierarchical structure with multiple pores,a large number of solid-gas interfaces and tortuous condu...Some living organisms with hierarchical structures in nature have received extensive attention in various fields.The hierarchical structure with multiple pores,a large number of solid-gas interfaces and tortuous conduction paths provide a new direction for the development of thermal insulation materials,making the living creatures under these extreme conditions become the bionic objects of scientific researchers.In this review,the research progress of bionic hierarchical structure in the field of heat insulation is highlighted.Polar bears,cocoons,penguin feathers and wool are typical examples of heat preservation hierarchy in nature to introduce their morphological characteristics.At the same time,the thermal insulation mechanism,fractal model and several preparation methods of bionic hierarchical structures are emphatically discussed.The application of hierarchical structures in various fields,especially in thermal insulation and infrared thermal stealth,is summarised.Finally,the hierarchical structure is prospected.展开更多
Amplifying the intrinsic wettability of substrate material by changing the solid/liquid contact area is considered to be the main mechanism for controlling the wettability of rough or structured surfaces.Through theor...Amplifying the intrinsic wettability of substrate material by changing the solid/liquid contact area is considered to be the main mechanism for controlling the wettability of rough or structured surfaces.Through theoretical analysis and experimental exploration,we have found that in addition to this wettability structure amplification effect,the surface structure also simultaneously controls surface wettability by regulating the wetting state via changing the threshold Young angles of the Cassie-Baxter and Wenzel wetting regions.This wetting state regulation effect provides us with an alternative strategy to overcome the inherent limitation in surface chemistry by tailoring surface structure.The wetting state regulation effect created by multi-scale hierarchical structures is quite significant and plays is a crucial role in promoting the superhydrophobicity,superhydrophilicity and the transition between these two extreme wetting properties,as well as stabilizing the Cassie-Baxter superhydrophobic state on the fabricated lotus-like hierarchically structured Cu surface and the natural lotus leaf.展开更多
3D-printed Porous Titanium Alloy Implants(pTi),owing to their biologically inertness and relatively smooth surface morphology,adversely affect the biological functions of surrounding cells.To address the challenges,co...3D-printed Porous Titanium Alloy Implants(pTi),owing to their biologically inertness and relatively smooth surface morphology,adversely affect the biological functions of surrounding cells.To address the challenges,constructing a bioinspired interface that mimics the hierarchical structure of bone tissue can enhance the cellular functions of cells.In this context,Hollow Mesoporous Silica Nanoparticles(HMSNs),renowned for their unique physicochemical properties and superior biocompatibility,offer a promising direction for this research.In this research,the initially synthesized HMSNs were used to construct a“hollow-mesoporous-macroporous”hierarchical bioinspired coating on the pTi surface through the Layer-by-Layer technique.Simultaneously,diverse morphologies of coatings were established by adjusting the deposition strategy of PDDA/HMSNs on the pTi surface(pTi-HMSN-2,pTi-HMSN-4,pTi-HMSN-6).A range of techniques were employed to investigate the physicochemical properties and regulation of cellular biological functions of the diverse HMSN coating strategies.Notably,the pTi-HMSN-4 and pTi-HMSN-6 groups exhibited the uniform coatings,leading to a substantial enhancement in surface roughness and hydrophilicity.Meantime,the coating constructed strategy of pTi-HMSN-4 possessed commendable stability.Based on the aforementioned findings,both pTi-HMSN-4 and pTi-HMSN-6 facilitated the adhesion,spreading,and pseudopodia extension of BMSCs,which led to a notable upsurge in the expression levels of vinculin protein in BMSCs.Comprehensive analysis indicates that the coating,when PDDA/HMSNs are deposited four times,possesses favorable overall performance.The research will provide a solid theoretical basis for the translation of HMSN bioinspired coatings for orthopedic implants.展开更多
Development of metal oxide semiconductors-based methane sensors with good response and low power consumption is one of the major challenges to realize the real-time monitoring of methane leakage.In this work,a self-as...Development of metal oxide semiconductors-based methane sensors with good response and low power consumption is one of the major challenges to realize the real-time monitoring of methane leakage.In this work,a self-assembled mulberry-like ZnO/SnO_(2)hierarchical structure is constructed by a two-step hydrothermal method.The resultant sensor works at room temperature with excellent response of~56.1%to 2000 ppm CH_(4)at 55%relative humidity.It is found that the strain induced at the ZnO/SnO_(2)interface greatly enhances the piezoelectric polarization on the ZnO surface and that the band bending results in the accumulation of chemically adsorbed O_(2)^(-)ions close to the interface,leading to significant improvement in the sensing performance of the methane gas sensor at room temperature.展开更多
Flower-like tin oxide-supported platinum（Pt/SnOx） with a hierarchical structure was synthesized by a hydrothermal method and characterized by XRD,SEM,TEM,high resolution TEM,XPS and nitrogen adsorption.The flower-li...Flower-like tin oxide-supported platinum（Pt/SnOx） with a hierarchical structure was synthesized by a hydrothermal method and characterized by XRD,SEM,TEM,high resolution TEM,XPS and nitrogen adsorption.The flower-like Pt/SnOx microspheres of 1 μm in diameter were composed of staggered petal-like nanosheets with a thickness of 20 nm.Pt nanoparticles（NPs） of 2-3 nm were well dispersed on the SnOx nanosheets.The catalyst was tested in the catalytic oxidation of gaseous formaldehyde（HCHO） at room temperature,and exhibited enhanced activity compared to Pt NPs supported on commercial SnO and ground SnOx.HCHO removal of 87%was achieved over the hierarchical Pt/SnOx after 1 h of reaction,which was 1.5 times that over the ground SnOx-supported Pt（Pt/g-SnOx）,and the high activity was maintained after six recycles,showing the high stability of this catalyst.HCHO decomposition kinetics was modeled as a second order reaction.The reaction rate constant for Pt/SnOx was 5.6 times higher than Pt/g-SnOx.The hierarchical pore structure was beneficial for the diffusion and adsorption of HCHO molecules,and the highly dispersed Pt NPs on the SnOx nanosheets were the active sites for the oxidative decomposition of HCHO into CO2 and H2O.This study provided a promising approach for designing efficient catalysts for indoor HCHO removal at ambient temperature.展开更多
