Achieving high energy density and fast charging of lithium-ion batteries can accelerate the promotion of electric vehicles.However,the increased mass loading causes poor charge transfer,impedes the electrochemical rea...Achieving high energy density and fast charging of lithium-ion batteries can accelerate the promotion of electric vehicles.However,the increased mass loading causes poor charge transfer,impedes the electrochemical reaction kinetics,and limits the battery charging rate.Herein,this work demonstrated a novel pattern integrated stamping process for creating channels in the electrode,which benefits ion transport and increases the rate performance of the electrode.Meanwhile,the pressure applied during the stamping process improved the contact between electrode and current collector and also enhanced the mechanical stability of the electrode.Compared to the conventional bar-coated electrode with the same thickness of 155μm(delivered a discharge capacity of 16 mAh g^(−1) at the rate of 3 C),the stamped low-tortuosity LiFePO_(4) electrode delivered 101 mAh g^(−1) capacity.Additionally,water was employed as a solvent in this study.Owing to its eco-friendliness,high scalability,and minimal waste generation,this novel stamping technique inspire a new method for the industrial-level efficient roll to roll fabrication of fast-charge electrodes.展开更多
Polycystic ovary syndrome(PCOS)is an endocrine disorder caused by hypothalamic-pituitary-ovarian(HPO)axis dysfunction.In the field of gynecology and reproduction,PCOS has emerged as both a research hot spot and a chal...Polycystic ovary syndrome(PCOS)is an endocrine disorder caused by hypothalamic-pituitary-ovarian(HPO)axis dysfunction.In the field of gynecology and reproduction,PCOS has emerged as both a research hot spot and a challenging area of study.According to Chinese medicine,this disease is related to kidney deficiency,phlegm and dampness obstruction,blood stasis and interconnection,Chong pulse impassability,the lack of Ren pulse,and the loss of uterine nourishment,all of which affect the normal development and maturation of eggs as well as the duration at which menstrual blood stores.In this paper,based on the theoretical basis of“liver collects blood,regulates the flow of qi,and is the master of drainage,”we explore the rationality of the treatment of this disease from the perspective of“liver and kidney have the same origin”and the development of PCOS-related infertility in relation to dysfunctional internal organs.We also explore the feasibility of treatment from the perspective of“liver and kidney homology,”expand the ideas for treatment,as well as develop and innovate the application of organ identification in PCOS in relation to infertility.展开更多
Secondary batteries have been widely developed and used in various fields,such as large-scale energy storage,portable electronics,and electric vehicles.Carbon-based materials have attracted considerable attention due ...Secondary batteries have been widely developed and used in various fields,such as large-scale energy storage,portable electronics,and electric vehicles.Carbon-based materials have attracted considerable attention due to their abundance,environmental friendliness,tunable structure,and excellent chemical stability.Beyond the commercial carbon for batteries and supercapacitors,many studies focused on advanced and multifunctional carbon with various structures for electrochemical energy storage.This review summarizes the zero-to three-dimensional carbon-based materials and reviews their various electrochemical applications based on their structural characteristics.The importance of carbon structures and the relationship between materials'structures and electrochemical performance are discussed.Then,the prospects and potential challenges of using advanced carbon to formulate designs and develop novel carbonaceous materials with high electrochemical performance are further discussed.展开更多
[Objectives] This study was conducted to investigate the possibility of screening for herbicide resistance in the early stage of rapes growth. [Methods] Eight treatments were set for a herbicide concentration experime...[Objectives] This study was conducted to investigate the possibility of screening for herbicide resistance in the early stage of rapes growth. [Methods] Eight treatments were set for a herbicide concentration experiment. [Results] Rape sprouts were highly sensitive to the herbicide glyphosate, and even a very low concentration of glyphosate solution(187 mg/L) was sufficient to kill most of the rape seedlings, while the genetically modified herbicide-tolerant rape could tolerate higher concentrations of the herbicide. Low concentrations of glyphosate could be used for screening at the sprout stage, and the results of herbicide-tolerance screening were consistent with PCR testing. [Conclusions] This study lays a technical and material foundation for accelerating the cultivation of new herbicide-resistant rape varieties suitable for rapeseed production areas in the lower reaches of the Yangtze River.展开更多
