Metal sulfides are a class of promising anode materials for sodium-ion batteries(SIBs)owing to their high theoretical specific capacity.Nevertheless,the reactant products(polysulfides)could dissolve into electrolyte,s...Metal sulfides are a class of promising anode materials for sodium-ion batteries(SIBs)owing to their high theoretical specific capacity.Nevertheless,the reactant products(polysulfides)could dissolve into electrolyte,shuttle across separator,and react with sodium anode,leading to severe capacity loss and safety concerns.Herein,for the first time,gallium(Ga)-based liquid metal(LM)alloy is incorporated with MoS_(2)nanosheets to work as an anode in SIBs.The electron-rich,ultrahigh electrical conductivity,and self-healing properties of LM endow the heterostructured MoS_(2)-LM with highly improved conductivity and electrode integrity.Moreover,LM is demonstrated to have excellent capability for the adsorption of polysulfides(e.g.,Na_(2)S,Na_(2)S_(6),and S_(8))and subsequent catalytic conversion of Na_(2)S.Consequently,the MoS_(2)-LM electrode exhibits superior ion diffusion kinetics and long cycling performance in SIBs and even in lithium/potassium-ion battery(LIB/PIB)systems,far better than those electrodes with conventional binders(polyvinylidene difluoride(PVDF)and sodium carboxymethyl cellulose(CMC)).This work provides a unique material design concept based on Ga-based liquid metal alloy for metal sulfide anodes in rechargeable battery systems and beyond.展开更多
对一种简单结构的喹哪啶衍生物作为离子荧光探针的性能进行了研究。探针由8-羟基喹哪啶的2-位引入水杨醛构成,通过双键连接喹啉环与苯环以及推-拉电子基团构成大共轭结构,使其发光量子产率提高;探针分子中的氮、氧原子提供了良好的配位...对一种简单结构的喹哪啶衍生物作为离子荧光探针的性能进行了研究。探针由8-羟基喹哪啶的2-位引入水杨醛构成,通过双键连接喹啉环与苯环以及推-拉电子基团构成大共轭结构,使其发光量子产率提高;探针分子中的氮、氧原子提供了良好的配位作用点,能选择性与离子配合而使荧光性质发生变化。在乙腈/水溶液中,Fe^(3+)与探针形成1∶1的配合物而使其荧光猝灭,配合为自发的熵驱动放热过程。红外光谱和1 H NMR滴定推测探针分子中的两个羰基氧和氮的孤对电子参与Fe^(3+)络合,光诱导引发电子转移过程导致荧光猝灭。在乙腈溶液中,F^-使探针在415nm处的荧光峰降低,在560nm处出现新荧光峰,形成比率荧光,荧光由蓝色变为黄色至橙红色。同时,F^-使探针在280和340nm处的紫外吸收峰降低,在455nm处出现新的吸收峰,形成比率吸收,颜色由无色变为黄色至橙色。1 H NMR滴定推测探针分子与F^-是通过氢键作用。为一种同时检测阴、阳离子的双功能探针,荧光法对Fe^(3+)和F^-的检出限分别低至13.6nmol·L^(-1)和1.6μmol·L^(-1),紫外法对F^-的检出限低至16.5μmol·L^(-1)。利用探针对F^-识别时明显的颜色变化,建立了可视性,快速度,易操作的目视检测微量F^-的方法。展开更多
Perovskite solar cells(PSCs)have attracted tremendous attention as a promising alternative candidate for clean energy generation.Many attempts have been made with various deposition techniques to scale-up manufacturin...Perovskite solar cells(PSCs)have attracted tremendous attention as a promising alternative candidate for clean energy generation.Many attempts have been made with various deposition techniques to scale-up manufacturing.Slot-die coating is a robust and facile deposition technique that can be applied in large-area roll-to-roll(R2R)fabrication of thin film solar cells with the advantages of high material utilization,low cost and high throughput.Herein,we demonstrate the encouraging result of PSCs prepared by slot-die coating under ambient environment using a twostep sequential process whereby PbI_(2):CsI is slot-die coated first followed by a subsequent slot-die coating of organic cations containing solution.A porous PbI_(2):CsI film can promote the rapid and complete transformation into perovskite film.The crystallinity and morphology of perovskite films are significantly improved by optimizing nitrogen blowing and controlling substrate temperature.A power conversion efficiency(PCE)of 18.13%is achieved,which is promising for PSCs fabricated by two-step fully slot-die-coated devices.Furthermore,PSCs with a 1 cm2 area yield a champion PCE of 15.10%.Moreover,a PCE of 13.00%is obtained on a flexible substrate by the roll-to-roll(R2R)coating,which is one of the highest reported cells with all layers except for metal electrode fabricated by R2R process under ambient condition.展开更多