Based on the general [Mo] equivalent criterion and d-electron orbital theory, a new ultrahigh-strength βtitanium alloy with eight major elements(Ti-4.5Al-6.5Mo-2Cr-2.6Nb-2Zr-2Sn-1V, TB17) for industrial applications ...Based on the general [Mo] equivalent criterion and d-electron orbital theory, a new ultrahigh-strength βtitanium alloy with eight major elements(Ti-4.5Al-6.5Mo-2Cr-2.6Nb-2Zr-2Sn-1V, TB17) for industrial applications was developed. An ingot of five tons was successfully melted by thrice vacuum consumable arc melting. The microstructure and elements partitioning of different conditions were investigated systematically. The results suggest that the hierarchical structures of micro-scale first α phase(αf), nano-scale secondary α phase(αs), and ultrafine FCC substructures can be tailored by solution plus aging(STA) heat treatment. The lateral and epitaxial growth of αfphase promotes the HCP-α to FCC substructure transformation with the help of elements partitioning during the aging process. Moreover, the element V, generally regarded as β stabilizer, is found to mainly concentrate in the Al-rich αfphase in this study probably due to its relatively lower content and the strong bonding energy of Al-V. The hierarchical structure has a strong interaction with dislocations, which contributes to achieve a superhigh strength of 1376 MPa.In addition, the plastic strain is partitioned in the multi-scale precipitates(such as the α and FCC substructures) and β matrix, resulting in a considerable plasticity. TEM observation demonstrates that high density entangled dislocations at interfaces and mechanical twins exist in the STA sample after tensile test. It can be deduced that both dislocation slipping and twinning mechanisms are present in this alloy.Therefore, TB17 alloy can serve as an excellent candidate for structural materials on aircrafts that require high strength and lightweight.展开更多
The utilization of all-solid-state electrolytes is considered to be an effective way to enhance the safety performance of lithium metal batteries.However,the low ionic conductivity and poor interface compatibility gre...The utilization of all-solid-state electrolytes is considered to be an effective way to enhance the safety performance of lithium metal batteries.However,the low ionic conductivity and poor interface compatibility greatly restrict the development of all-solid-state battery.In this study,a composite electrolyte combining the electrospun polyamide 6(PA6)nanofiber membrane with hierarchical structure and the polyethylene oxide(PEO)polymer is investigated.The introduction of PA6 nanofiber membrane can effectively reduce the crystallinity of the polymer,so that the ionic conductivity of the electrolyte can be enhanced.Moreover,it is found that the presence of finely branched fibers in the hierarchical structure PA6 membrane allows the polar functional groups(C=O and N-H bonds)to be fully exposed,which provides sufficient functional sites for lithium ion transport and helps to regulate the uniform deposition of lithium metal.Moreover,the hierarchical structure can enhance the mechanical strength(9.2 MPa)of the electrolyte,thereby effectively improving the safety and cycle stability of the battery.The prepared Li/Li symmetric battery can be stably cycled for 1500 h under 0.3 mA cm^(-2) and 60℃.This study demonstrates that the prepared electrolyte has excellent application prospects in the next generation all-solid-state lithium metal batteries.展开更多
In the present research, hierarchical structure observation and mechanical property characterization for a type of biomaterial are carried out. The investigated bioma- terial is Hyriopsis cumingii, a typical limnetic ...In the present research, hierarchical structure observation and mechanical property characterization for a type of biomaterial are carried out. The investigated bioma- terial is Hyriopsis cumingii, a typical limnetic shell, which consists of two different structural layers, a prismatic ＂pillar＂ structure and a nacreous ＂brick and mortar＂ structure. The prismatic layer looks like a ＂pillar forest＂ with variationsection pillars sized on the order of several tens of microns. The nacreous material looks like a ＂brick wall＂ with bricks sized on the order of several microns. Both pillars and bricks are composed of nanoparticles. The mechanical properties of the hierarchical biomaterial are measured by using the nanoindentation test. Hardness and modulus are measured for both the nacre layer and the prismatic layer, respectively. The nanoindentation size effects for the hierarchical structural materials are investigated experimentally. The results show that the prismatic nanostructured material has a higher stiffness and hardness than the nacre nanostructured material. In addition, the nanoindentation size effects for the hierarchical structural materials are described theoretically, by using the trans-scale mechanics theory considering both strain gradient effect and the surface/interface effect. The modeling results are consistent with experimental ones.展开更多
In this paper,a three-dimensional(3D)hierar-chical ZnO structure consisting of nanosheets modified with ultrafine NiO particles was synthesized via a facile two-step chemical precipitate method.Various techniques char...In this paper,a three-dimensional(3D)hierar-chical ZnO structure consisting of nanosheets modified with ultrafine NiO particles was synthesized via a facile two-step chemical precipitate method.Various techniques characterized the as-synthesized ZnO/NiO composites and pure ZnO.The p-NiO/n-ZnO junctions formed between adjacent ZnO and NiO nanoparticles,improving the gas sensing performance.The ZnO/NiO composite with the Ni:Zn atomic ratio of 7.42:100 exhibited the best iso-propanol sensing properties.Compared to pure ZnO,it showed high selectivity and sensitivity(R_(a)/R_(g)=221.3 toward 400×10^(-6)isopropanol),fast response rate(less than 10 s),short recovery time,and simultaneously low operating temperature.Also,the ZnO/NiO composite exhibited a wide sensing range(1×10^(-6)-1000×10^(-6))to isopropanol and processed good long-term stability.The experimental results suggested the potential application in fabricating efficient isopropanol sensors using this ZnO/NiO composite.The enhanced isopropanol sensing mech-anism is also discussed in charge transfer between heterojunctions,surface area,and surface defects.展开更多