Objective:To systematically evaluate the efficacy and safety of didroxyprogesterone combined with progesterone in the treatment of luteal insufficiency abortion.Methods:We searched CNKI database,VIP database,Wanfang d...Objective:To systematically evaluate the efficacy and safety of didroxyprogesterone combined with progesterone in the treatment of luteal insufficiency abortion.Methods:We searched CNKI database,VIP database,Wanfang database,PubMed database,EMBASE database and Cochrane library database for literatures on the treatment of luteal insufficiency-induced abortion with didroxyprogesterone and progesterone.Meta-analysis was performed using Revman 5.3 software after literature extraction and further quality evaluation.Results:Ten randomized controlled trial-related articles that describe studies on a total of 1145 patients,570 in the combination group and 575 in the control group,were included.The results of meta-analysis showed that combination therapy could improve the effective rate of fetal protection(OR=0.14,95%CI[0.07,0.27],P<0.00001).The safety of the combination group was significantly higher than that of the control group(OR=3.09,95%CI[1.13,8.48],P=0.03).Conclusion:To sum up,compared with the control group,the combination of progesterone and progesterone is more effective and safer in the treatment of luteal insufficiency abortion.However,the sample size of the data is relatively small and the quality of the literature is low.This conclusion still needs to be further verified in high-quality randomized controlled trials that involve large samples.展开更多
Polycystic ovary syndrome(PCOS)is a disease with reproductive dysfunction and abnormal endocrine metabolism.It is characterized by hyperandrogenism,insulin resistance(IR)and persistent anovulation.At present,the patho...Polycystic ovary syndrome(PCOS)is a disease with reproductive dysfunction and abnormal endocrine metabolism.It is characterized by hyperandrogenism,insulin resistance(IR)and persistent anovulation.At present,the pathogenesis and pathological mechanism of PCOS are still unclear,and there is no unified standard for the diagnosis and treatment of PCOS locally nor abroad.It is still a famous and difficult problem to explore the pathogenesis of PCOS and seek effective prevention and treatment methods.展开更多
Autophagy is a self-protection mechanism of the body,and also an important physiological process for cells to maintain internal environment stability.Studies have shown that the degree of autophagy damage is positivel...Autophagy is a self-protection mechanism of the body,and also an important physiological process for cells to maintain internal environment stability.Studies have shown that the degree of autophagy damage is positively correlated with the expression of oncogenes,and the expression of oncogenes is closely related to cervical HPV infection,so the control of autophagy ability can interfere with cervical HPV virus infection.Traditional Chinese medicine believes that dampness-heat evil down,can damage and Chong Ren cell.The author believes that autophagy damage and the theory of dampness-heat injection in cervical HPV infection have similar pathogenic mechanism,and explores the prevention and treatment of autophagy and cervical HPV infection based on the theory of traditional Chinese medicine dampness-heat injection,in attempt to provide a new treatment for clinical prevention and treatment.展开更多
Traditional medicine believes that emotional,room labor and other factors lead to the lack of blood circulation after the weather,and the consumption of Yin blood is too much,which can lead to the deficiency of blood ...Traditional medicine believes that emotional,room labor and other factors lead to the lack of blood circulation after the weather,and the consumption of Yin blood is too much,which can lead to the deficiency of blood essence.Over time,the deficiency of menstrual blood can not nourish the kidney essence,leading to abnormal pregnancy.The liver is congenital for women,and the kidney is congenital.The disharmony of liver and kidney is the key factor of women's disease.Starting from the"homology of Yi and GUI",this paper analyzes the main etiology and pathogenesis of the disease from three aspects:deficiency of blood essence,imbalance of Zang and Xie,and Yin not controlling Yang.Following the principle of simultaneous treatment of liver and kidney,starting from the three methods of "regulating and tonifying liver and kidney,tonifying kidney and activating blood circulation,and balancing yin and Yang",the liver and kidney are reconciled,and pregnancy is sometimes the best choice.The main purpose is to benefit PCOS patients.展开更多