This paper suggests development of a flexible,lightweight,and ultra-sensitive piezoresistive flow sensor based on vertical graphene nanosheets(VGNs) with a mazelike structure.The sensor was thoroughly characterized fo...This paper suggests development of a flexible,lightweight,and ultra-sensitive piezoresistive flow sensor based on vertical graphene nanosheets(VGNs) with a mazelike structure.The sensor was thoroughly characterized for steady-state and oscillatory water flow monitoring applications.The results demonstrated a high sensitivity(103.91 mV(mm/s)-1) and a very low-velocity detection threshold(1.127 mm s-1) in steady-state flow monitoring.As one of many potential applications,we demonstrated that the proposed VGNs/PDMS flow sensor can closely mimic the vestibular hair cell sensors housed inside the semicircular canals(SCCs).As a proof of concept,magnetic resonance imaging of the human inner ear was conducted to measure the dimensions of the SCCs and to develop a 3D printed lateral semicircular canal(LSCC).The sensor was embedded into the artificial LSCC and tested for various physiological movements.The obtained results indicate that the flow sensor is able to distinguish minute changes in the rotational axis physical geometry,frequency,and amplitude.The success of this study paves the way for extending this technology not only to vestibular organ prosthesis but also to other applications such as blood/urine flow monitoring,intravenous therapy(Ⅳ),water leakage monitoring,and unmanned underwater robots through incorporation of the appropriate packaging of devices.展开更多
Nanostructured graphene films were used as platforms for the differentiation of Saos-2 cells into bonelike cells. The films were grown using the plasma-enhanced chemical vapor deposition method, which allowed the prod...Nanostructured graphene films were used as platforms for the differentiation of Saos-2 cells into bonelike cells. The films were grown using the plasma-enhanced chemical vapor deposition method, which allowed the production of both vertically and horizontally aligned carbon nanowalls(CNWs). Modifications of the techniqueallowed control of the density of the CNWs and their orientation after the transfer process. The influence of two different topographies on cell attachment, proliferation,and differentiation was investigated. First, the transferred graphene surfaces were shown to be noncytotoxic and were able to support cell adhesion and growth for over 7 days.Second, early cell differentiation(identified by cellular alkaline phosphatase release) was found to be enhanced on the horizontally aligned CNW surfaces, whereas mineralization(identified by cellular calcium production), a later stage of bone cell differentiation, was stimulated by the presence of the vertical CNWs on the surfaces. These results show that the graphene coatings, grown using the presented method, are biocompatible. And their topographies have an impact on cell behavior, which can be useful in tissue engineering applications.展开更多
Fluxing agents of zinc borate, antimony oxide, galss frit A and glass frit B, with different melting or softening point temperatures, were added into MgO-Al_2O_3-SiO_2/boron phenol formaldehyde resin（MAS/BPF） compos...Fluxing agents of zinc borate, antimony oxide, galss frit A and glass frit B, with different melting or softening point temperatures, were added into MgO-Al_2O_3-SiO_2/boron phenol formaldehyde resin（MAS/BPF） composites to lower the formation temperature of eutectic liquid phase and promote the ceramification of ceramifiable composites. The effects of fluxing agents on the thermogravimetric properties, phase evolution, and microstructure evolution of MAS/BPF composites were characterized by TG-DSC, XRD and SEM analyses. The results reveal that the addition of a fluxing agent highly reduces the decomposition rate of MAS/BPF composites. Fluxing agents lower the formation temperatures of liquid phases of ceramifiable MAS/BPF composites obviously, and then promote the ceramification and densification process. The final residues of composites are ceramic surrounded by large amount of glass phases.展开更多