In order to enhance the interfacial adhesion of carbon fiber(CF)and polymer matrix,a multiscale gradient modulus intermediate layer with rigid-flexible(GO-PA)hierarchical structure was designed and fabricated between ...In order to enhance the interfacial adhesion of carbon fiber(CF)and polymer matrix,a multiscale gradient modulus intermediate layer with rigid-flexible(GO-PA)hierarchical structure was designed and fabricated between CFs and matrix by a facile and businesslike strategy.The polarity,roughness and wettability of CFs surface as well as the thickness of intermediate layer in composite have been significantly increased after rigid-flexible hierarchical structure was constructed.The IFSS,ILSS,compression and impact toughness manifested that the hierarchical structure could bring about a fantastic improvement(76.8%,46.4%,40.7%and 37.8%)for the interfacial and mechanical properties than other previous reports.Consequently,the establishment of CF surface with gradient modulus rigid-flexible hierarchical structure via regulation of nanoparticles and polymer array would open a new,viable and promising route to obtaining high-performance composites.展开更多
In this work,hierarchical hybrid composites consisting of porous three-dimensional reduced graphene oxide(3D-rGO)skeleton and lamellar boron nitride(BN)/silicon carbide(SiC)coatings are prepared by chemical vapor infi...In this work,hierarchical hybrid composites consisting of porous three-dimensional reduced graphene oxide(3D-rGO)skeleton and lamellar boron nitride(BN)/silicon carbide(SiC)coatings are prepared by chemical vapor infiltration(CVI)process.The graphene framework prepared by 3D printing and frozen self-assembly exhibits a lightweight structure and a perforated conductive network,which extends the transmission path of incident microwaves.The introduced ceramic coatings can effectively tune the impedance matching degree and supply a lossy phase,and the hierarchical structure of the composites enhances the multiple scattering of the incident microwaves.As expected,the 3D-rGO/BN/SiC composites possess an excellent absorbing performance with a minimum reflection loss value of–37.8 dB,and the widest effective absorbing bandwidth(RL<–10 dB)of 5.90 GHz is obtained.The controllable fabrication of composites can provide a guideline for rational design and fabrication of high-performance electromagnetic waves absorbing materials in practical applications.展开更多
In this work the flower-like hierarchical structures(HS) based on 3 D pristine ZnO,ZnO:Eu^3+ and ZnO:Eu^3+ @Au were successfully obtained by a template-free solvothermal and deposition-precipitation method.The decolor...In this work the flower-like hierarchical structures(HS) based on 3 D pristine ZnO,ZnO:Eu^3+ and ZnO:Eu^3+ @Au were successfully obtained by a template-free solvothermal and deposition-precipitation method.The decolorization/photodegradation of these structures towards model organic dye(rhodamine 6 G) was studied.The synthesized ZnO-based HS were characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM),UV-vis and photoluminescence(PL) spectroscopies.The proposed synthesis approaches allow to obtain highly crystalline 3 D ZnO,ZnO:Eu^3+ and ZnO:Eu^3+ @Au composites.Results of scanning microscopy show that ZnO flower-like HS are assemblies from smaller components,forming larger ones,the whole ZnO structure was approximately 3 μm.Au nanoparticles(size^10 nm)are successfully deposited on ZnO HS surface.Luminescent studies show that ZnO is an ideal matrix for incorporation of Eu^3+ ions in broad concentration range(Eu^3+=1.0 at%-5.0 at%) with an efficient red luminescence.The strong UV emission in ZnO,as well as ZnO;Eu^3+HS is observed under 325 nm excitation.Doping of ZnO HS matrix by Eu^3+ions leads to the red shift of deep level emission peak(DLE).The PL intensity reaches the maximum up to 5 at% Eu^3+.The photocatalytic properties of ZnO and ZnO:Eu^3+ @Au HS were investigated under UV-Vis light irradiation towards rhodamine 6 G.The obtained results demonstrate the synergetic effect of the deposited gold nanoparticles and Eu3^+ doping on photocatalytic activity of ZnO:Eu^3+@Au HS in comparison to pristine ZnO and ZnO:Eu^3+ HS.展开更多
Soy protein-based composite film is a potential replacement for petroleum-based film with multipurpose applica-tions and cleaner production.It is difficult to improve both the tensile strength and toughness of a prote...Soy protein-based composite film is a potential replacement for petroleum-based film with multipurpose applica-tions and cleaner production.It is difficult to improve both the tensile strength and toughness of a protein-based film without sacrificing its elongation.In this study,inspired by the hierarchical structure of nacre,a facile yet delicate strategy was developed to fabricate a novel bio-based film with excellent toughness and high strength.Triglycidylamine(TGA)crosslinked soy protein(SPI)as hard phase and thermoplastic polyurethane elastomer(TPU)as soft phase comprise an alternative lay-up hierarchical structure.The interface of these two phases is enhanced using triglycidylamine(TGA)surface-modified TPU(MTPU).The tensile strength of SPI/MTPU/TGA films increases by 392%to 7.78 MPa and their toughness increases by 391%to 8.50 MJ/m^(3) compared to soy protein/glycerol film.The proposed hierarchical structure can also be extended to other high-performance materials and polymers.展开更多