The main cause of infertility in elderly women is poor ovarian function,decreased quality and number of oocytes,which ultimately leads to poor fertility.Low ovarian function is the most difficult point in the research...The main cause of infertility in elderly women is poor ovarian function,decreased quality and number of oocytes,which ultimately leads to poor fertility.Low ovarian function is the most difficult point in the research of reproductive medicine and reproductive health.At present,the treatment of integrated traditional Chinese and Western medicine has gradually achieved results.Western medicine mainly regulates endocrine and assisted reproductive treatment by supplementing estrogen and progesterone,while traditional Chinese medicine(TCM)mainly focuses on invigorating the kidney,adding and subtracting according to the syndrome.The treatment effect of TCM or western medicine alone is not significant.Many clinical observations show that integrated TCM and western medicine focuses on the specialties of western medicine,which not only makes up for the insufficiency of the slow action of TCM,but also improves its clinical efficacy when combined with western medicine.Based on domestic and foreign research,this article summarizes the treatment of infertility in elderly women with integrated TCM and western medicine.展开更多
Porous carbon materials are widely used in particulate forms for energy applications such as fuel cells, batteries, and （super） capacitors. To better hold the particles together, polymeric additives are utilized as ...Porous carbon materials are widely used in particulate forms for energy applications such as fuel cells, batteries, and （super） capacitors. To better hold the particles together, polymeric additives are utilized as binders, which not only increase the weight and volume of the devices, but also cause adverse side effects. We developed a wood-derived, free-standing porous carbon electrode and successfully applied it as a cathode in Li-O2 batteries. The spontaneously formed hierarchical porous structure exhibits good performance in facilitating the mass transport and hosting the discharge products of Li202. Heteroatom （N） doping further improves the catalytic activity of the carbon cathode with lower overpotential and higher capacity. Overall, the Li-O2 battery based on the new carbon cathode affords a stable energy efficiency of 65% and can be operated for 20 cycles at a discharge depth of 70%. The wood-derived free-standing carbon represents a new, unique structure for energy applications.展开更多
Recent advances in next-generation energy storage devices have focused on flexible and wearable all-solid-state lithium batteries(ASSLBs),mainly because of their advantages in terms of safety and extensive application...Recent advances in next-generation energy storage devices have focused on flexible and wearable all-solid-state lithium batteries(ASSLBs),mainly because of their advantages in terms of safety and extensive applications.Among various tech-nologies for the preparation of flexible electrodes,electrospinning is a straightforward operation and cost-effective mean for the facile fabrication of flexible nanofibers and the versatile design of nanofiber structure.Herein,current technologies for engineering electrospun nanofiber structures and their state-of-the-art implementation in flexible ASSLBs are reviewed.First,current strategies for nanofiber structural design,including advances in high-specific surface area,superior mechanical flexibility,and various nanostructures,are systematically discussed.Subsequently,the utilization of electrospun nanofibers in ASSLBs is reviewed.Electrospinning of flexible and highly ion-conductive solid-state electrolytes(SSEs)is emphasized,and current nanofiber structural designs for SSEs and electrodes for ASSLBs are introduced.Despite these advances,there have not been enough studies of the integration of versatile electrospinning techniques in nanofiber structural design for both SSEs and electrodes.In the final section,promising pathways to implement versatile electrospinning in flexible ASSLBs with superior electrochemical performance and stable cycling properties are discussed.Thus,this review provides a holistic overview of the state of the art of electrospinning for high-performance flexible ASSLBs,which could safely power next-generation flexible devices.展开更多
