Lead-free halide perovskite materials possess low toxicity,broadband luminescence and robust stability compared with conventional lead-based perovskites,thus holding great promise for eyes-friendly white light LEDs.Ho...Lead-free halide perovskite materials possess low toxicity,broadband luminescence and robust stability compared with conventional lead-based perovskites,thus holding great promise for eyes-friendly white light LEDs.However,the traditionally used preparation methods with a long period and limited product yield have curtailed the commercialization of these materials.Here we introduce a universal hydrochloric acid-assistant powder-to-powder strategy which can accomplish the goals of thermal-,pressure-free,eco-friendliness,short time,low cost and high product yield,simultaneously.The obtained Cs_(2)Na_(0.9)Ag_(0.1)In_(0.95)Bi_(0.05)Cl_(6)microcrystals exhibit bright self-trapped excitons emission with quantum yield of(98.3±3.8)%,which could retain(90.5±1.3)%and(96.8±0.8)%after continuous heating or ultraviolet-irradiation for 1000 h,respectively.The phosphor converted-LED exhibited near-unity conversion efficiency from ultraviolet chip to self-trapped excitons emission at~200 mA.Various ions doping(such as Cs_(2)Na_(0.9)Ag_(0.1)InCl_(6):Ln^(3+))and other derived lead-free perovskite materials(such as Cs_(2)ZrCl_(6)and Cs_(4)MnBi_(2)Cl_(12))with high luminous performance are all realized by our proposed strategy,which has shown excellent availability towards commercialization.展开更多
The metal—organic frameworks(MOFs)are expected as ideal biomimetic enzymes for colorimetric glucose detection because of their large surface areas,well defined pore structures,tunable chemical composition,and multi-f...The metal—organic frameworks(MOFs)are expected as ideal biomimetic enzymes for colorimetric glucose detection because of their large surface areas,well defined pore structures,tunable chemical composition,and multi-functional sites.However,the intrinsically chemical instability and low mimetic enzyme activity of MOFs hinder the application of them in imitating the enzyme reactions.In this work,we demonstrated a metal-MOF synergistic catalysis strategy,by loading Pt nanoparticles(Pt NPs)on MIL-88B-NH2(Fe-MOF)to increase peroxidase-like activity for the detection of glucose.The induced electrons transfer from Pt atom to Fe atom accelerated the redox cycling of Fe^(3+)/Fe^(2+),improved the overall efficiency of the peroxidase-like reaction,and enabled the efficient and robust colorimetric glucose detection,which was proved by both experiments and density functional theory(DFT)calculation.Additionally,the sensitivity and chemical stability of this synergistic effect strategy to detect the glucose are not affected by the complex external factors,which represented a great potential in fast,easy,sensitive,and specific recognition of clinical diabetes.展开更多
Regulation of chemical composition and nanostructure, such as the introduction of dopant into two-dimensional nanomaterials, is a general and valid strategy for the efficient electrocatalyst design. In this work, Co_(...Regulation of chemical composition and nanostructure, such as the introduction of dopant into two-dimensional nanomaterials, is a general and valid strategy for the efficient electrocatalyst design. In this work, Co_(4)S_(3)/Co_(9)S_(8) nanosheets, with an ultrathin layer structure, were successfully synthesized via an efficient solvothermal process combined with ultrasonic exfoliation. Different metal ions (M = Fe^(3+), Cr^(3+), Mn^(2+) and Ni^(2+)) were then doped by a simple cation exchange method and the effects of different dopants on the OER activities of Co_(4)S_(3)/Co_(9)S_(8) NS were further investigated in alkaline media. The corresponding results implied that M-doped Co_(4)S_(3)/Co_(9)S_(8) NS (M = Fe^(3+), Cr^(3+), Mn^(2+) and Ni^(2+)) exhibited different electrocatalytic properties. Evidenced by XPS spectra, the different OER activities were mainly aroused by the redistribution of charge at the interface due to an electronic interaction between the doped metal ions and Co_(4)S_(3)/Co_(9)S_(8) NS.展开更多
How water layer adsorbed on solid surface under ambient conditions affects the interfacial friction is a fundamental question for understanding the friction and lubrication phenomena in practical system.We investigate...How water layer adsorbed on solid surface under ambient conditions affects the interfacial friction is a fundamental question for understanding the friction and lubrication phenomena in practical system.We investigate the formation of ice-like(IL)water layers on the hydrophobic surface of graphite with partially covered MoO_(3)nanoflakes(NFs)using atomic force microscopy(AFM)based techniques.The IL water layers are found surrounding the MoO_(3)NFs and also intercalated at the MoO_(3)/graphite interface,as proved by thickness measurements as well as local adhesion force and surface potential mappings.AFM manipulations carried out on MoO_(3)NFs on graphite show that the presence of the IL water layers increases the frictional resistance of the interface.Comparing the results on continuous and discontinuous IL water layers,we can identify the different sliding interfaces in the two scenarios.The increased friction for MoO_(3)NFs sliding on graphite with an intercalated water layer is attributed to the energy dissipation originated from the metastable nature of the IL layers.展开更多
基金supported by the National Natural Science Foundation of China(22005152,22275101).