For clarifying the hierarchical patterns of population structure of soybean landraces in China, the seven clusters previously identified using Bayesian clustering of 1 504 soybean landraces based on SSR markers genoty...For clarifying the hierarchical patterns of population structure of soybean landraces in China, the seven clusters previously identified using Bayesian clustering of 1 504 soybean landraces based on SSR markers genotyping data were further analyzed. Using the largest value of AK, these landraces could be split into 20 sub-clusters, which was supported by highly significant pairwise Fst-values and generally in accordance with the geographic origin and sowing types. The autumn-sowing types ended up in one distinct sub-cluster from the otherwise summer-sowing type, where the autumn- sowing types are most likely derived from. The division into 20 sub-clusters explained 7.3% of the genetic variation, next to 9.7% present among the seven clusters, 81.1% residing among landraces within sub-clusters, and 1.9% within the landraces. The distribution pattern of genetic diversity among the sub-clusters of each cluster was uneven, with two HSuM sub-clusters （Central China） and some South China sub-clusters showing significantly higher level of genetic diversity.展开更多
ZnO nanosheets and nanoflakes were grown on alumina particles in the absence of surfactants via heterogeneous precipitation using urea, zinc acetate and bayerite as precursors. Thermo-gravimetric analysis （TGA）, X-r...ZnO nanosheets and nanoflakes were grown on alumina particles in the absence of surfactants via heterogeneous precipitation using urea, zinc acetate and bayerite as precursors. Thermo-gravimetric analysis （TGA）, X-ray diffraction （XRD） and Fourier transform infrared spectroscopy （FTIR） were used and the results indicated the formation of only two phases： wurtzite-type ZnO and γ-Al2O3. ZnO nanoflakes were grown on alumina particles in the samples with ZnO content of 40 and 60 wt%, By increasing the ZnO content to 80 wt%, a porous hierarchical structure of ZnO with nanosheet arrays appeared. Both of these nanoflakes and nanosheets were about 40-80 nm in thickness and about 1-2 μm in diameter. It was proposed that Zns（CO3）2（OH）6 nuclei undergo higher growth rates in thin sheets at edges of bayerite particles with a higher surface energy. The Brunauer-Emmett-Teller （BET） measurements proved a reachable high surface area for hierarchical structures of ZnO nanosheets, which could mainly be attributed to their unique growth on alumina particles. Also, UV absorption results revealed that ZnO--Al2O3 compositions still show the UV characteristic absorption of ZnO, which can evidence the presence of photocatalytic properties in ZnO-Al2O3 compositions.展开更多
Wettability and the light-trapping effect of FeSe2 particles with a micro-nano hierarchical structure have been inves- tigated. Particles are synthesized by an improved solvothermal method, wherein hexadecyl trimetbyl...Wettability and the light-trapping effect of FeSe2 particles with a micro-nano hierarchical structure have been inves- tigated. Particles are synthesized by an improved solvothermal method, wherein hexadecyl trimetbyl ammonium bromide （CTAB） is employed as a surfactant. After modifying the particles with heptadecafluorodecyltrimethoxy-silane （HTMS）, we find that the water contact angle （WCA） of the FeSe2 particles increases by 6.1~ and the water sliding angle （WSA） decreases by 2.5~ respectively, and the diffuse reflectivity decreases 29.4% compared with similar FeSe2 particles synthe- sized by the conventional method. The growth process of the particles is analyzed and a growth scenario is given. Upon altering the PH values of the water, we observe that the superhydrophobic property is maintained quite consistently across a wide PH range of 1-14. Moreover, the modified particles were also found to be superoleophobic. To the best of our knowledge, there is no systematic research on the wettability of FeSe2 particles, so our research provides a reference for other researchers.展开更多
基金supported by the National Key Research and Development Program of China(No.2021YFC2400201)the National Natural Science Foundation of China(No.81830033)+1 种基金the Natural Science Foundation of Fujian Province,China(No.2023J05097)the Young and Middle-aged Teacher Education Research Project of the Education Department of Fujian Province,China(No.JAT220004)。
文摘Conducting polymers(CPs),including poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate)(PEDOT:PSS),are promising coating materials for neural electrodes.However,the weak adhesion of CP coatings to substrates such as platinum-iridium is a significant challenge that limits their practical application.To address this issue,we used femtosecond laser-prepared hierarchical structures on platinum-iridium(Pt-Ir)substrates to enhance the adhesion of PEDOT:PSS coatings.Next,we used cyclic voltammetry(CV)stress and accelerated aging tests to evaluate the stability of both drop cast and electrodeposited PEDOT:PSS coatings on Pt-Ir substrates,both with and without hierarchical structures.Our results showed that after 2000 CV cycles or five weeks of aging at 60℃,the morphology and electrochemical properties of the coatings on the Pt-Ir substrates with hierarchical structures remained relatively stable.In contrast,we found that smooth Pt-Ir substrate surfaces caused delamination of the PEDOT:PSS coating and exhibited both decreased charge storage capacity and increased impedance.Overall,enhancing the stability of PEDOT:PSS coatings used on common platinum-iridium neural electrodes offers great potential for improving their electrochemical performance and developing new functionalities.
基金supported by“Shanghai Science and Technology Innovation Action Plan”-Baoshan Transformation Development Science and Technology Special Project (No.21SQBS01100)the National Natural Science Foundation of China (Nos.22276137 and52170087)。
文摘Gas adsorption remains an attractive area of research.The hierarchical structure can reduce diffusion limitations and facilitate molecular transport,while acid sites can be used as adsorption sites.These make zeolites widely used in the field of gas adsorption.How to obtain zeolite adsorbents with better adsorption properties by modulating the hierarchical structure and acid sites is a pressing issue nowadays.This review highlights the strategies to modulate the hierarchical structure as well as the acid sites;and then explains how these strategies are achieved.The mechanism of zeolite adsorption on gases is then described in terms of these two properties.Lastly,the adsorption properties of zeolites for certain gases under specific conditions are summarised.An outlook of zeolite hierarchical structures and acid site modulation strategies is given.
基金supported by the National Key Research and Development Program of China(No.2021YFB3501001)the National Natural Science Foundation of China(Nos.52061028,and 52061039)+1 种基金the Natural Science Foundation of Jiangxi Province(No.20212BAB204049)the Interdisciplinary Innovation Fund of Nanchang University(IIFNCU),China(No.9166–27060003-ZD05).
