Zinc oxide(ZnO)serves as a crucial functional semiconductor with a wide direct bandgap of approximately 3.37 eV.Solvothermal reaction is commonly used in the synthesis of ZnO micro/nanostructures,given its low cost,si...Zinc oxide(ZnO)serves as a crucial functional semiconductor with a wide direct bandgap of approximately 3.37 eV.Solvothermal reaction is commonly used in the synthesis of ZnO micro/nanostructures,given its low cost,simplicity,and easy implementation.Moreover,ZnO morphology engineering has become desirable through the alteration of minor conditions in the reaction process,particularly at room temperature.In this work,ZnO micro/nanostructures were synthesized in a solution by varying the amounts of the ammonia added at low temperatures(including room temperature).The formation of Zn^(2+)complexes by ammonia in the precursor regulated the reaction rate of the morphology engineering of ZnO,which resulted in various structures,such as nanoparticles,nanosheets,microflowers,and single crystals.Finally,the obtained ZnO was used in the optoelectronic application of ultraviolet detectors.展开更多
Urea-assisted water electrolysis offers a promising route to reduce energy consumption for hydrogen production and meanwhile treat urea-rich wastewater.Herein,we devised a shear force-involved polyoxometalate-organic ...Urea-assisted water electrolysis offers a promising route to reduce energy consumption for hydrogen production and meanwhile treat urea-rich wastewater.Herein,we devised a shear force-involved polyoxometalate-organic supramolecular self-assembly strategy to fabricate 3D hierarchical porous nanoribbon assembly Mn-VN cardoons.A bimetallic polyoxovanadate(POV)with the inherent structural feature of Mn surrounded by[VO_(6)]octahedrons was introduced to trigger precise Mn incorporation in VN lattice,thereby achieving simultaneous morphology engineering and electronic structure modulation.The lattice contraction of VN caused by Mn incorporation drives electron redistribution.The unique hierarchical architecture with modulated electronic structure that provides more exposed active sites,facilitates mass and charge transfer,and optimizes the associated adsorption behavior.Mn-VN exhibits excellent activity with low overpotentials of 86 m V and 1.346 V at 10 m A/cm^(2)for hydrogen evolution reaction(HER)and urea oxidation reaction(UOR),respectively.Accordingly,in the two-electrode urea-assisted water electrolyzer utilizing Mn-VN as a bifunctional catalyst,hydrogen production can occur at low voltage(1.456 V@10 m A/cm^(2)),which has the advantages of energy saving and competitive durability over traditional water electrolysis.This work provides a simple and mild route to construct nanostructures and modulate electronic structure for designing high-efficiency electrocatalysts.展开更多
Two-dimensional covalent organic frameworks(COFs)with specific morphologies including nanofibers and nanoplates are highly desired in both nanoscience research and practical applications.Thus far,however,morphology en...Two-dimensional covalent organic frameworks(COFs)with specific morphologies including nanofibers and nanoplates are highly desired in both nanoscience research and practical applications.Thus far,however,morphology engineering for COFs remains challenging because the mechanism underlying the morphology formation and evolution of COFs is not well understood.Herein,we propose a strategy of surfactant mediation coupled with acid adjustment to engineer the morphology of aβ-ketoenamine-linked COF,TpPa,during solvothermal synthesis.The surfactants function as stabilizers that can encapsulate monomers and prepolymers to create micelles,enabling the formation of fiber-like and plate-like morphologies of TpPa rather than irregularly shaped aggregates.It is also found that acetic acid is important in regulating such morphologies,as the amino groups inside the prepolymers can be precisely protonated by acid adjustment,leading to an inhibited ripening process for the creation of specific morphologies.Benefitting from the synergistic enhancement of surfactant mediation and acid adjustment,TpPa nanofibers with a diameter down to~20 nm along with a length of up to a few microns and TpPa nanoplates with a thickness of~18 nm are created.Our work sheds light on the mechanism underlying the morphology formation and evolution of TpPa,providing some guidance for exquisite control over the growth of COFs,which is of great significance for their practical applications.展开更多
Understanding the microstructure-property relationship from the microscopic and macroscopic perspectives,instead of semi-empirical rules,can facilitate the design of microcosmic morphology to adjust the impedance matc...Understanding the microstructure-property relationship from the microscopic and macroscopic perspectives,instead of semi-empirical rules,can facilitate the design of microcosmic morphology to adjust the impedance matching and dielectric loss of the carbon-based materials,which are still lacking so far.In this study,a clear correlation between microstructure and conduction loss was revealed in agarosederived carbon using a facile salt-etching strategy,in which ferric nitrate acted more as a morphology modifier for bulky carbon rather than a component regulator.Specifically,with the increasing amount of ferric