Considering the growing concerns about natural resource depletion,energy inequality,and climate crises,biomassderived materials—the most abundant organic matter on the planet—have received a lot of attention as a po...Considering the growing concerns about natural resource depletion,energy inequality,and climate crises,biomassderived materials—the most abundant organic matter on the planet—have received a lot of attention as a potential alternative to petroleum-based plastics.Herbaceous biomasses and extracted cellulose have recently been extensively used in the development of high-performance and multifunctional materials.Herbaceous biomass has sparked interest due to its species diversity,abundance,low cost,lightweight,and sustainability.This review discusses the structure versus property relationships of various sources of herbaceous biomasses(e.g.,sugarcane,straw,and bamboo)and their extracted biomaterials,as well as the latest emerging applications from macro-and microscales to nanoscales.High-strength structural materials,porous carbon materials,multichannel materials,and flexible materials are examples of these applications,which include sustainable electronics,environmentally friendly energy harvesting,smart materials,and biodegradable structural buildings.展开更多
Element sulfur in nature is an insulating solid.While it has been tested that one-dimensional sulfur chain is metallic and conducting,the investigation on two-dimensional sulfur remains elusive.We report that molybden...Element sulfur in nature is an insulating solid.While it has been tested that one-dimensional sulfur chain is metallic and conducting,the investigation on two-dimensional sulfur remains elusive.We report that molybdenum disulfide layers are able to serve as the nanotemplate to facilitate the formation of two-dimensional sulfur.Density functional theory calculations suggest that confined inbetween layers of molybdenum disulfide,sulfur atoms are able to form two-dimensional triangular arrays that are highly metallic.As a result,these arrays contribute to the high conductivity and metallic phase of the hybrid structures of molybdenum disulfide layers and two-dimensional sulfur arrays.The experimentally measured conductivity of such hybrid structures reaches up to 223 S/m.Multiple experimental results,including X-ray photoelectron spectroscopy(XPS),transition electron microscope(TEM),selected area electron diffraction(SAED),agree with the computational insights.Due to the excellent conductivity,the current density is linearly proportional to the scan rate until 30,000 mV s^(−1) without the attendance of conductive additives.Using such hybrid structures as electrode,the two-electrode supercapacitor cells yield a power density of 10^(6) Wh kg^(−1) and energy density ~47.5 Wh kg^(−1) in ionic liquid electrolytes.Our findings offer new insights into using two-dimensional materials and their Van der Waals heterostructures as nanotemplates to pattern foreign atoms for unprecedented material properties.展开更多
文摘Achieving high energy density and fast charging of lithium-ion batteries can accelerate the promotion of electric vehicles.However,the increased mass loading causes poor charge transfer,impedes the electrochemical reaction kinetics,and limits the battery charging rate.Herein,this work demonstrated a novel pattern integrated stamping process for creating channels in the electrode,which benefits ion transport and increases the rate performance of the electrode.Meanwhile,the pressure applied during the stamping process improved the contact between electrode and current collector and also enhanced the mechanical stability of the electrode.Compared to the conventional bar-coated electrode with the same thickness of 155μm(delivered a discharge capacity of 16 mAh g^(−1) at the rate of 3 C),the stamped low-tortuosity LiFePO_(4) electrode delivered 101 mAh g^(−1) capacity.Additionally,water was employed as a solvent in this study.Owing to its eco-friendliness,high scalability,and minimal waste generation,this novel stamping technique inspire a new method for the industrial-level efficient roll to roll fabrication of fast-charge electrodes.