文摘Currently,the hierarchical structure is one of the most effective means to enhance the strength and plasticity of metal materials,since the strain localization can be effectively delayed by the coordination of the unique microstructure.In this study,a hierarchical structure of Mg-15Gd-1Zn-0.4Zr(GZ151K)alloys containing grain,twin,and precipitation structural units was prepared by ultrasonic surface rolling process(USRP)and recrystallization annealing(RU).The results showed that the stress gradient generated by USRP formed a twin gradient structure,which will activate the twin-assisted precipitation(TAP)effect and twin-induced recrystallization(TIR)effect during RU.Then,the twin gradient structure transformed into a twin-precipitation gradient structure,and finally into a hierarchical structure with grain-twinprecipitation as the increasement of recrystallization degree.Besides,the dual gradient structure with twin and precipitation structural units had the highest strength and microhardness owing to the precipitation strengthening.However,the hierarchical structure with grain,twin,and precipitation structural units exhibited the most excellent combination of strength and plasticity under grain refinement and precipitation strengthening.
基金supported by the National Key R&D program of China(2023YFE0207000)the National Natural Science Foundation of China(Grant No.51975283 and U22B2040)the Research Fund of State Key Laboratory of Mechanics and Control for Aerospace Structures(Grant No.1005-IZD2300225).
文摘Flexible attachment actuators are popular in a wide range of applications,owing to their flexibility and highly reliable attachment.However,their reversible adhesion performance depends on the actual effective contact area and peel angle during operation.Therefore,a good actuator must ensure a uniform and reliable pre-pressure load on an adhesive surface,to increase the effective contact area of the attached surface,thereby maximizing adhesion.This study was inspired by fusion bionics for designing a hierarchical attachment structure with vacuum-adsorption and dry-adhesion mechanisms.The designed structure used the normal force under the negative pressure of a suction cup as a stable source of a pre-pressure load.By optimizing the rigid and flexible structural layers of the attachment structure,a load was applied uniformly to the adhesion area;thus,reliable attachment was achieved by self-preloading.The structure achieved detachment by exploiting the large deformation of a pneumatic structure under a positive pressure.The hierarchical attachment structure achieved up to 85%of the optimal performance of the adhesive surface.Owing to its self-preloading and reliable attachment characteristics,the designed structure can be used as an attachment unit in various complex scenarios,such as small,lightweight climbing platforms and the transport of objects in long,narrow pipelines.
文摘Some living organisms with hierarchical structures in nature have received extensive attention in various fields.The hierarchical structure with multiple pores,a large number of solid-gas interfaces and tortuous conduction paths provide a new direction for the development of thermal insulation materials,making the living creatures under these extreme conditions become the bionic objects of scientific researchers.In this review,the research progress of bionic hierarchical structure in the field of heat insulation is highlighted.Polar bears,cocoons,penguin feathers and wool are typical examples of heat preservation hierarchy in nature to introduce their morphological characteristics.At the same time,the thermal insulation mechanism,fractal model and several preparation methods of bionic hierarchical structures are emphatically discussed.The application of hierarchical structures in various fields,especially in thermal insulation and infrared thermal stealth,is summarised.Finally,the hierarchical structure is prospected.
基金financially supported by the National Natural Science Foundation of China(Grant Nos.52105303 and 52025053)Natural Science Foundation of Jilin Province(No.20220101209JC)Foundation for Innovative Research Groups of the National Natural Science Foundation of China(No.52021003).
文摘Amplifying the intrinsic wettability of substrate material by changing the solid/liquid contact area is considered to be the main mechanism for controlling the wettability of rough or structured surfaces.Through theoretical analysis and experimental exploration,we have found that in addition to this wettability structure amplification effect,the surface structure also simultaneously controls surface wettability by regulating the wetting state via changing the threshold Young angles of the Cassie-Baxter and Wenzel wetting regions.This wetting state regulation effect provides us with an alternative strategy to overcome the inherent limitation in surface chemistry by tailoring surface structure.The wetting state regulation effect created by multi-scale hierarchical structures is quite significant and plays is a crucial role in promoting the superhydrophobicity,superhydrophilicity and the transition between these two extreme wetting properties,as well as stabilizing the Cassie-Baxter superhydrophobic state on the fabricated lotus-like hierarchically structured Cu surface and the natural lotus leaf.
基金supported by the National Natural Science Foundation of China(Grant No.82372391,82001971,82102358,82202698,52105343,U21A2099 and U23A20523)Project of“Medical+X”interdisciplinary innovation team of Norman Bethune Health Science Center of Jilin University(Grant No.2022JBGS06)+5 种基金Project of youth interdisciplinary innovation team of Jilin University(Grant No.419070623054)China Postdoctoral Science Foundation(Grant No.2021M701384)Bethune Plan of Jilin University(Grant No.2022B27,2022B03)Wu Jieping Medical Foundation(Grant No.320.6750.18522)Scientific Development Program of Jilin Province(Grant No.20220402067GH)Jilin Province Development and Reform Commission(Grant No.2022C044-2).
文摘3D-printed Porous Titanium Alloy Implants(pTi),owing to their biologically inertness and relatively smooth surface morphology,adversely affect the biological functions of surrounding cells.To address the challenges,constructing a bioinspired interface that mimics the hierarchical structure of bone tissue can enhance the cellular functions of cells.In this context,Hollow Mesoporous Silica Nanoparticles(HMSNs),renowned for their unique physicochemical properties and superior biocompatibility,offer a promising direction for this research.In this research,the initially synthesized HMSNs were used to construct a“hollow-mesoporous-macroporous”hierarchical bioinspired coating on the pTi surface through the Layer-by-Layer technique.Simultaneously,diverse morphologies of coatings were established by adjusting the deposition strategy of PDDA/HMSNs on the pTi surface(pTi-HMSN-2,pTi-HMSN-4,pTi-HMSN-6).A range of techniques were employed to investigate the physicochemical properties and regulation of cellular biological functions of the diverse HMSN coating strategies.Notably,the pTi-HMSN-4 and pTi-HMSN-6 groups exhibited the uniform coatings,leading to a substantial enhancement in surface roughness and hydrophilicity.Meantime,the coating constructed strategy of pTi-HMSN-4 possessed commendable stability.Based on the aforementioned findings,both pTi-HMSN-4 and pTi-HMSN-6 facilitated the adhesion,spreading,and pseudopodia extension of BMSCs,which led to a notable upsurge in the expression levels of vinculin protein in BMSCs.Comprehensive analysis indicates that the coating,when PDDA/HMSNs are deposited four times,possesses favorable overall performance.The research will provide a solid theoretical basis for the translation of HMSN bioinspired coatings for orthopedic implants.