nitrate,the original smooth bulky carbon was etched with caves,which gradually enlarged in size and depth and thus thinned in wall,and eventually transformed into a three-dimensional(3D)interconnected cellular structure,accompanied by a gradual increase in conductivity.Benefiting from the optimal impedance matching and strong conduction loss originating from the unique 3D cellular structure of agarose-derived carbon,AF-3 exhibited super-wide and strong absorption with an effective absorption bandwidth of 7.28 GHz(10.32-17.60 GHz,2.9 mm)and a minimum reflection loss of-46.6 dB(15.6 GHz,2.5 mm).This study establishes the relationship between microstructure,dielectric properties,and loss mechanism in carbon-based materials and also provides a new insight into the fine modulation of EMW-absorbing properties from morphological design.展开更多
The incorporation of small vip molecules or ions by bottom-up hydrothermal synthesis has recently emerged as a promising new way to engineer 1T-phase MoS2 with high hydrogen evolution reaction （HER） activity. Howe...The incorporation of small vip molecules or ions by bottom-up hydrothermal synthesis has recently emerged as a promising new way to engineer 1T-phase MoS2 with high hydrogen evolution reaction （HER） activity. However, the mechanism of the associated structural evolution remains elusive and controversial, leading to a lack of effective routes to prepare 1T-phase MoS2 with controlled structure and morphology, along with high purity and stability. Herein, urea is chosen as precursor of small molecules or ions to simultaneously engineer the phase （16.4%, - 69.4%, and -90.2% of 1T phase） and size （98.8, - 151.6, and - 251.8 nm for the 90.2% 1T phase） of MoS2 nanosheets, which represent an ideal model system for investigating the structural evolution in these materials, as well as developing a new type of 1T-phase MoS2 arrays. Using reaction intermediate monitoring and theoretical calculations, we show that the oriented growth of 1T-phase MoS2 is controlled by ammonia-assisted assembly recrystallization, and stabilization processes. A superior HER performance in acidic media is obtained, with an overpotential of only 76 mV required to achieve a stable current density of 10 mA.cm-2 for 15 h. This excellent performance is attributed to the unique array structure, involving well-dispersed, edge-terminated, and high-purity 1T-phase MoS2 nanosheets.展开更多
Microbial morphology engineering is a novel approach for cell factory to improve the titer of target product in bio-manufacture.Hyaluronic acid(HA),a valuable glycosaminoglycan polymerized by HA synthase(HAS),a membra...Microbial morphology engineering is a novel approach for cell factory to improve the titer of target product in bio-manufacture.Hyaluronic acid(HA),a valuable glycosaminoglycan polymerized by HA synthase(HAS),a membrane protein,is particularly selected as the model product to improve its single-cell HA-producing capacity via morphology engineering.DivIVA and FtsZ,the cell-elongation and cell division related protein,respectively,were both down/up dual regulated in C.glutamicum via weak promoter substitution or plasmid overexpression.Different from the natural short-rod shape,varied morphologies of engineered cells,i.e.small-ellipsoid-like(DivIVA-reduced),bulb-like(DivIVA-enhanced),long-rod(FtsZ-reduced)and dumbbell-like(FtsZ-enhanced),were observed.Applying these morphology-changed cells as hosts for HA production,the reduced expression of both DivIVA and FtsZ seriously inhibited normal cell growth;meanwhile,overexpression of DivIVA didn't show morphology changes,but overexpression of FtsZ surprisingly change the cell-shape into long and thick rod with remarkably enlarged single-cell surface area(more than 5.2-fold-increase).And finally,the single-cell HA-producing capacity of the FtsZ-overexpressed C.glutamicum was immensely improved by 13.5-folds.Flow cytometry analyses verified that the single-cell HAS amount on membrane was enhanced by 2.1 folds.This work is pretty valuable for high titer synthesis of diverse metabolic products with microbial cell factory.展开更多
Vanadium dioxide(VO_(2)) with the advantages of high theoretical capacity and tunnel structure has attracted considerable promising candidates for aqueous zinc-ion batteries.Nevertheless,the intrinsic low electronic c...Vanadium dioxide(VO_(2)) with the advantages of high theoretical capacity and tunnel structure has attracted considerable promising candidates for aqueous zinc-ion batteries.Nevertheless,the intrinsic low electronic conductivity of VO_(2) results in an unsatisfactory electrochemical performance.Herein,a flower-like VO_(2)/carbon nanotubes(CNTs)composite was obtained by a facile hydrothermal method.The unique flower-like morphology shortens the ion transport length and facilitates electrolyte infiltration.Meanwhile,the CNT conductive networks is in favor of fast electron transfer.A highly reversible zinc storage mechanism was revealed by ex-situ X-ray diffraction and X-ray photoelectron spectroscopy.As a result,the VO_(2)/CNTs cathode exhibits a high reversible capacity(410 mAh·g^(−1)),superior rate performance(305 mAh·g^(−1)at 5 A·g^(−1)),and excellent cycling stability(a reversible capacity of 221 mAh·g^(−1)was maintained even after 2000 cycles).This work provides a guide for the design of high-performance cathode materials for aqueous zinc metal batteries.展开更多