In-situ transmission X-ray diffraction based compression deformation experiments are performed to study the twinning behaviour in asextruded(non-aged)and peak-aged Mg-7Sn-3Zn-0.04Na alloy.The axial lattice strains wer...In-situ transmission X-ray diffraction based compression deformation experiments are performed to study the twinning behaviour in asextruded(non-aged)and peak-aged Mg-7Sn-3Zn-0.04Na alloy.The axial lattice strains were measured in the parent grains,twins and the precipitates as a function of applied stress.The critical shear stress for achieving 5%twinning was found to be increased by∼26MPa by the presence of 7%of Sn and by∼50MPa by the presence of the particles formed after 10 h of aging.The evolution of twin volume fraction with plastic strain is similar in both non-aged and aged conditions,indicating no change in the relative activities of slip and twin in the ideally oriented(10.10)parent grains.Predictions made in previous studies of twin thickening stresses and twin bypass stresses agree reasonably well with the measured values,given the experimental error.Considerable relaxation was seen in the precipitate lattice reflections.This is attributed to relaxation effects continuing during X-ray data collection.Macroscopic flow curves confirm that precipitate hardening in the present system is particularly sensitive to relaxation effects.This is likely to be an important consideration for fatigue loading of precipitate hardened samples.展开更多
Using solar energy to produce syngas via the endothermic reforming of methane has been extensively inves- tigated at the laboratory- and pilot plant-scales as a promising method of storing solar energy. One of the cha...Using solar energy to produce syngas via the endothermic reforming of methane has been extensively inves- tigated at the laboratory- and pilot plant-scales as a promising method of storing solar energy. One of the challenges to scaling up this process in a tubular reformer is to improve the reactor＇s performance, which is limited by mass and heat transfer issues. High thermal conductivity Cu foam was therefore used as a sub-strate to improve the catalyst＇s thermal conductivity during solar reforming. We also developed a method to coat the foam with the catalytically active component NiMg3AlOx. The Cu foam-based NiMg3AlOx performs better than catalysts supported on SiSiC foam, which is currently used as a substrate for solar-reforming cat- alysts, at high gas hourly space velocity （≥400,000 mL/（g.h）） or at low reaction temperatures （≤ 720 ℃）. The presence of a γ-Al2O3 intermediate layer improves the adhesion between the catalyst and substrate as well as the catalytic activity.展开更多
As the widely implemented electrode material,graphite has the characteristic of sublimation by the thermal shock of the switching arc,and the produced carbon vapor is easy to condense into carbon powders and deposit i...As the widely implemented electrode material,graphite has the characteristic of sublimation by the thermal shock of the switching arc,and the produced carbon vapor is easy to condense into carbon powders and deposit in the switch.The impact of the type of dilution gas in a mixture of20%oxygen and 80%dilution gas on the sublimation and oxidation characteristics of the graphite electrode is investigated.It is found that when nitrogen dilution gas was replaced by argon,the heat flux to the electrodes decreased,which led to a 63%reduction of graphite sublimation.At the same time,the cooling rate of the arc was slower in argon,which promotes oxidation of the carbon vapor.The residual solid carbon can be reduced by 70%–85%by using argon as the dilution gas.Consequently,it is demonstrated that the stability and working life of the switch could be increased by appropriate selection of the dilution gas.展开更多
Functionalized graphene nano-platelets(FGN) were obtained via treating graphene nanoplatelets(GN) with HNO3, and served as adsorbent for the removal of Pb2+from solutions. We investigated the FGN adsorption capacity f...Functionalized graphene nano-platelets(FGN) were obtained via treating graphene nanoplatelets(GN) with HNO3, and served as adsorbent for the removal of Pb2+from solutions. We investigated the FGN adsorption capacity for Pb2+at different initial concentrations, varying pH, contact time and temperature. The characterization results of scanning electron microscopy(SEM), thermal analysis(TG/DTG), Fourier transform infrared spectroscopy(FT-IR) and Brunauer-Emmett-Teller(BET) method indicated that FGN layers were thin and possess large specific area with oxygen-containing functional groups grafted onto their surface. Meanwhile, the determined equilibrium adsorption capacity of FGN for Pb2+was 57.765 mg/g and adsorption isotherms well confirmed to Langmuir isotherms models. The results reveals that the FGN has better effect of water treatment.展开更多
