Memristors are a new type of circuit element with a resistance that is tunable to discrete levels by a voltage/current and sustainable after removal of power,allowing for low-power computation and multilevel informati...Memristors are a new type of circuit element with a resistance that is tunable to discrete levels by a voltage/current and sustainable after removal of power,allowing for low-power computation and multilevel information storage.Many organic-inorganic lead perovskites are reported to demonstrate memristive behavior,but few have been considered for use as a multilevel memory;also,their potential application has been hindered by the toxicity of lead ions.In this article,lead-free perovskite MASnBr3 was utilized in memristors for quaternary information storage.Indium tin oxide(ITO)/MASnBr3/Au memristors were fabricated and showed reliable memristive switching with well-separated ON/OFF states of a maxima resistance ratio of 102 to 103.More importantly,four resistive states can be distinguished and repeatedly written/read/erased with a retention time of 104 seconds and an endurance of 104 pulses.By investigating the current-electrode area relationship,Br distribution in the ON/OFF states by in situ Raman and scanning electron microscopy,and temperaturedependent current decay,the memristive behavior was explicitly attributed to the forming/breaking of conductive filaments caused by the migration of Br−under an electric field.In addition,poly(ethylene terephthalate)-ITO/MASnBr3/Au devices were found to retain their multiresistance state behavior after being bent for 1000 times,thus demonstrating good device flexibility.Our results will inspire more lead-free perovskite work for multilevel information storage,as well as other memristor-based electronics.展开更多
Left and right-handed helical barium titanate nanotubes are prepared with the impregnation of Ba（OH）2 into single-handed helical titania nanotubes.Wide angle X-ray diffraction pattern and transmission electron micro...Left and right-handed helical barium titanate nanotubes are prepared with the impregnation of Ba（OH）2 into single-handed helical titania nanotubes.Wide angle X-ray diffraction pattern and transmission electron microscopy image indicate that they are constructed by nanoparticles with a partially crystalline structure.The diffuse reflertance circular dichroism spectra indicate that they exhibit optical activity which was proposed to originate from chiral defects on the inner surfaces of the nanotubes.Both the dielectric constant and tanδ decrease with increasing the frequency.At 10 and 100 Hz,one dielectric constant peak at 9.6℃ and one tanδ peak at 5.0℃ are observed at -120℃ to 180℃.展开更多
基金Major Research Project of Natural Scientific Research Foundation of the Higher Education Institutions in Jiangsu Province,Grant/Award Number:17KJA150010Natural Science Foundation of China,Grant/Award Numbers:21978185,21938006,21603158Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)。
文摘Memristors are a new type of circuit element with a resistance that is tunable to discrete levels by a voltage/current and sustainable after removal of power,allowing for low-power computation and multilevel information storage.Many organic-inorganic lead perovskites are reported to demonstrate memristive behavior,but few have been considered for use as a multilevel memory;also,their potential application has been hindered by the toxicity of lead ions.In this article,lead-free perovskite MASnBr3 was utilized in memristors for quaternary information storage.Indium tin oxide(ITO)/MASnBr3/Au memristors were fabricated and showed reliable memristive switching with well-separated ON/OFF states of a maxima resistance ratio of 102 to 103.More importantly,four resistive states can be distinguished and repeatedly written/read/erased with a retention time of 104 seconds and an endurance of 104 pulses.By investigating the current-electrode area relationship,Br distribution in the ON/OFF states by in situ Raman and scanning electron microscopy,and temperaturedependent current decay,the memristive behavior was explicitly attributed to the forming/breaking of conductive filaments caused by the migration of Br−under an electric field.In addition,poly(ethylene terephthalate)-ITO/MASnBr3/Au devices were found to retain their multiresistance state behavior after being bent for 1000 times,thus demonstrating good device flexibility.Our results will inspire more lead-free perovskite work for multilevel information storage,as well as other memristor-based electronics.
基金supported by the Priority Academic Program Development of Jiangsu High Education Institutions(PAPD)
文摘Left and right-handed helical barium titanate nanotubes are prepared with the impregnation of Ba（OH）2 into single-handed helical titania nanotubes.Wide angle X-ray diffraction pattern and transmission electron microscopy image indicate that they are constructed by nanoparticles with a partially crystalline structure.The diffuse reflertance circular dichroism spectra indicate that they exhibit optical activity which was proposed to originate from chiral defects on the inner surfaces of the nanotubes.Both the dielectric constant and tanδ decrease with increasing the frequency.At 10 and 100 Hz,one dielectric constant peak at 9.6℃ and one tanδ peak at 5.0℃ are observed at -120℃ to 180℃.