In recent years,photocatalysis(PC)and photoelectrocatalysis(PEC)technologies have shown great promise as low-cost,environmentally friendly,and sustainable strategies in addressing the issues of energy shortages and en...In recent years,photocatalysis(PC)and photoelectrocatalysis(PEC)technologies have shown great promise as low-cost,environmentally friendly,and sustainable strategies in addressing the issues of energy shortages and environmental pollution,which has become a research hotspot.Titanium dioxide(TiO_(2))-based PC and PEC are the most promising sustainable technologies for advanced oxidation applications.Due to its inherent characteristics,including high oxidation ability,low price,and stability,TiO_(2)photocatalyst has been widely studied and used in different scales for numerous decades.For practical applications in these areas,the engineering of the photocatalysts and the design of the PC and PEC devices must be both environmentally and economically sustainable.On the one hand,for the engineering of the photocatalysts,the photocatalyst shall be able to deliver the following characteristics,including large specific surface area,high absorption of light,rapid and low-cost separation and regeneration,and high stability.On the other hand,the design of the PC and PEC devices shall facilitate high in energy utilization and catalytic efficiency,and low in building and operational cost.This work covers the reaction mechanism of TiO_(2)-based PC and PEC technologies,sustainable design,and preparation of TiO_(2)photocatalysts as well as sustainable design in PC and PEC devices for wastewater treatment,sensing,and water splitting.Finally,we provide some critical perspectives on the future development of TiO_(2)-based PC and PEC technology.展开更多
As an indispensable branch of wearable electronics,flexible pressure sensors are gaining tremendous attention due to their extensive applications in health monitoring,human-machine interaction,artificial intelligence,...As an indispensable branch of wearable electronics,flexible pressure sensors are gaining tremendous attention due to their extensive applications in health monitoring,human-machine interaction,artificial intelligence,the internet of things,and other fields.In recent years,highly flexible and wearable pressure sensors have been developed using various materials/structures and transduction mechanisms.Morphological engineering of sensing materials at the nanometer and micrometer scales is crucial to obtaining superior sensor performance.This review focuses on the rapid development of morphological engineering technologies for flexible pressure sensors.We discuss different architectures and morphological designs of sensing materials to achieve high performance,including high sensitivity,broad working range,stable sensing,low hysteresis,high transparency,and directional or selective sensing.Additionally,the general fabrication techniques are summarized,including self-assembly,patterning,and auxiliary synthesis methods.Furthermore,we present the emerging applications of high-performing microengineered pressure sensors in healthcare,smart homes,digital sports,security monitoring,and machine learning-enabled computational sensing platform.Finally,the potential challenges and prospects for the future developments of pressure sensors are discussed comprehensively.展开更多
Polyhydroxyalkanoates(PHA)have been produced by some bacteria as bioplastics for many years.Yet their commercialization is still on the way.A few issues are related to the difficulty of PHA commercialization:namely,hi...Polyhydroxyalkanoates(PHA)have been produced by some bacteria as bioplastics for many years.Yet their commercialization is still on the way.A few issues are related to the difficulty of PHA commercialization:namely,high cost and instabilities on molecular weights(Mw)and structures,thus instability on thermo-mechanical properties.The high cost is the result of complicated bioprocessing associated with sterilization,low conversion of carbon substrates to PHA products,and slow growth of microorganisms as well as difficulty of downstream separation.Future engineering on PHA producing microorganisms should be focused on contamination resistant bacteria especially extremophiles,developments of engineering approaches for the extremophiles,increase on carbon substrates to PHA conversion and controlling Mw of PHA.The concept proof studies could still be conducted on E.coli or Pseudomonas spp.that are easily used for molecular manipulations.In this review,we will use E.coli and halophiles as examples to show how to engineer bacteria for enhanced PHA biosynthesis and for increasing PHA competitiveness.展开更多