文摘Polycystic ovary syndrome(PCOS)is an endocrine disorder caused by hypothalamic-pituitary-ovarian(HPO)axis dysfunction.In the field of gynecology and reproduction,PCOS has emerged as both a research hot spot and a challenging area of study.According to Chinese medicine,this disease is related to kidney deficiency,phlegm and dampness obstruction,blood stasis and interconnection,Chong pulse impassability,the lack of Ren pulse,and the loss of uterine nourishment,all of which affect the normal development and maturation of eggs as well as the duration at which menstrual blood stores.In this paper,based on the theoretical basis of“liver collects blood,regulates the flow of qi,and is the master of drainage,”we explore the rationality of the treatment of this disease from the perspective of“liver and kidney have the same origin”and the development of PCOS-related infertility in relation to dysfunctional internal organs.We also explore the feasibility of treatment from the perspective of“liver and kidney homology,”expand the ideas for treatment,as well as develop and innovate the application of organ identification in PCOS in relation to infertility.
文摘Secondary batteries have been widely developed and used in various fields,such as large-scale energy storage,portable electronics,and electric vehicles.Carbon-based materials have attracted considerable attention due to their abundance,environmental friendliness,tunable structure,and excellent chemical stability.Beyond the commercial carbon for batteries and supercapacitors,many studies focused on advanced and multifunctional carbon with various structures for electrochemical energy storage.This review summarizes the zero-to three-dimensional carbon-based materials and reviews their various electrochemical applications based on their structural characteristics.The importance of carbon structures and the relationship between materials'structures and electrochemical performance are discussed.Then,the prospects and potential challenges of using advanced carbon to formulate designs and develop novel carbonaceous materials with high electrochemical performance are further discussed.
基金Supported by National Science and Technology Major Project (2018ZX08020001-006)。
文摘[Objectives] This study was conducted to investigate the possibility of screening for herbicide resistance in the early stage of rapes growth. [Methods] Eight treatments were set for a herbicide concentration experiment. [Results] Rape sprouts were highly sensitive to the herbicide glyphosate, and even a very low concentration of glyphosate solution(187 mg/L) was sufficient to kill most of the rape seedlings, while the genetically modified herbicide-tolerant rape could tolerate higher concentrations of the herbicide. Low concentrations of glyphosate could be used for screening at the sprout stage, and the results of herbicide-tolerance screening were consistent with PCR testing. [Conclusions] This study lays a technical and material foundation for accelerating the cultivation of new herbicide-resistant rape varieties suitable for rapeseed production areas in the lower reaches of the Yangtze River.
基金Social Development Science and Technology Project(Project name:Clinical study on the effect of electroacupuncture combined with walking through the meridian on body mass index,glucose metabolism and reproductive endocrine in patients with obese polycystic ovary syndromeProject no.:2016SF-362)Special Project of Natural Science(Project name:Association of endometrial precancerous lesions with insulin resistance and adiponectin based on high incidence of diabetes mellitus,Project no.:13JK0800)。
文摘Objective:To systematically evaluate the efficacy and safety of didroxyprogesterone combined with progesterone in the treatment of luteal insufficiency abortion.Methods:We searched CNKI database,VIP database,Wanfang database,PubMed database,EMBASE database and Cochrane library database for literatures on the treatment of luteal insufficiency-induced abortion with didroxyprogesterone and progesterone.Meta-analysis was performed using Revman 5.3 software after literature extraction and further quality evaluation.Results:Ten randomized controlled trial-related articles that describe studies on a total of 1145 patients,570 in the combination group and 575 in the control group,were included.The results of meta-analysis showed that combination therapy could improve the effective rate of fetal protection(OR=0.14,95%CI[0.07,0.27],P<0.00001).The safety of the combination group was significantly higher than that of the control group(OR=3.09,95%CI[1.13,8.48],P=0.03).Conclusion:To sum up,compared with the control group,the combination of progesterone and progesterone is more effective and safer in the treatment of luteal insufficiency abortion.However,the sample size of the data is relatively small and the quality of the literature is low.This conclusion still needs to be further verified in high-quality randomized controlled trials that involve large samples.
基金Social development science and technology project:2016SF-362 Clinical study on the effect of electroacupuncture combined with walking through meridians on body mass index,glucose metabolism and reproductive endocrine in patients with obese polycystic ovary syndrome.