基金financially supported by the National Natural Science Foundation of China(No.12174092,21902046,U21A20500)Overseas Expertise Introduction Center for Discipline Innovation(D18025)+1 种基金Hubei Provincial Department of Science and Technology(No.2019CFA079)Wuhan Science and Technology Bureau(2020010601012163)
文摘Development of metal oxide semiconductors-based methane sensors with good response and low power consumption is one of the major challenges to realize the real-time monitoring of methane leakage.In this work,a self-assembled mulberry-like ZnO/SnO_(2)hierarchical structure is constructed by a two-step hydrothermal method.The resultant sensor works at room temperature with excellent response of~56.1%to 2000 ppm CH_(4)at 55%relative humidity.It is found that the strain induced at the ZnO/SnO_(2)interface greatly enhances the piezoelectric polarization on the ZnO surface and that the band bending results in the accumulation of chemically adsorbed O_(2)^(-)ions close to the interface,leading to significant improvement in the sensing performance of the methane gas sensor at room temperature.
基金supported by the National Natural Science Foundation of China (51320105001, 51372190, 21573170, 51272199, 21433007)the National Basic Research Program of China (973 program, 2013CB632402)+2 种基金the Natural Science Foundation of Hubei Province (2015CFA001)the Fundamental Research Funds for the Central Universities (WUT: 2015-Ⅲ-034)Innovative Research Funds of SKLWUT (2015-ZD-1)~~
文摘Flower-like tin oxide-supported platinum（Pt/SnOx） with a hierarchical structure was synthesized by a hydrothermal method and characterized by XRD,SEM,TEM,high resolution TEM,XPS and nitrogen adsorption.The flower-like Pt/SnOx microspheres of 1 μm in diameter were composed of staggered petal-like nanosheets with a thickness of 20 nm.Pt nanoparticles（NPs） of 2-3 nm were well dispersed on the SnOx nanosheets.The catalyst was tested in the catalytic oxidation of gaseous formaldehyde（HCHO） at room temperature,and exhibited enhanced activity compared to Pt NPs supported on commercial SnO and ground SnOx.HCHO removal of 87%was achieved over the hierarchical Pt/SnOx after 1 h of reaction,which was 1.5 times that over the ground SnOx-supported Pt（Pt/g-SnOx）,and the high activity was maintained after six recycles,showing the high stability of this catalyst.HCHO decomposition kinetics was modeled as a second order reaction.The reaction rate constant for Pt/SnOx was 5.6 times higher than Pt/g-SnOx.The hierarchical pore structure was beneficial for the diffusion and adsorption of HCHO molecules,and the highly dispersed Pt NPs on the SnOx nanosheets were the active sites for the oxidative decomposition of HCHO into CO2 and H2O.This study provided a promising approach for designing efficient catalysts for indoor HCHO removal at ambient temperature.
基金financial support from “13th five-year plan” equipment pre-research project of China (41422010501)。
文摘Based on the general [Mo] equivalent criterion and d-electron orbital theory, a new ultrahigh-strength βtitanium alloy with eight major elements(Ti-4.5Al-6.5Mo-2Cr-2.6Nb-2Zr-2Sn-1V, TB17) for industrial applications was developed. An ingot of five tons was successfully melted by thrice vacuum consumable arc melting. The microstructure and elements partitioning of different conditions were investigated systematically. The results suggest that the hierarchical structures of micro-scale first α phase(αf), nano-scale secondary α phase(αs), and ultrafine FCC substructures can be tailored by solution plus aging(STA) heat treatment. The lateral and epitaxial growth of αfphase promotes the HCP-α to FCC substructure transformation with the help of elements partitioning during the aging process. Moreover, the element V, generally regarded as β stabilizer, is found to mainly concentrate in the Al-rich αfphase in this study probably due to its relatively lower content and the strong bonding energy of Al-V. The hierarchical structure has a strong interaction with dislocations, which contributes to achieve a superhigh strength of 1376 MPa.In addition, the plastic strain is partitioned in the multi-scale precipitates(such as the α and FCC substructures) and β matrix, resulting in a considerable plasticity. TEM observation demonstrates that high density entangled dislocations at interfaces and mechanical twins exist in the STA sample after tensile test. It can be deduced that both dislocation slipping and twinning mechanisms are present in this alloy.Therefore, TB17 alloy can serve as an excellent candidate for structural materials on aircrafts that require high strength and lightweight.
基金the National Natural Science Foundation of China(51973157,51673148 and 51678411),Chinathe China Postdoctoral Science Foundation Grant(2019 M651047),Chinathe Science and Technology Plans of Tianjin(No.17PTSYJC00040 and 18PTSYJC00180),China for the financial support。
文摘The utilization of all-solid-state electrolytes is considered to be an effective way to enhance the safety performance of lithium metal batteries.However,the low ionic conductivity and poor interface compatibility greatly restrict the development of all-solid-state battery.In this study,a composite electrolyte combining the electrospun polyamide 6(PA6)nanofiber membrane with hierarchical structure and the polyethylene oxide(PEO)polymer is investigated.The introduction of PA6 nanofiber membrane can effectively reduce the crystallinity of the polymer,so that the ionic conductivity of the electrolyte can be enhanced.Moreover,it is found that the presence of finely branched fibers in the hierarchical structure PA6 membrane allows the polar functional groups(C=O and N-H bonds)to be fully exposed,which provides sufficient functional sites for lithium ion transport and helps to regulate the uniform deposition of lithium metal.Moreover,the hierarchical structure can enhance the mechanical strength(9.2 MPa)of the electrolyte,thereby effectively improving the safety and cycle stability of the battery.The prepared Li/Li symmetric battery can be stably cycled for 1500 h under 0.3 mA cm^(-2) and 60℃.This study demonstrates that the prepared electrolyte has excellent application prospects in the next generation all-solid-state lithium metal batteries.