The photocatalytic efficiency of lead-free Bi-based halide perovskites,such as Cs_(3)Bi_(2)X_(9)(X=Br,I)for CO_(2)reduction is often hindered by self-aggregation and insufficient oxidation ability.In this work,a visib...The photocatalytic efficiency of lead-free Bi-based halide perovskites,such as Cs_(3)Bi_(2)X_(9)(X=Br,I)for CO_(2)reduction is often hindered by self-aggregation and insufficient oxidation ability.In this work,a visible-light-driven(λ>420 nm)Z-scheme heterojunction photocatalyst composed of 0D Cs_(3)Bi_(2)I_(9) nanoparticles on 1D WO_(3) nanorods for photocatalytic CO_(2)reduction and water oxidation is synthesized using an in situ growing approach.The resulting 0D/1D Cs_(3)Bi_(2)I_(9)/WO_(3) Z-scheme heterojunction photocatalyst exhibits a visible-light-driven photocatalytic CO_(2)reduction performance for selective CO production,achieving a selectivity of 98.7%and a high rate of 16.5µmol/(g·h),approximately three times that of pristine Cs_(3)Bi_(2)I_(9).Furthermore,it demonstrates decent stability in the gas-solid photocatalytic CO_(2)reduction system.The improved performance of Cs_(3)Bi_(2)I_(9)/WO_(3) is attributed to the formation of the 0D/1D Z-scheme heterojunction,which facilitates charge transfer,reduces charge recombination,and maintains the active sites of both 0D Cs_(3)Bi_(2)I_(9) for CO_(2)reduction and 1D WO_(3) for water oxidation.This work provides valuable insights into the potential of morphological engineering and the design of simultaneous Z-scheme heterojunction for lead-free halide perovskites.展开更多
Halide perovskites have attracted great attention due to their high color purity, high luminance yield, low non-radiative recombination rate, and solution processability. Although the external quantum efficiency of pe...Halide perovskites have attracted great attention due to their high color purity, high luminance yield, low non-radiative recombination rate, and solution processability. Although the external quantum efficiency of perovskite light-emitting diodes(Pe LEDs) is comparable with that of the organic light-emitting diodes(OLEDs) and quantum-dots light-emitting diodes(QLEDs), the brightness is still low compared with the traditional OLEDs and QLEDs. Herein, we demonstrate high brightness and high-efficiency Cs Pb Br3-based Pe LEDs using interface and bulk controlled nanocrystal growth of the perovskite emission layer. The interface engineering by ethanolamine and bulk engineering by polyethylene glycol led to highly crystallized and cubic-shaped perovskite nanocrystals with smooth and compact morphology. As a result, Pe LEDs with a high brightness of 64756 cd/m2 and an external quantum efficiency of 13.4% have been achieved.展开更多
Hierarchical tin（Ⅲ） oxide, Sn3O4, nanospheres were synthesized via hydrothermal reaction under strongly acidic ambient conditions. The morphology of Sn3O4 varied with decreasing pH. The prickly SnaO4 nanospheres ch...Hierarchical tin（Ⅲ） oxide, Sn3O4, nanospheres were synthesized via hydrothermal reaction under strongly acidic ambient conditions. The morphology of Sn3O4 varied with decreasing pH. The prickly SnaO4 nanospheres changed into SnaO4 nanospheres covered with single-crystalline nanoplates having a high BET surface area of ca. 55.05 m^2·g^-1 and a band gap of ca. 2.25 eV. Small amounts （0.05 g） of the hierarchical Sn3O4 nanostructures completely decomposed a 30% methyl orange （MO） solution in 100 mL deionized water within 15 min under one sun condition （UV ＋ visible light）. The Sn3O4 photocatalyst exhibited a fast decomposition rate of 1.73 ×10^-1 min^-1, which is a 90.86% enhancement relative to that of the commercially available P25 photocatalyst. The high photocatalytic activity of the hierarchical Sn3O4 nanostructures is attributed to its ability to absorb visible light and its high surface-to-volume ratio.展开更多
Two-dimensional(2D)magnetic crystals with intrinsic ferromagnetism are highly desirable for novel spin-electronic devices.However,the controllable synthesis of 2D magnets,especially the direct growth of 2D magnets on ...Two-dimensional(2D)magnetic crystals with intrinsic ferromagnetism are highly desirable for novel spin-electronic devices.However,the controllable synthesis of 2D magnets,especially the direct growth of 2D magnets on substrate surfaces,is still a challenge.Here,we demonstrate the synthesis of ultrathin zinc-blende phase manganese selenide(β-MnSe)nanosheets using the chemical vapor deposition(CVD)technique.The 2Dβ-MnSe crystals exhibit distinct ferromagnetic properties with a Curie temperature of 42.3 K.Density functional theory(DFT)calculations suggest that the ferromagnetic order inβ-MnSe originates from the exchange coupling between the unsaturated Se and Mn atoms.This study presents significant progress in the CVD growth of ultrathin 2D magnetic materials by thinning bulk magnets,and it will pave the way for the building of energy-efficient spintronic devices in the future.展开更多
基金funded by the National Natural Science F oundation of China(No.52172205)。
文摘Zinc oxide(ZnO)serves as a crucial functional semiconductor with a wide direct bandgap of approximately 3.37 eV.Solvothermal reaction is commonly used in the synthesis of ZnO micro/nanostructures,given its low cost,simplicity,and easy implementation.Moreover,ZnO morphology engineering has become desirable through the alteration of minor conditions in the reaction process,particularly at room temperature.In this work,ZnO micro/nanostructures were synthesized in a solution by varying the amounts of the ammonia added at low temperatures(including room temperature).The formation of Zn^(2+)complexes by ammonia in the precursor regulated the reaction rate of the morphology engineering of ZnO,which resulted in various structures,such as nanoparticles,nanosheets,microflowers,and single crystals.Finally,the obtained ZnO was used in the optoelectronic application of ultraviolet detectors.