文摘Polycystic ovary syndrome(PCOS)is a disease with reproductive dysfunction and abnormal endocrine metabolism.It is characterized by hyperandrogenism,insulin resistance(IR)and persistent anovulation.At present,the pathogenesis and pathological mechanism of PCOS are still unclear,and there is no unified standard for the diagnosis and treatment of PCOS locally nor abroad.It is still a famous and difficult problem to explore the pathogenesis of PCOS and seek effective prevention and treatment methods.
文摘Autophagy is a self-protection mechanism of the body,and also an important physiological process for cells to maintain internal environment stability.Studies have shown that the degree of autophagy damage is positively correlated with the expression of oncogenes,and the expression of oncogenes is closely related to cervical HPV infection,so the control of autophagy ability can interfere with cervical HPV virus infection.Traditional Chinese medicine believes that dampness-heat evil down,can damage and Chong Ren cell.The author believes that autophagy damage and the theory of dampness-heat injection in cervical HPV infection have similar pathogenic mechanism,and explores the prevention and treatment of autophagy and cervical HPV infection based on the theory of traditional Chinese medicine dampness-heat injection,in attempt to provide a new treatment for clinical prevention and treatment.
文摘Traditional medicine believes that emotional,room labor and other factors lead to the lack of blood circulation after the weather,and the consumption of Yin blood is too much,which can lead to the deficiency of blood essence.Over time,the deficiency of menstrual blood can not nourish the kidney essence,leading to abnormal pregnancy.The liver is congenital for women,and the kidney is congenital.The disharmony of liver and kidney is the key factor of women's disease.Starting from the"homology of Yi and GUI",this paper analyzes the main etiology and pathogenesis of the disease from three aspects:deficiency of blood essence,imbalance of Zang and Xie,and Yin not controlling Yang.Following the principle of simultaneous treatment of liver and kidney,starting from the three methods of "regulating and tonifying liver and kidney,tonifying kidney and activating blood circulation,and balancing yin and Yang",the liver and kidney are reconciled,and pregnancy is sometimes the best choice.The main purpose is to benefit PCOS patients.
基金Shaanxi Province Social Development Science and Technology Project(2016SF-362)。
文摘The main cause of infertility in elderly women is poor ovarian function,decreased quality and number of oocytes,which ultimately leads to poor fertility.Low ovarian function is the most difficult point in the research of reproductive medicine and reproductive health.At present,the treatment of integrated traditional Chinese and Western medicine has gradually achieved results.Western medicine mainly regulates endocrine and assisted reproductive treatment by supplementing estrogen and progesterone,while traditional Chinese medicine(TCM)mainly focuses on invigorating the kidney,adding and subtracting according to the syndrome.The treatment effect of TCM or western medicine alone is not significant.Many clinical observations show that integrated TCM and western medicine focuses on the specialties of western medicine,which not only makes up for the insufficiency of the slow action of TCM,but also improves its clinical efficacy when combined with western medicine.Based on domestic and foreign research,this article summarizes the treatment of infertility in elderly women with integrated TCM and western medicine.
文摘Porous carbon materials are widely used in particulate forms for energy applications such as fuel cells, batteries, and （super） capacitors. To better hold the particles together, polymeric additives are utilized as binders, which not only increase the weight and volume of the devices, but also cause adverse side effects. We developed a wood-derived, free-standing porous carbon electrode and successfully applied it as a cathode in Li-O2 batteries. The spontaneously formed hierarchical porous structure exhibits good performance in facilitating the mass transport and hosting the discharge products of Li202. Heteroatom （N） doping further improves the catalytic activity of the carbon cathode with lower overpotential and higher capacity. Overall, the Li-O2 battery based on the new carbon cathode affords a stable energy efficiency of 65% and can be operated for 20 cycles at a discharge depth of 70%. The wood-derived free-standing carbon represents a new, unique structure for energy applications.