基金the financial support from the Australian Research Council (ARC) through Future Fellowship (FT210100298)DECRA Fellowship (DE230101068)+2 种基金Discovery Project (DP230100198 and DP210102215)Linkage Projects (LP220100088 and LP180100722)partially supported by AIIM FOR GOLD Grant (2017, 2018)
文摘Metal sulfides are a class of promising anode materials for sodium-ion batteries(SIBs)owing to their high theoretical specific capacity.Nevertheless,the reactant products(polysulfides)could dissolve into electrolyte,shuttle across separator,and react with sodium anode,leading to severe capacity loss and safety concerns.Herein,for the first time,gallium(Ga)-based liquid metal(LM)alloy is incorporated with MoS_(2)nanosheets to work as an anode in SIBs.The electron-rich,ultrahigh electrical conductivity,and self-healing properties of LM endow the heterostructured MoS_(2)-LM with highly improved conductivity and electrode integrity.Moreover,LM is demonstrated to have excellent capability for the adsorption of polysulfides(e.g.,Na_(2)S,Na_(2)S_(6),and S_(8))and subsequent catalytic conversion of Na_(2)S.Consequently,the MoS_(2)-LM electrode exhibits superior ion diffusion kinetics and long cycling performance in SIBs and even in lithium/potassium-ion battery(LIB/PIB)systems,far better than those electrodes with conventional binders(polyvinylidene difluoride(PVDF)and sodium carboxymethyl cellulose(CMC)).This work provides a unique material design concept based on Ga-based liquid metal alloy for metal sulfide anodes in rechargeable battery systems and beyond.
文摘对一种简单结构的喹哪啶衍生物作为离子荧光探针的性能进行了研究。探针由8-羟基喹哪啶的2-位引入水杨醛构成,通过双键连接喹啉环与苯环以及推-拉电子基团构成大共轭结构,使其发光量子产率提高;探针分子中的氮、氧原子提供了良好的配位作用点,能选择性与离子配合而使荧光性质发生变化。在乙腈/水溶液中,Fe^(3+)与探针形成1∶1的配合物而使其荧光猝灭,配合为自发的熵驱动放热过程。红外光谱和1 H NMR滴定推测探针分子中的两个羰基氧和氮的孤对电子参与Fe^(3+)络合,光诱导引发电子转移过程导致荧光猝灭。在乙腈溶液中,F^-使探针在415nm处的荧光峰降低,在560nm处出现新荧光峰,形成比率荧光,荧光由蓝色变为黄色至橙红色。同时,F^-使探针在280和340nm处的紫外吸收峰降低,在455nm处出现新的吸收峰,形成比率吸收,颜色由无色变为黄色至橙色。1 H NMR滴定推测探针分子与F^-是通过氢键作用。为一种同时检测阴、阳离子的双功能探针,荧光法对Fe^(3+)和F^-的检出限分别低至13.6nmol·L^(-1)和1.6μmol·L^(-1),紫外法对F^-的检出限低至16.5μmol·L^(-1)。利用探针对F^-识别时明显的颜色变化,建立了可视性,快速度,易操作的目视检测微量F^-的方法。
基金the National Natural Science Foundation of China(Grant No.52173192)the National Key Research and Development Program of China(Grant No.2017YFA0206600)+1 种基金HL also acknowledges the support from the Key Innovation Project of Graduate of Central South University(Grant No.2018ZZTS106)and China Scholarship Council programOpen access funding provided by Shanghai Jiao Tong University
文摘Perovskite solar cells(PSCs)have attracted tremendous attention as a promising alternative candidate for clean energy generation.Many attempts have been made with various deposition techniques to scale-up manufacturing.Slot-die coating is a robust and facile deposition technique that can be applied in large-area roll-to-roll(R2R)fabrication of thin film solar cells with the advantages of high material utilization,low cost and high throughput.Herein,we demonstrate the encouraging result of PSCs prepared by slot-die coating under ambient environment using a twostep sequential process whereby PbI_(2):CsI is slot-die coated first followed by a subsequent slot-die coating of organic cations containing solution.A porous PbI_(2):CsI film can promote the rapid and complete transformation into perovskite film.The crystallinity and morphology of perovskite films are significantly improved by optimizing nitrogen blowing and controlling substrate temperature.A power conversion efficiency(PCE)of 18.13%is achieved,which is promising for PSCs fabricated by two-step fully slot-die-coated devices.Furthermore,PSCs with a 1 cm2 area yield a champion PCE of 15.10%.Moreover,a PCE of 13.00%is obtained on a flexible substrate by the roll-to-roll(R2R)coating,which is one of the highest reported cells with all layers except for metal electrode fabricated by R2R process under ambient condition.