基金supported by the National Natural Science Foundation of China(Nos.22322104,22171074)the Natural Science Foundation of Heilongjiang Province(No.YQ2021B009)+3 种基金the Reform and Development Fund Project of Local University supported by the Central Government(Outstanding Youth Program)Heilongjiang Province Young Scientific and Technological Talent Lifting Project(No.2023QNTJ019)the Basic Research Support Project for Outstanding Young Teachers in Heilongjiang Provincial University(No.YQJH2023129)the Outstanding Youth Science Foundation of Heilongjiang University(No.JCL202301)。
文摘Urea-assisted water electrolysis offers a promising route to reduce energy consumption for hydrogen production and meanwhile treat urea-rich wastewater.Herein,we devised a shear force-involved polyoxometalate-organic supramolecular self-assembly strategy to fabricate 3D hierarchical porous nanoribbon assembly Mn-VN cardoons.A bimetallic polyoxovanadate(POV)with the inherent structural feature of Mn surrounded by[VO_(6)]octahedrons was introduced to trigger precise Mn incorporation in VN lattice,thereby achieving simultaneous morphology engineering and electronic structure modulation.The lattice contraction of VN caused by Mn incorporation drives electron redistribution.The unique hierarchical architecture with modulated electronic structure that provides more exposed active sites,facilitates mass and charge transfer,and optimizes the associated adsorption behavior.Mn-VN exhibits excellent activity with low overpotentials of 86 m V and 1.346 V at 10 m A/cm^(2)for hydrogen evolution reaction(HER)and urea oxidation reaction(UOR),respectively.Accordingly,in the two-electrode urea-assisted water electrolyzer utilizing Mn-VN as a bifunctional catalyst,hydrogen production can occur at low voltage(1.456 V@10 m A/cm^(2)),which has the advantages of energy saving and competitive durability over traditional water electrolysis.This work provides a simple and mild route to construct nanostructures and modulate electronic structure for designing high-efficiency electrocatalysts.
基金the National Natural Science Foundation of China(No.21921006).
文摘Two-dimensional covalent organic frameworks(COFs)with specific morphologies including nanofibers and nanoplates are highly desired in both nanoscience research and practical applications.Thus far,however,morphology engineering for COFs remains challenging because the mechanism underlying the morphology formation and evolution of COFs is not well understood.Herein,we propose a strategy of surfactant mediation coupled with acid adjustment to engineer the morphology of aβ-ketoenamine-linked COF,TpPa,during solvothermal synthesis.The surfactants function as stabilizers that can encapsulate monomers and prepolymers to create micelles,enabling the formation of fiber-like and plate-like morphologies of TpPa rather than irregularly shaped aggregates.It is also found that acetic acid is important in regulating such morphologies,as the amino groups inside the prepolymers can be precisely protonated by acid adjustment,leading to an inhibited ripening process for the creation of specific morphologies.Benefitting from the synergistic enhancement of surfactant mediation and acid adjustment,TpPa nanofibers with a diameter down to~20 nm along with a length of up to a few microns and TpPa nanoplates with a thickness of~18 nm are created.Our work sheds light on the mechanism underlying the morphology formation and evolution of TpPa,providing some guidance for exquisite control over the growth of COFs,which is of great significance for their practical applications.
基金supported by the National Natural Science Foundation of China(No.52362024 and 22004106).
文摘Understanding the microstructure-property relationship from the microscopic and macroscopic perspectives,instead of semi-empirical rules,can facilitate the design of microcosmic morphology to adjust the impedance matching and dielectric loss of the carbon-based materials,which are still lacking so far.In this study,a clear correlation between microstructure and conduction loss was revealed in agarosederived carbon using a facile salt-etching strategy,in which ferric nitrate acted more as a morphology modifier for bulky carbon rather than a component regulator.Specifically,with the increasing amount of ferric nitrate,the original smooth bulky carbon was etched with caves,which gradually enlarged in size and depth and thus thinned in wall,and eventually transformed into a three-dimensional(3D)interconnected cellular structure,accompanied by a gradual increase in conductivity.Benefiting from the optimal impedance matching and strong conduction loss originating from the unique 3D cellular structure of agarose-derived carbon,AF-3 exhibited super-wide and strong absorption with an effective absorption bandwidth of 7.28 GHz(10.32-17.60 GHz,2.9 mm)and a minimum reflection loss of-46.6 dB(15.6 GHz,2.5 mm).This study establishes the relationship between microstructure,dielectric properties,and loss mechanism in carbon-based materials and also provides a new insight into the fine modulation of EMW-absorbing properties from morphological design.