基金the National Science Foundation Electrochemical Systems Program at the Division of Chemical,Bioengineering,Environmental,and Transport Systems(CBET-1924534)and Rogers Corporation,United States are acknowledged.
文摘Recent advances in next-generation energy storage devices have focused on flexible and wearable all-solid-state lithium batteries(ASSLBs),mainly because of their advantages in terms of safety and extensive applications.Among various tech-nologies for the preparation of flexible electrodes,electrospinning is a straightforward operation and cost-effective mean for the facile fabrication of flexible nanofibers and the versatile design of nanofiber structure.Herein,current technologies for engineering electrospun nanofiber structures and their state-of-the-art implementation in flexible ASSLBs are reviewed.First,current strategies for nanofiber structural design,including advances in high-specific surface area,superior mechanical flexibility,and various nanostructures,are systematically discussed.Subsequently,the utilization of electrospun nanofibers in ASSLBs is reviewed.Electrospinning of flexible and highly ion-conductive solid-state electrolytes(SSEs)is emphasized,and current nanofiber structural designs for SSEs and electrodes for ASSLBs are introduced.Despite these advances,there have not been enough studies of the integration of versatile electrospinning techniques in nanofiber structural design for both SSEs and electrodes.In the final section,promising pathways to implement versatile electrospinning in flexible ASSLBs with superior electrochemical performance and stable cycling properties are discussed.Thus,this review provides a holistic overview of the state of the art of electrospinning for high-performance flexible ASSLBs,which could safely power next-generation flexible devices.
基金This manuscript was authored in part by UT-Battelle LLC under contract DE-AC05-00OR22725 with DOE.
文摘Considering the growing concerns about natural resource depletion,energy inequality,and climate crises,biomassderived materials—the most abundant organic matter on the planet—have received a lot of attention as a potential alternative to petroleum-based plastics.Herbaceous biomasses and extracted cellulose have recently been extensively used in the development of high-performance and multifunctional materials.Herbaceous biomass has sparked interest due to its species diversity,abundance,low cost,lightweight,and sustainability.This review discusses the structure versus property relationships of various sources of herbaceous biomasses(e.g.,sugarcane,straw,and bamboo)and their extracted biomaterials,as well as the latest emerging applications from macro-and microscales to nanoscales.High-strength structural materials,porous carbon materials,multichannel materials,and flexible materials are examples of these applications,which include sustainable electronics,environmentally friendly energy harvesting,smart materials,and biodegradable structural buildings.
基金the financial startup support and Tier 1 award from Northeastern University。
文摘Element sulfur in nature is an insulating solid.While it has been tested that one-dimensional sulfur chain is metallic and conducting,the investigation on two-dimensional sulfur remains elusive.We report that molybdenum disulfide layers are able to serve as the nanotemplate to facilitate the formation of two-dimensional sulfur.Density functional theory calculations suggest that confined inbetween layers of molybdenum disulfide,sulfur atoms are able to form two-dimensional triangular arrays that are highly metallic.As a result,these arrays contribute to the high conductivity and metallic phase of the hybrid structures of molybdenum disulfide layers and two-dimensional sulfur arrays.The experimentally measured conductivity of such hybrid structures reaches up to 223 S/m.Multiple experimental results,including X-ray photoelectron spectroscopy(XPS),transition electron microscope(TEM),selected area electron diffraction(SAED),agree with the computational insights.Due to the excellent conductivity,the current density is linearly proportional to the scan rate until 30,000 mV s^(−1) without the attendance of conductive additives.Using such hybrid structures as electrode,the two-electrode supercapacitor cells yield a power density of 10^(6) Wh kg^(−1) and energy density ~47.5 Wh kg^(−1) in ionic liquid electrolytes.Our findings offer new insights into using two-dimensional materials and their Van der Waals heterostructures as nanotemplates to pattern foreign atoms for unprecedented material properties.