基金financial support from Australian Research Council(ARC)via Discovery Early Career Researcher Awards(DE180100688 and DE170100284).
文摘This paper suggests development of a flexible,lightweight,and ultra-sensitive piezoresistive flow sensor based on vertical graphene nanosheets(VGNs) with a mazelike structure.The sensor was thoroughly characterized for steady-state and oscillatory water flow monitoring applications.The results demonstrated a high sensitivity(103.91 mV(mm/s)-1) and a very low-velocity detection threshold(1.127 mm s-1) in steady-state flow monitoring.As one of many potential applications,we demonstrated that the proposed VGNs/PDMS flow sensor can closely mimic the vestibular hair cell sensors housed inside the semicircular canals(SCCs).As a proof of concept,magnetic resonance imaging of the human inner ear was conducted to measure the dimensions of the SCCs and to develop a 3D printed lateral semicircular canal(LSCC).The sensor was embedded into the artificial LSCC and tested for various physiological movements.The obtained results indicate that the flow sensor is able to distinguish minute changes in the rotational axis physical geometry,frequency,and amplitude.The success of this study paves the way for extending this technology not only to vestibular organ prosthesis but also to other applications such as blood/urine flow monitoring,intravenous therapy(Ⅳ),water leakage monitoring,and unmanned underwater robots through incorporation of the appropriate packaging of devices.
基金partially supported by the Australian Research Council (DP160103116)CSIRO’s OCE Science Leadership Schemethe scholarship support from the National Council for Science and Technology Development (CNPq-Brasil)
文摘Nanostructured graphene films were used as platforms for the differentiation of Saos-2 cells into bonelike cells. The films were grown using the plasma-enhanced chemical vapor deposition method, which allowed the production of both vertically and horizontally aligned carbon nanowalls(CNWs). Modifications of the techniqueallowed control of the density of the CNWs and their orientation after the transfer process. The influence of two different topographies on cell attachment, proliferation,and differentiation was investigated. First, the transferred graphene surfaces were shown to be noncytotoxic and were able to support cell adhesion and growth for over 7 days.Second, early cell differentiation(identified by cellular alkaline phosphatase release) was found to be enhanced on the horizontally aligned CNW surfaces, whereas mineralization(identified by cellular calcium production), a later stage of bone cell differentiation, was stimulated by the presence of the vertical CNWs on the surfaces. These results show that the graphene coatings, grown using the presented method, are biocompatible. And their topographies have an impact on cell behavior, which can be useful in tissue engineering applications.
文摘Fluxing agents of zinc borate, antimony oxide, galss frit A and glass frit B, with different melting or softening point temperatures, were added into MgO-Al_2O_3-SiO_2/boron phenol formaldehyde resin（MAS/BPF） composites to lower the formation temperature of eutectic liquid phase and promote the ceramification of ceramifiable composites. The effects of fluxing agents on the thermogravimetric properties, phase evolution, and microstructure evolution of MAS/BPF composites were characterized by TG-DSC, XRD and SEM analyses. The results reveal that the addition of a fluxing agent highly reduces the decomposition rate of MAS/BPF composites. Fluxing agents lower the formation temperatures of liquid phases of ceramifiable MAS/BPF composites obviously, and then promote the ceramification and densification process. The final residues of composites are ceramic surrounded by large amount of glass phases.