文摘The incorporation of small vip molecules or ions by bottom-up hydrothermal synthesis has recently emerged as a promising new way to engineer 1T-phase MoS2 with high hydrogen evolution reaction （HER） activity. However, the mechanism of the associated structural evolution remains elusive and controversial, leading to a lack of effective routes to prepare 1T-phase MoS2 with controlled structure and morphology, along with high purity and stability. Herein, urea is chosen as precursor of small molecules or ions to simultaneously engineer the phase （16.4%, - 69.4%, and -90.2% of 1T phase） and size （98.8, - 151.6, and - 251.8 nm for the 90.2% 1T phase） of MoS2 nanosheets, which represent an ideal model system for investigating the structural evolution in these materials, as well as developing a new type of 1T-phase MoS2 arrays. Using reaction intermediate monitoring and theoretical calculations, we show that the oriented growth of 1T-phase MoS2 is controlled by ammonia-assisted assembly recrystallization, and stabilization processes. A superior HER performance in acidic media is obtained, with an overpotential of only 76 mV required to achieve a stable current density of 10 mA.cm-2 for 15 h. This excellent performance is attributed to the unique array structure, involving well-dispersed, edge-terminated, and high-purity 1T-phase MoS2 nanosheets.
基金This work was supported by National Key R&D Program of China[2018YFA0902200]the National Natural Science Foundation of China[No.21776157].
文摘Microbial morphology engineering is a novel approach for cell factory to improve the titer of target product in bio-manufacture.Hyaluronic acid(HA),a valuable glycosaminoglycan polymerized by HA synthase(HAS),a membrane protein,is particularly selected as the model product to improve its single-cell HA-producing capacity via morphology engineering.DivIVA and FtsZ,the cell-elongation and cell division related protein,respectively,were both down/up dual regulated in C.glutamicum via weak promoter substitution or plasmid overexpression.Different from the natural short-rod shape,varied morphologies of engineered cells,i.e.small-ellipsoid-like(DivIVA-reduced),bulb-like(DivIVA-enhanced),long-rod(FtsZ-reduced)and dumbbell-like(FtsZ-enhanced),were observed.Applying these morphology-changed cells as hosts for HA production,the reduced expression of both DivIVA and FtsZ seriously inhibited normal cell growth;meanwhile,overexpression of DivIVA didn't show morphology changes,but overexpression of FtsZ surprisingly change the cell-shape into long and thick rod with remarkably enlarged single-cell surface area(more than 5.2-fold-increase).And finally,the single-cell HA-producing capacity of the FtsZ-overexpressed C.glutamicum was immensely improved by 13.5-folds.Flow cytometry analyses verified that the single-cell HAS amount on membrane was enhanced by 2.1 folds.This work is pretty valuable for high titer synthesis of diverse metabolic products with microbial cell factory.
基金supported by the National Natural Science Foundation of China(Nos.22209140 and 52202286)Natural Science Foundation of Shandong Province(No.ZR2022QE059)+3 种基金Shandong Laboratory of Advanced Materials and Green Manufacturing at Yantai(Yantai)(No.AMGM2023A08)Natural Science Foundation of Zhejiang Province(Nos.LGG23B030011 and LY24B030006)Scientific Research Fund of Zhejiang Provincial Education Department(No.Y202148249)Basic Research Project of Wenzhou City(No.G20220016).
文摘Vanadium dioxide(VO_(2)) with the advantages of high theoretical capacity and tunnel structure has attracted considerable promising candidates for aqueous zinc-ion batteries.Nevertheless,the intrinsic low electronic conductivity of VO_(2) results in an unsatisfactory electrochemical performance.Herein,a flower-like VO_(2)/carbon nanotubes(CNTs)composite was obtained by a facile hydrothermal method.The unique flower-like morphology shortens the ion transport length and facilitates electrolyte infiltration.Meanwhile,the CNT conductive networks is in favor of fast electron transfer.A highly reversible zinc storage mechanism was revealed by ex-situ X-ray diffraction and X-ray photoelectron spectroscopy.As a result,the VO_(2)/CNTs cathode exhibits a high reversible capacity(410 mAh·g^(−1)),superior rate performance(305 mAh·g^(−1)at 5 A·g^(−1)),and excellent cycling stability(a reversible capacity of 221 mAh·g^(−1)was maintained even after 2000 cycles).This work provides a guide for the design of high-performance cathode materials for aqueous zinc metal batteries.