文摘Lead-free halide perovskite materials possess low toxicity,broadband luminescence and robust stability compared with conventional lead-based perovskites,thus holding great promise for eyes-friendly white light LEDs.However,the traditionally used preparation methods with a long period and limited product yield have curtailed the commercialization of these materials.Here we introduce a universal hydrochloric acid-assistant powder-to-powder strategy which can accomplish the goals of thermal-,pressure-free,eco-friendliness,short time,low cost and high product yield,simultaneously.The obtained Cs_(2)Na_(0.9)Ag_(0.1)In_(0.95)Bi_(0.05)Cl_(6)microcrystals exhibit bright self-trapped excitons emission with quantum yield of(98.3±3.8)%,which could retain(90.5±1.3)%and(96.8±0.8)%after continuous heating or ultraviolet-irradiation for 1000 h,respectively.The phosphor converted-LED exhibited near-unity conversion efficiency from ultraviolet chip to self-trapped excitons emission at~200 mA.Various ions doping(such as Cs_(2)Na_(0.9)Ag_(0.1)InCl_(6):Ln^(3+))and other derived lead-free perovskite materials(such as Cs_(2)ZrCl_(6)and Cs_(4)MnBi_(2)Cl_(12))with high luminous performance are all realized by our proposed strategy,which has shown excellent availability towards commercialization.
基金This work was supported by National Natural Science Foundation of China(Nos.21705117,21575115,21904095,and 22004089)Program of Tianjin Science and Technology Major Project and Engineering(No.19ZXYXSY00090)+3 种基金the Program for Chang Jiang Scholars and Innovative Research Team,Ministry of Education,China(No.IRT-16R61)Special Fund Project for the Central Government to Guide Local Science and Technology Development(2020)the Applied Fundamental Research Fund of Sichuan Province(No.2019YJ0169)the new scholar fund of UESTC.
文摘The metal—organic frameworks(MOFs)are expected as ideal biomimetic enzymes for colorimetric glucose detection because of their large surface areas,well defined pore structures,tunable chemical composition,and multi-functional sites.However,the intrinsically chemical instability and low mimetic enzyme activity of MOFs hinder the application of them in imitating the enzyme reactions.In this work,we demonstrated a metal-MOF synergistic catalysis strategy,by loading Pt nanoparticles(Pt NPs)on MIL-88B-NH2(Fe-MOF)to increase peroxidase-like activity for the detection of glucose.The induced electrons transfer from Pt atom to Fe atom accelerated the redox cycling of Fe^(3+)/Fe^(2+),improved the overall efficiency of the peroxidase-like reaction,and enabled the efficient and robust colorimetric glucose detection,which was proved by both experiments and density functional theory(DFT)calculation.Additionally,the sensitivity and chemical stability of this synergistic effect strategy to detect the glucose are not affected by the complex external factors,which represented a great potential in fast,easy,sensitive,and specific recognition of clinical diabetes.
基金supported by the National Natural Science Foundation of China (Nos. 21671179, 21705117, 21904120 and62073299)Henan Province Science and Technology Programs (Nos.202102210045 and 212102310858)Program for Innovative Research Team (in Science and Technology) in University of Henan Province (No. 20IRTSTHN017)。
文摘Regulation of chemical composition and nanostructure, such as the introduction of dopant into two-dimensional nanomaterials, is a general and valid strategy for the efficient electrocatalyst design. In this work, Co_(4)S_(3)/Co_(9)S_(8) nanosheets, with an ultrathin layer structure, were successfully synthesized via an efficient solvothermal process combined with ultrasonic exfoliation. Different metal ions (M = Fe^(3+), Cr^(3+), Mn^(2+) and Ni^(2+)) were then doped by a simple cation exchange method and the effects of different dopants on the OER activities of Co_(4)S_(3)/Co_(9)S_(8) NS were further investigated in alkaline media. The corresponding results implied that M-doped Co_(4)S_(3)/Co_(9)S_(8) NS (M = Fe^(3+), Cr^(3+), Mn^(2+) and Ni^(2+)) exhibited different electrocatalytic properties. Evidenced by XPS spectra, the different OER activities were mainly aroused by the redistribution of charge at the interface due to an electronic interaction between the doped metal ions and Co_(4)S_(3)/Co_(9)S_(8) NS.
基金This work was supported by the Project of the Ministry of Science and Technology of China(No.2017YFA0205000)the National Natural Science Foundation of China(Nos.51802053,21790353,21721002)the Strategic Priority Research Program of Chinese Academy of Sciences(No.XDB36000000).
文摘How water layer adsorbed on solid surface under ambient conditions affects the interfacial friction is a fundamental question for understanding the friction and lubrication phenomena in practical system.We investigate the formation of ice-like(IL)water layers on the hydrophobic surface of graphite with partially covered MoO_(3)nanoflakes(NFs)using atomic force microscopy(AFM)based techniques.The IL water layers are found surrounding the MoO_(3)NFs and also intercalated at the MoO_(3)/graphite interface,as proved by thickness measurements as well as local adhesion force and surface potential mappings.AFM manipulations carried out on MoO_(3)NFs on graphite show that the presence of the IL water layers increases the frictional resistance of the interface.Comparing the results on continuous and discontinuous IL water layers,we can identify the different sliding interfaces in the two scenarios.The increased friction for MoO_(3)NFs sliding on graphite with an intercalated water layer is attributed to the energy dissipation originated from the metastable nature of the IL layers.
基金supported by the National Natural Science Foundation of China(21705117,21904095,22001193,22174110)the Elite Scholar Program of Tianjin University(2019XRG-0065)+2 种基金the Program of Tianjin Science and Technology Major Project and Engineering(19ZXYXSY00090)the Program for Chang Jiang Scholars and Innovative Research Team,Ministry of Education,China(IRT-16R61)the Special Fund Project for the Central Government to Guide Local Science and Technology Development(2020)。