基金The research was supported by the National Basic Research Program of China (Grant 2012CB937500),the National Natural Science Foundation of China (Grants 91216108,11432014),and the CAS/SAFEA International Partnership Program for Creative Reserch Teams
文摘In the present research, hierarchical structure observation and mechanical property characterization for a type of biomaterial are carried out. The investigated bioma- terial is Hyriopsis cumingii, a typical limnetic shell, which consists of two different structural layers, a prismatic ＂pillar＂ structure and a nacreous ＂brick and mortar＂ structure. The prismatic layer looks like a ＂pillar forest＂ with variationsection pillars sized on the order of several tens of microns. The nacreous material looks like a ＂brick wall＂ with bricks sized on the order of several microns. Both pillars and bricks are composed of nanoparticles. The mechanical properties of the hierarchical biomaterial are measured by using the nanoindentation test. Hardness and modulus are measured for both the nacre layer and the prismatic layer, respectively. The nanoindentation size effects for the hierarchical structural materials are investigated experimentally. The results show that the prismatic nanostructured material has a higher stiffness and hardness than the nacre nanostructured material. In addition, the nanoindentation size effects for the hierarchical structural materials are described theoretically, by using the trans-scale mechanics theory considering both strain gradient effect and the surface/interface effect. The modeling results are consistent with experimental ones.
基金financially supported by the Distinguished Taishan Scholars in Climbing Plan (No. tspd20161006)the Major-Special Science and Technology Projects in Shandong Province(Nos.2019JZZY010303 and 2019JZZY010360)Shandong Provincial Natural Science Foundation (No. ZR2019MEM049)。
文摘In this paper,a three-dimensional(3D)hierar-chical ZnO structure consisting of nanosheets modified with ultrafine NiO particles was synthesized via a facile two-step chemical precipitate method.Various techniques characterized the as-synthesized ZnO/NiO composites and pure ZnO.The p-NiO/n-ZnO junctions formed between adjacent ZnO and NiO nanoparticles,improving the gas sensing performance.The ZnO/NiO composite with the Ni:Zn atomic ratio of 7.42:100 exhibited the best iso-propanol sensing properties.Compared to pure ZnO,it showed high selectivity and sensitivity(R_(a)/R_(g)=221.3 toward 400×10^(-6)isopropanol),fast response rate(less than 10 s),short recovery time,and simultaneously low operating temperature.Also,the ZnO/NiO composite exhibited a wide sensing range(1×10^(-6)-1000×10^(-6))to isopropanol and processed good long-term stability.The experimental results suggested the potential application in fabricating efficient isopropanol sensors using this ZnO/NiO composite.The enhanced isopropanol sensing mech-anism is also discussed in charge transfer between heterojunctions,surface area,and surface defects.
基金the National Natural Science Foundation of China(Nos.51803102 and 51903129)Natural Science Foundation of Shandong Province(Nos.201807070028 and 201808220020)+2 种基金the Source Innovation Project of Qingdao(No.19-6-2-75-cg)Industry and Education Cooperation Program of The Ministry of Education(Nos.201802201002,201901078008 and 201802230009)Opening Project of Shanxi Province Key Laboratory of Functional Nanocomposites,North University of China(No.NFCM202001).
文摘In order to enhance the interfacial adhesion of carbon fiber(CF)and polymer matrix,a multiscale gradient modulus intermediate layer with rigid-flexible(GO-PA)hierarchical structure was designed and fabricated between CFs and matrix by a facile and businesslike strategy.The polarity,roughness and wettability of CFs surface as well as the thickness of intermediate layer in composite have been significantly increased after rigid-flexible hierarchical structure was constructed.The IFSS,ILSS,compression and impact toughness manifested that the hierarchical structure could bring about a fantastic improvement(76.8%,46.4%,40.7%and 37.8%)for the interfacial and mechanical properties than other previous reports.Consequently,the establishment of CF surface with gradient modulus rigid-flexible hierarchical structure via regulation of nanoparticles and polymer array would open a new,viable and promising route to obtaining high-performance composites.
基金supported by the National Natural Science Foundation of China(No.51772310)National Natural Science Foundation of China(No.52222202)+3 种基金Chinese Academy of Sciences Key Research Program of Frontier Sciences(No.QYZDYSSWJSC031)Key Deployment Projects of the Chinese Academy of Sciences(No.ZDRW-CN2019-01)Shanghai Sailing Program(No.21YF1454600)Outstanding Chinese and Foreign Youth Exchange Program of China Association of Science and Technology.
文摘In this work,hierarchical hybrid composites consisting of porous three-dimensional reduced graphene oxide(3D-rGO)skeleton and lamellar boron nitride(BN)/silicon carbide(SiC)coatings are prepared by chemical vapor infiltration(CVI)process.The graphene framework prepared by 3D printing and frozen self-assembly exhibits a lightweight structure and a perforated conductive network,which extends the transmission path of incident microwaves.The introduced ceramic coatings can effectively tune the impedance matching degree and supply a lossy phase,and the hierarchical structure of the composites enhances the multiple scattering of the incident microwaves.As expected,the 3D-rGO/BN/SiC composites possess an excellent absorbing performance with a minimum reflection loss value of–37.8 dB,and the widest effective absorbing bandwidth(RL<–10 dB)of 5.90 GHz is obtained.The controllable fabrication of composites can provide a guideline for rational design and fabrication of high-performance electromagnetic waves absorbing materials in practical applications.