基金Ph.D.scholarship,Griffith University,Australia,the Natural Science Foundation of Guangdong Province(No.2019A1515011138,2017A030313090)the 111 Project(D20015),China。
文摘In recent years,photocatalysis(PC)and photoelectrocatalysis(PEC)technologies have shown great promise as low-cost,environmentally friendly,and sustainable strategies in addressing the issues of energy shortages and environmental pollution,which has become a research hotspot.Titanium dioxide(TiO_(2))-based PC and PEC are the most promising sustainable technologies for advanced oxidation applications.Due to its inherent characteristics,including high oxidation ability,low price,and stability,TiO_(2)photocatalyst has been widely studied and used in different scales for numerous decades.For practical applications in these areas,the engineering of the photocatalysts and the design of the PC and PEC devices must be both environmentally and economically sustainable.On the one hand,for the engineering of the photocatalysts,the photocatalyst shall be able to deliver the following characteristics,including large specific surface area,high absorption of light,rapid and low-cost separation and regeneration,and high stability.On the other hand,the design of the PC and PEC devices shall facilitate high in energy utilization and catalytic efficiency,and low in building and operational cost.This work covers the reaction mechanism of TiO_(2)-based PC and PEC technologies,sustainable design,and preparation of TiO_(2)photocatalysts as well as sustainable design in PC and PEC devices for wastewater treatment,sensing,and water splitting.Finally,we provide some critical perspectives on the future development of TiO_(2)-based PC and PEC technology.
基金supported by the National Natural Science Foundation of China(52003253 and 52103308)the China Postdoctoral Science Foundation(2020M672283).
文摘As an indispensable branch of wearable electronics,flexible pressure sensors are gaining tremendous attention due to their extensive applications in health monitoring,human-machine interaction,artificial intelligence,the internet of things,and other fields.In recent years,highly flexible and wearable pressure sensors have been developed using various materials/structures and transduction mechanisms.Morphological engineering of sensing materials at the nanometer and micrometer scales is crucial to obtaining superior sensor performance.This review focuses on the rapid development of morphological engineering technologies for flexible pressure sensors.We discuss different architectures and morphological designs of sensing materials to achieve high performance,including high sensitivity,broad working range,stable sensing,low hysteresis,high transparency,and directional or selective sensing.Additionally,the general fabrication techniques are summarized,including self-assembly,patterning,and auxiliary synthesis methods.Furthermore,we present the emerging applications of high-performing microengineered pressure sensors in healthcare,smart homes,digital sports,security monitoring,and machine learning-enabled computational sensing platform.Finally,the potential challenges and prospects for the future developments of pressure sensors are discussed comprehensively.
基金This research was financially supported by a grant from Ministry of Sciences and Technology(Grant No.2016YFB0302504)grants from National Natural Science Foundation of China(Grant No.31430003)Tsinghua President Fund also supported this project(Grant No.2015THZ10).
文摘Polyhydroxyalkanoates(PHA)have been produced by some bacteria as bioplastics for many years.Yet their commercialization is still on the way.A few issues are related to the difficulty of PHA commercialization:namely,high cost and instabilities on molecular weights(Mw)and structures,thus instability on thermo-mechanical properties.The high cost is the result of complicated bioprocessing associated with sterilization,low conversion of carbon substrates to PHA products,and slow growth of microorganisms as well as difficulty of downstream separation.Future engineering on PHA producing microorganisms should be focused on contamination resistant bacteria especially extremophiles,developments of engineering approaches for the extremophiles,increase on carbon substrates to PHA conversion and controlling Mw of PHA.The concept proof studies could still be conducted on E.coli or Pseudomonas spp.that are easily used for molecular manipulations.In this review,we will use E.coli and halophiles as examples to show how to engineer bacteria for enhanced PHA biosynthesis and for increasing PHA competitiveness.
基金supported by the National Key R&D Program of China(Grant No.2022YFA1505000)the Key R&D Program of Shaanxi Province,China(Grant No.2024CY-GJHX-28)+2 种基金the National Natural Science Foundation of China(Grant No.52302308)the Outstanding Youth Science Foundation Project of the National Natural Science Foundation of China(Overseas)the Qinchuangyuan Cited High-Level Innovative and Entrepreneurial Talents Project,China(Grant No.QCYRCXM-2022-143).
文摘The photocatalytic efficiency of lead-free Bi-based halide perovskites,such as Cs_(3)Bi_(2)X_(9)(X=Br,I)for CO_(2)reduction is often hindered by self-aggregation and insufficient oxidation ability.In this work,a visible-light-driven(λ>420 nm)Z-scheme heterojunction photocatalyst composed of 0D Cs_(3)Bi_(2)I_(9) nanoparticles on 1D WO_(3) nanorods for photocatalytic CO_(2)reduction and water oxidation is synthesized using an in situ growing approach.The resulting 0D/1D Cs_(3)Bi_(2)I_(9)/WO_(3) Z-scheme heterojunction photocatalyst exhibits a visible-light-driven photocatalytic CO_(2)reduction performance for selective CO production,achieving a selectivity of 98.7%and a high rate of 16.5µmol/(g·h),approximately three times that of pristine Cs_(3)Bi_(2)I_(9).Furthermore,it demonstrates decent stability in the gas-solid photocatalytic CO_(2)reduction system.The improved performance of Cs_(3)Bi_(2)I_(9)/WO_(3) is attributed to the formation of the 0D/1D Z-scheme heterojunction,which facilitates charge transfer,reduces charge recombination,and maintains the active sites of both 0D Cs_(3)Bi_(2)I_(9) for CO_(2)reduction and 1D WO_(3) for water oxidation.This work provides valuable insights into the potential of morphological engineering and the design of simultaneous Z-scheme heterojunction for lead-free halide perovskites.
