Flexoelectric effect describes the electromechanical coupling between the strain gradient and its internal polarization in all dielectrics.Despite this universality,the resulting flexoelectric field remains small at t...Flexoelectric effect describes the electromechanical coupling between the strain gradient and its internal polarization in all dielectrics.Despite this universality,the resulting flexoelectric field remains small at the macroscopic level.However,in nanosystems,the size-dependent effect of flexoelectricity becomes increasingly significant,leading to a notable flexoelectric field that can strongly influence the material’s physical properties.This review aims to explore the flexoelectric effect specifically at the nanoscale.We achieve this by examining strain gradients generated through two distinct methods:internal inhomogeneous strain and external stimulation.In addition,advanced synthesis techniques are utilized to enhance the properties and functionalities associated with flexoelectricity.Furthermore,we delve into other coupled phenomena observed in thin films,including the coupling and utilization of flexomagnetic and flexophotovoltaic effects.This review presents the latest advancements in these areas and highlights their role in driving further breakthroughs in the field of flexoelectricity.展开更多
Flexoelectricity refers to the mechanical-electro coupling between strain gradient and electric polarization, and conversely, the electro-mechanical coupling between electric field gradient and mechanical stress. This...Flexoelectricity refers to the mechanical-electro coupling between strain gradient and electric polarization, and conversely, the electro-mechanical coupling between electric field gradient and mechanical stress. This unique effect shows a promising size effect which is usually large as the material dimension is shrunk down. Moreover, it could break the limitation of centrosymmetry, and has been found in numerous kinds of materials which cover insulators, liquid crystals, biological materials, and semiconductors. In this review, we will give a brief report about the recent discoveries in flexoelectricity, focusing on the flexoelectric materials and their applications. The theoretical developments in this field are also addressed. In the end, the perspective of flexoelectricity and some open questions which still remain unsolved are commented upon.展开更多
The resistive switching(RS)mechanism of hybrid organic–inorganic perovskites has not been clearly understood until now.A switchable diode-like RS behavior in MAPbBr3 single crystals using Au(or Pt)symmetric electrode...The resistive switching(RS)mechanism of hybrid organic–inorganic perovskites has not been clearly understood until now.A switchable diode-like RS behavior in MAPbBr3 single crystals using Au(or Pt)symmetric electrodes is reported.Both the high resistance state(HRS)and low resistance state(LRS)are electrode-area dependent and light responsive.We propose an electric-fielddriven inner p–n junction accompanied by a trap-controlled space-charge-limited conduction(SCLC)conduction mechanism to explain this switchable diode-like RS behavior in MAPbBr_(3) single crystals.展开更多
基金supported by the National Natural Science Foundation of China(Nos.51962020,12174174)Support from the Natural Science Foundation of Jiangxi Province(No.20212ACB214011)was also acknowledged.
文摘Flexoelectric effect describes the electromechanical coupling between the strain gradient and its internal polarization in all dielectrics.Despite this universality,the resulting flexoelectric field remains small at the macroscopic level.However,in nanosystems,the size-dependent effect of flexoelectricity becomes increasingly significant,leading to a notable flexoelectric field that can strongly influence the material’s physical properties.This review aims to explore the flexoelectric effect specifically at the nanoscale.We achieve this by examining strain gradients generated through two distinct methods:internal inhomogeneous strain and external stimulation.In addition,advanced synthesis techniques are utilized to enhance the properties and functionalities associated with flexoelectricity.Furthermore,we delve into other coupled phenomena observed in thin films,including the coupling and utilization of flexomagnetic and flexophotovoltaic effects.This review presents the latest advancements in these areas and highlights their role in driving further breakthroughs in the field of flexoelectricity.
基金supported by the National Natural Science Foundation of China under Grant Nos. 11574126 and 11604135the Natural Science Foundation of Jiangxi Province (No. 20161BAB216110)+1 种基金China Postdoctoral Science Foundation (No. 2017M612162)Postdoctoral Science Foundation of Jiangxi Province (No. 2017KY02)
文摘Flexoelectricity refers to the mechanical-electro coupling between strain gradient and electric polarization, and conversely, the electro-mechanical coupling between electric field gradient and mechanical stress. This unique effect shows a promising size effect which is usually large as the material dimension is shrunk down. Moreover, it could break the limitation of centrosymmetry, and has been found in numerous kinds of materials which cover insulators, liquid crystals, biological materials, and semiconductors. In this review, we will give a brief report about the recent discoveries in flexoelectricity, focusing on the flexoelectric materials and their applications. The theoretical developments in this field are also addressed. In the end, the perspective of flexoelectricity and some open questions which still remain unsolved are commented upon.
基金supported by the National Natural Science Foundation of China(Nos.11964017,51972157,11864022,and 51662028)the Natural Science Foundation of Jiangxi Province(No.20192ACB21017)。
文摘The resistive switching(RS)mechanism of hybrid organic–inorganic perovskites has not been clearly understood until now.A switchable diode-like RS behavior in MAPbBr3 single crystals using Au(or Pt)symmetric electrodes is reported.Both the high resistance state(HRS)and low resistance state(LRS)are electrode-area dependent and light responsive.We propose an electric-fielddriven inner p–n junction accompanied by a trap-controlled space-charge-limited conduction(SCLC)conduction mechanism to explain this switchable diode-like RS behavior in MAPbBr_(3) single crystals.
