MnO_(2) emerges as a promising cathode material for aqueous zinc-ion batteries(AZIBs)due to its high theoretical capacity and ideal working voltage.However,inherent limitations in low electrical conductivity and struc...MnO_(2) emerges as a promising cathode material for aqueous zinc-ion batteries(AZIBs)due to its high theoretical capacity and ideal working voltage.However,inherent limitations in low electrical conductivity and structural instability restrict its widespread application.Herein,we fabricated layered δ-MnO_(2) and introduced Cu and Ce metal ions for structural regulation,thus constructing a δ/a-MnO_(2) heterostructure within the δ-MnO_(2) matrix,forming a heterointerface that simultaneously enhances the electrical conductivity and structural stability of the material.In this system,Cu^(2+)acts as a catalyst,promoting the reduction of high-valent Mn to Mn^(2+)and enabling local two-electron transfer,which significantly increases the discharge specific capacity of MnO_(2).For Ce^(3+),it functions as a structural regulator,inducing the partial transformation of δ-MnO_(2) to a-MnO_(2) and forming the δ/a-MnO_(2) heterostructure.Further supported by density functional theory(DFT)calculations and in-situ characterization results,the heterointerface between a-MnO_(2) andδ-MnO_(2) generates an internal electric field due to the difference in Fermi levels.This not only effectively enhances the electron transfer capability but also significantly improves structural stability.Benefiting from these advantages,the Cu,Ce co-incorporated MnO_(2)(CCMO)cathode delivers a high discharge capacity of 455.4 mAh g^(-1)at 0.2 A g^(-1)and maintains 191.2 mAh g^(-1)specific capacity after 1500 cycles with 95%capacity retention at 2 A g^(-1),which is significantly better than non-doped MnO_(2).This strategy of structural regulation and heterostructure construction using vip ions offers a new approach for developing high-performance Mn-based cathode materials for AZIBs.展开更多
[Objectives]The study aimed to evaluate the safety of Tongchui Baihua capsule.[Methods]Long-term toxicology experiment was adopted,the rats were randomly divided into control group and administration group according t...[Objectives]The study aimed to evaluate the safety of Tongchui Baihua capsule.[Methods]Long-term toxicology experiment was adopted,the rats were randomly divided into control group and administration group according to the gender of male and female;the drug administration group was given different doses of Tongchui Baihua capsules,and the drug was administered by continuous gavage for 13 weeks;the general conditions,haematological indexes,blood biochemical indexes and visceral coefficients of the rats were detected at the 13th week and 4 weeks after the drug withdrawal respectively,and the toxic symptoms were observed.[Results]The rats were given Tongchui Baihua capsule in different doses by gavage for 13 weeks,and no obvious toxicity was observed in weight,haematological indexes,blood biochemical indexes and histopathology.[Conclusions]Under the condition of long-term toxicity experiment,Tongchui Baihua capsule was safe for rats.展开更多
Because of profound applications of two-dimensional molybdenum disulfide(MoS_(2))and its heterostructures in electronics,its thermal stability has been spurred substantial interest.We employ a precision muffle furnace...Because of profound applications of two-dimensional molybdenum disulfide(MoS_(2))and its heterostructures in electronics,its thermal stability has been spurred substantial interest.We employ a precision muffle furnace at a series of increasing temperatures up to 340℃to study the oxidation behavior of continuous MoS_(2)films by either directly growing mono-and fewlayer MoS_(2)on SiO_(2)/Si substrate,or by mechanically transferring monolayer MoS_(2)or hexagonal boron nitride(h-BN)onto monolayer MoS_(2)substrate.Results show that monolayer MoS_(2)can withstand high temperature at 340℃with less oxidation while the few-layer MoS_(2)films are completely oxidized just at 280℃,resulting from the growth-induced tensile strain in few-layer MoS_(2).When the tensile strain of films is released by transfer method,the stacked few-layer MoS_(2)films exhibit superior thermal stability and typical layer-by-layer oxidation behavior at similarly high temperature.Counterintuitively,for the MoS_(2)/h-BN heterostructure,the h-BN film itself stacked on top is not damaged and forms many bubbles at 340℃,whereas the underlying monolayer MoS_(2)film is oxidized completely.By comprehensively using various experimental characterization and molecular dynamics calculations,such anomalous oxidation behavior of MoS_(2)/h-BN heterostructure is mainly due to the increased tensile strain in MoS_(2)film at elevated temperature.展开更多