基金This research was supported by the Australian Research Council’s Discovery research grant(DP150101577).
文摘In-situ transmission X-ray diffraction based compression deformation experiments are performed to study the twinning behaviour in asextruded(non-aged)and peak-aged Mg-7Sn-3Zn-0.04Na alloy.The axial lattice strains were measured in the parent grains,twins and the precipitates as a function of applied stress.The critical shear stress for achieving 5%twinning was found to be increased by∼26MPa by the presence of 7%of Sn and by∼50MPa by the presence of the particles formed after 10 h of aging.The evolution of twin volume fraction with plastic strain is similar in both non-aged and aged conditions,indicating no change in the relative activities of slip and twin in the ideally oriented(10.10)parent grains.Predictions made in previous studies of twin thickening stresses and twin bypass stresses agree reasonably well with the measured values,given the experimental error.Considerable relaxation was seen in the precipitate lattice reflections.This is attributed to relaxation effects continuing during X-ray data collection.Macroscopic flow curves confirm that precipitate hardening in the present system is particularly sensitive to relaxation effects.This is likely to be an important consideration for fatigue loading of precipitate hardened samples.
基金supported by the CSIRO Energy Flagship and the Chinese Scholarship Council
文摘Using solar energy to produce syngas via the endothermic reforming of methane has been extensively inves- tigated at the laboratory- and pilot plant-scales as a promising method of storing solar energy. One of the challenges to scaling up this process in a tubular reformer is to improve the reactor＇s performance, which is limited by mass and heat transfer issues. High thermal conductivity Cu foam was therefore used as a sub-strate to improve the catalyst＇s thermal conductivity during solar reforming. We also developed a method to coat the foam with the catalytically active component NiMg3AlOx. The Cu foam-based NiMg3AlOx performs better than catalysts supported on SiSiC foam, which is currently used as a substrate for solar-reforming cat- alysts, at high gas hourly space velocity （≥400,000 mL/（g.h）） or at low reaction temperatures （≤ 720 ℃）. The presence of a γ-Al2O3 intermediate layer improves the adhesion between the catalyst and substrate as well as the catalytic activity.
基金supported by National Natural Science Foundation of China(Nos.51777082 and 52077091)Chinese Scholarship Council(No.201906160101)。
文摘As the widely implemented electrode material,graphite has the characteristic of sublimation by the thermal shock of the switching arc,and the produced carbon vapor is easy to condense into carbon powders and deposit in the switch.The impact of the type of dilution gas in a mixture of20%oxygen and 80%dilution gas on the sublimation and oxidation characteristics of the graphite electrode is investigated.It is found that when nitrogen dilution gas was replaced by argon,the heat flux to the electrodes decreased,which led to a 63%reduction of graphite sublimation.At the same time,the cooling rate of the arc was slower in argon,which promotes oxidation of the carbon vapor.The residual solid carbon can be reduced by 70%–85%by using argon as the dilution gas.Consequently,it is demonstrated that the stability and working life of the switch could be increased by appropriate selection of the dilution gas.
基金Funded by the National Natural Science Fundation of China(Nos.51678111 and 51478082)
文摘Functionalized graphene nano-platelets(FGN) were obtained via treating graphene nanoplatelets(GN) with HNO3, and served as adsorbent for the removal of Pb2+from solutions. We investigated the FGN adsorption capacity for Pb2+at different initial concentrations, varying pH, contact time and temperature. The characterization results of scanning electron microscopy(SEM), thermal analysis(TG/DTG), Fourier transform infrared spectroscopy(FT-IR) and Brunauer-Emmett-Teller(BET) method indicated that FGN layers were thin and possess large specific area with oxygen-containing functional groups grafted onto their surface. Meanwhile, the determined equilibrium adsorption capacity of FGN for Pb2+was 57.765 mg/g and adsorption isotherms well confirmed to Langmuir isotherms models. The results reveals that the FGN has better effect of water treatment.