基金financially supported by the National Natural Science Foundation of China (No. 61804097)the Natural Science Foundation of Guangdong Province (No. 2020A1515010792)the Science and Technology Program of Shenzhen (No. SGDX20190918105001787)。
文摘Halide perovskites have attracted great attention due to their high color purity, high luminance yield, low non-radiative recombination rate, and solution processability. Although the external quantum efficiency of perovskite light-emitting diodes(Pe LEDs) is comparable with that of the organic light-emitting diodes(OLEDs) and quantum-dots light-emitting diodes(QLEDs), the brightness is still low compared with the traditional OLEDs and QLEDs. Herein, we demonstrate high brightness and high-efficiency Cs Pb Br3-based Pe LEDs using interface and bulk controlled nanocrystal growth of the perovskite emission layer. The interface engineering by ethanolamine and bulk engineering by polyethylene glycol led to highly crystallized and cubic-shaped perovskite nanocrystals with smooth and compact morphology. As a result, Pe LEDs with a high brightness of 64756 cd/m2 and an external quantum efficiency of 13.4% have been achieved.
文摘Hierarchical tin（Ⅲ） oxide, Sn3O4, nanospheres were synthesized via hydrothermal reaction under strongly acidic ambient conditions. The morphology of Sn3O4 varied with decreasing pH. The prickly SnaO4 nanospheres changed into SnaO4 nanospheres covered with single-crystalline nanoplates having a high BET surface area of ca. 55.05 m^2·g^-1 and a band gap of ca. 2.25 eV. Small amounts （0.05 g） of the hierarchical Sn3O4 nanostructures completely decomposed a 30% methyl orange （MO） solution in 100 mL deionized water within 15 min under one sun condition （UV ＋ visible light）. The Sn3O4 photocatalyst exhibited a fast decomposition rate of 1.73 ×10^-1 min^-1, which is a 90.86% enhancement relative to that of the commercially available P25 photocatalyst. The high photocatalytic activity of the hierarchical Sn3O4 nanostructures is attributed to its ability to absorb visible light and its high surface-to-volume ratio.
基金financial support from the National Natural Science Foundation of China(92163116),the support from the National Natural Science Foundation of China(22209043)the Major Program of the Natural Science Foundation of Hunan Province(2021JC0006)。
基金National Natural Science Foundation of China,Grant/Award Numbers:11828401,11964024,21971113Startup Project of Inner Mongolia University,Grant/Award Number:21200‐5175101+6 种基金National Research Foundation–Competitive Research Program of Singapore,Grant/Award Numbers:CRP22‐2019‐0060,NRF‐CRP21‐2018‐0007,NRF2017‐ANR0022DPSfund of University of Macao,Grant/Award Numbers:MYRG2018‐00079‐IAPME,MYRG2019‐00115‐IAPMEMOE Tier 2,Grant/Award Number:MOE2017‐T2‐2‐136Tier 3,Grant/Award Number:MOE2018‐T3‐1‐002Science and Technology Development Fund of Macao SAR,Grant/Award Numbers:FDCT0059/2018/A2,FDCT009/2017/AMJFund of Shenzhen Science and Technology Innovation Committee,Grant/Award Number:SGDX20201103093600003Shanghai Pujiang Program,Grant/Award Number:20PJ1411500。
文摘Two-dimensional(2D)magnetic crystals with intrinsic ferromagnetism are highly desirable for novel spin-electronic devices.However,the controllable synthesis of 2D magnets,especially the direct growth of 2D magnets on substrate surfaces,is still a challenge.Here,we demonstrate the synthesis of ultrathin zinc-blende phase manganese selenide(β-MnSe)nanosheets using the chemical vapor deposition(CVD)technique.The 2Dβ-MnSe crystals exhibit distinct ferromagnetic properties with a Curie temperature of 42.3 K.Density functional theory(DFT)calculations suggest that the ferromagnetic order inβ-MnSe originates from the exchange coupling between the unsaturated Se and Mn atoms.This study presents significant progress in the CVD growth of ultrathin 2D magnetic materials by thinning bulk magnets,and it will pave the way for the building of energy-efficient spintronic devices in the future.