基金supported by the National Natural Science Foundation of China(no.52574348)the Natural Science Foundation of Hebei Province(nos.E2024501010 and B2024501004)+3 种基金the Shijiazhuang Basic Research Project(no.241790667A)the Fundamental Research Funds for the Central Universities(no.N2423013)the National College Students Innovation and Entrepreneurship Training Program(no.202419145017)the Performance Subsidy Fund for Key Laboratory of Dielectric,Electrolyte Functional Material Hebei Province(no.22567627H)。
文摘MnO_(2) emerges as a promising cathode material for aqueous zinc-ion batteries(AZIBs)due to its high theoretical capacity and ideal working voltage.However,inherent limitations in low electrical conductivity and structural instability restrict its widespread application.Herein,we fabricated layered δ-MnO_(2) and introduced Cu and Ce metal ions for structural regulation,thus constructing a δ/a-MnO_(2) heterostructure within the δ-MnO_(2) matrix,forming a heterointerface that simultaneously enhances the electrical conductivity and structural stability of the material.In this system,Cu^(2+)acts as a catalyst,promoting the reduction of high-valent Mn to Mn^(2+)and enabling local two-electron transfer,which significantly increases the discharge specific capacity of MnO_(2).For Ce^(3+),it functions as a structural regulator,inducing the partial transformation of δ-MnO_(2) to a-MnO_(2) and forming the δ/a-MnO_(2) heterostructure.Further supported by density functional theory(DFT)calculations and in-situ characterization results,the heterointerface between a-MnO_(2) andδ-MnO_(2) generates an internal electric field due to the difference in Fermi levels.This not only effectively enhances the electron transfer capability but also significantly improves structural stability.Benefiting from these advantages,the Cu,Ce co-incorporated MnO_(2)(CCMO)cathode delivers a high discharge capacity of 455.4 mAh g^(-1)at 0.2 A g^(-1)and maintains 191.2 mAh g^(-1)specific capacity after 1500 cycles with 95%capacity retention at 2 A g^(-1),which is significantly better than non-doped MnO_(2).This strategy of structural regulation and heterostructure construction using vip ions offers a new approach for developing high-performance Mn-based cathode materials for AZIBs.
文摘[Objectives]The study aimed to evaluate the safety of Tongchui Baihua capsule.[Methods]Long-term toxicology experiment was adopted,the rats were randomly divided into control group and administration group according to the gender of male and female;the drug administration group was given different doses of Tongchui Baihua capsules,and the drug was administered by continuous gavage for 13 weeks;the general conditions,haematological indexes,blood biochemical indexes and visceral coefficients of the rats were detected at the 13th week and 4 weeks after the drug withdrawal respectively,and the toxic symptoms were observed.[Results]The rats were given Tongchui Baihua capsule in different doses by gavage for 13 weeks,and no obvious toxicity was observed in weight,haematological indexes,blood biochemical indexes and histopathology.[Conclusions]Under the condition of long-term toxicity experiment,Tongchui Baihua capsule was safe for rats.
基金the National Natural Science Foundation of China(No.52005489)Ningbo 3315 Innovation Team(No.2020A-03-C)+1 种基金the China Postdoctoral Science Fund(Nos.2021T140685 and 2019M662126)the Natural Science Foundation of Zhejiang Province(No.LR20E050001).
文摘Because of profound applications of two-dimensional molybdenum disulfide(MoS_(2))and its heterostructures in electronics,its thermal stability has been spurred substantial interest.We employ a precision muffle furnace at a series of increasing temperatures up to 340℃to study the oxidation behavior of continuous MoS_(2)films by either directly growing mono-and fewlayer MoS_(2)on SiO_(2)/Si substrate,or by mechanically transferring monolayer MoS_(2)or hexagonal boron nitride(h-BN)onto monolayer MoS_(2)substrate.Results show that monolayer MoS_(2)can withstand high temperature at 340℃with less oxidation while the few-layer MoS_(2)films are completely oxidized just at 280℃,resulting from the growth-induced tensile strain in few-layer MoS_(2).When the tensile strain of films is released by transfer method,the stacked few-layer MoS_(2)films exhibit superior thermal stability and typical layer-by-layer oxidation behavior at similarly high temperature.Counterintuitively,for the MoS_(2)/h-BN heterostructure,the h-BN film itself stacked on top is not damaged and forms many bubbles at 340℃,whereas the underlying monolayer MoS_(2)film is oxidized completely.By comprehensively using various experimental characterization and molecular dynamics calculations,such anomalous oxidation behavior of MoS_(2)/h-BN heterostructure is mainly due to the increased tensile strain in MoS_(2)film at elevated temperature.