基金Project supported by the National Science Centre of Poland by the SONATA 11 project UMO-2016/21/D/ST3/00962
文摘In this work the flower-like hierarchical structures(HS) based on 3 D pristine ZnO,ZnO:Eu^3+ and ZnO:Eu^3+ @Au were successfully obtained by a template-free solvothermal and deposition-precipitation method.The decolorization/photodegradation of these structures towards model organic dye(rhodamine 6 G) was studied.The synthesized ZnO-based HS were characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM),UV-vis and photoluminescence(PL) spectroscopies.The proposed synthesis approaches allow to obtain highly crystalline 3 D ZnO,ZnO:Eu^3+ and ZnO:Eu^3+ @Au composites.Results of scanning microscopy show that ZnO flower-like HS are assemblies from smaller components,forming larger ones,the whole ZnO structure was approximately 3 μm.Au nanoparticles(size^10 nm)are successfully deposited on ZnO HS surface.Luminescent studies show that ZnO is an ideal matrix for incorporation of Eu^3+ ions in broad concentration range(Eu^3+=1.0 at%-5.0 at%) with an efficient red luminescence.The strong UV emission in ZnO,as well as ZnO;Eu^3+HS is observed under 325 nm excitation.Doping of ZnO HS matrix by Eu^3+ions leads to the red shift of deep level emission peak(DLE).The PL intensity reaches the maximum up to 5 at% Eu^3+.The photocatalytic properties of ZnO and ZnO:Eu^3+ @Au HS were investigated under UV-Vis light irradiation towards rhodamine 6 G.The obtained results demonstrate the synergetic effect of the deposited gold nanoparticles and Eu3^+ doping on photocatalytic activity of ZnO:Eu^3+@Au HS in comparison to pristine ZnO and ZnO:Eu^3+ HS.
基金The authors are grateful to the financial support of the National Natural Science Foundation of China(32071702)Beijing Forestry University Outstanding Young Talent Cultivation Project(2019JQ03004).
文摘Soy protein-based composite film is a potential replacement for petroleum-based film with multipurpose applica-tions and cleaner production.It is difficult to improve both the tensile strength and toughness of a protein-based film without sacrificing its elongation.In this study,inspired by the hierarchical structure of nacre,a facile yet delicate strategy was developed to fabricate a novel bio-based film with excellent toughness and high strength.Triglycidylamine(TGA)crosslinked soy protein(SPI)as hard phase and thermoplastic polyurethane elastomer(TPU)as soft phase comprise an alternative lay-up hierarchical structure.The interface of these two phases is enhanced using triglycidylamine(TGA)surface-modified TPU(MTPU).The tensile strength of SPI/MTPU/TGA films increases by 392%to 7.78 MPa and their toughness increases by 391%to 8.50 MJ/m^(3) compared to soy protein/glycerol film.The proposed hierarchical structure can also be extended to other high-performance materials and polymers.
基金supported by the National Basic Research Program of China (973 Program,2010CB125900 and 2004CB117203)the National Key Technologies R&D Program during the 11th Five-Year-Plan period (2006BAD13B05)+1 种基金the National Natural Science Foundation of China (30490251 and30471096)the Academy and Institute Foundation for Basic Scientific Research in Institute of Crop Sciences,Chinese Academy of Agricultural Sciences
文摘For clarifying the hierarchical patterns of population structure of soybean landraces in China, the seven clusters previously identified using Bayesian clustering of 1 504 soybean landraces based on SSR markers genotyping data were further analyzed. Using the largest value of AK, these landraces could be split into 20 sub-clusters, which was supported by highly significant pairwise Fst-values and generally in accordance with the geographic origin and sowing types. The autumn-sowing types ended up in one distinct sub-cluster from the otherwise summer-sowing type, where the autumn- sowing types are most likely derived from. The division into 20 sub-clusters explained 7.3% of the genetic variation, next to 9.7% present among the seven clusters, 81.1% residing among landraces within sub-clusters, and 1.9% within the landraces. The distribution pattern of genetic diversity among the sub-clusters of each cluster was uneven, with two HSuM sub-clusters （Central China） and some South China sub-clusters showing significantly higher level of genetic diversity.
文摘ZnO nanosheets and nanoflakes were grown on alumina particles in the absence of surfactants via heterogeneous precipitation using urea, zinc acetate and bayerite as precursors. Thermo-gravimetric analysis （TGA）, X-ray diffraction （XRD） and Fourier transform infrared spectroscopy （FTIR） were used and the results indicated the formation of only two phases： wurtzite-type ZnO and γ-Al2O3. ZnO nanoflakes were grown on alumina particles in the samples with ZnO content of 40 and 60 wt%, By increasing the ZnO content to 80 wt%, a porous hierarchical structure of ZnO with nanosheet arrays appeared. Both of these nanoflakes and nanosheets were about 40-80 nm in thickness and about 1-2 μm in diameter. It was proposed that Zns（CO3）2（OH）6 nuclei undergo higher growth rates in thin sheets at edges of bayerite particles with a higher surface energy. The Brunauer-Emmett-Teller （BET） measurements proved a reachable high surface area for hierarchical structures of ZnO nanosheets, which could mainly be attributed to their unique growth on alumina particles. Also, UV absorption results revealed that ZnO--Al2O3 compositions still show the UV characteristic absorption of ZnO, which can evidence the presence of photocatalytic properties in ZnO-Al2O3 compositions.
基金Project supported by the Natural Science Foundation of Anhui Province, China （Grant No, 12010202035） and the National Natural Science Foundation of China （Grant No. 51272246）.
文摘Wettability and the light-trapping effect of FeSe2 particles with a micro-nano hierarchical structure have been inves- tigated. Particles are synthesized by an improved solvothermal method, wherein hexadecyl trimetbyl ammonium bromide （CTAB） is employed as a surfactant. After modifying the particles with heptadecafluorodecyltrimethoxy-silane （HTMS）, we find that the water contact angle （WCA） of the FeSe2 particles increases by 6.1~ and the water sliding angle （WSA） decreases by 2.5~ respectively, and the diffuse reflectivity decreases 29.4% compared with similar FeSe2 particles synthe- sized by the conventional method. The growth process of the particles is analyzed and a growth scenario is given. Upon altering the PH values of the water, we observe that the superhydrophobic property is maintained quite consistently across a wide PH range of 1-14. Moreover, the modified particles were also found to be superoleophobic. To the best of our knowledge, there is no systematic research on the wettability of FeSe2 particles, so our research provides a reference for other researchers.
