Developing wireless nanodevices and nanosystems is of critical importance for sensing, medical science, environmental/infrastructure monitoring, defense technology and even personal electronics. It is highly desirable...Developing wireless nanodevices and nanosystems is of critical importance for sensing, medical science, environmental/infrastructure monitoring, defense technology and even personal electronics. It is highly desirable for wireless devices to be self-powered without using battery, without which most of the sensor network may be impossible. The pie- zoelectric nanogenerators have the potential to serve as self-sufficient power sources for micro/nano systems. For wurtzite structures that have non-central symmetry, such as ZnO, GaN and InN, a piezoelectric potential （piezopotential） is created in the crystal by applying a strain. The nanogenerator is invented by using the piezopotential as the driving force for electrons to flow in respond to a dynamic straining of piezoelectric nanowires. A gentle straining can produce an output voltage of up to 20 - 50 V from an integrated nanogenerator. Furthermore, piezopotential in the wurtzite structure can serve as gate voltage that can effectively tune/control the charge transport across an interface/junction; electronics fabricated based on such a mechanism is coined as piezotronics, with applications in force/pressure triggercd/controlled electronic devices, sensors, logic units and memory. By using the piezotronic effect, it is showed that the optoelectronic devices fabricated using wurtzite materials can have superior performance as solar cell, photon detector and light emitting diode. Piezotronie is likely to serve as ＂mechanosensation＂ for directly interfacing biomechanieal action with silicon based technology and active flexible electronics. The paper gives a brief review about the basis of nanogenertors and piezotronics and their potential applications in smart MEMS （micro-electro-mechanical systems）.展开更多
The field of stretchable electronics mainly includes electronic products conformal with tissues,being integrated into skin or clothing.Since these products need to work during deformation,their requirements for materi...The field of stretchable electronics mainly includes electronic products conformal with tissues,being integrated into skin or clothing.Since these products need to work during deformation,their requirements for materials focus on stretchability and conductivity.Liquid metals are excellent materials with these properties.However,liquid metals have extremely high surface tension at room temperature,which will spontaneously form a spherical shape and are difficult to form the shape required by stretchable devices,which is the biggest obstacle to their development in this emerging field.Therefore,the emphasis is placed on the principle of overcoming the high surface tension in this review,and various methods of using liquid metals to fabricate stretchable electronic devices based on these principles have been linked.Liquid metals show promise in the convenience of sensing,energy harvesting,etc.The existing challenges and opportunities are also discussed here.展开更多
文摘Developing wireless nanodevices and nanosystems is of critical importance for sensing, medical science, environmental/infrastructure monitoring, defense technology and even personal electronics. It is highly desirable for wireless devices to be self-powered without using battery, without which most of the sensor network may be impossible. The pie- zoelectric nanogenerators have the potential to serve as self-sufficient power sources for micro/nano systems. For wurtzite structures that have non-central symmetry, such as ZnO, GaN and InN, a piezoelectric potential （piezopotential） is created in the crystal by applying a strain. The nanogenerator is invented by using the piezopotential as the driving force for electrons to flow in respond to a dynamic straining of piezoelectric nanowires. A gentle straining can produce an output voltage of up to 20 - 50 V from an integrated nanogenerator. Furthermore, piezopotential in the wurtzite structure can serve as gate voltage that can effectively tune/control the charge transport across an interface/junction; electronics fabricated based on such a mechanism is coined as piezotronics, with applications in force/pressure triggercd/controlled electronic devices, sensors, logic units and memory. By using the piezotronic effect, it is showed that the optoelectronic devices fabricated using wurtzite materials can have superior performance as solar cell, photon detector and light emitting diode. Piezotronie is likely to serve as ＂mechanosensation＂ for directly interfacing biomechanieal action with silicon based technology and active flexible electronics. The paper gives a brief review about the basis of nanogenertors and piezotronics and their potential applications in smart MEMS （micro-electro-mechanical systems）.
基金supported by the National Natural Science Foundation of China(52173237 and 51903068)the Natural Science Foundation of Heilongjiang Province,China(YQ2020E001)。
文摘The field of stretchable electronics mainly includes electronic products conformal with tissues,being integrated into skin or clothing.Since these products need to work during deformation,their requirements for materials focus on stretchability and conductivity.Liquid metals are excellent materials with these properties.However,liquid metals have extremely high surface tension at room temperature,which will spontaneously form a spherical shape and are difficult to form the shape required by stretchable devices,which is the biggest obstacle to their development in this emerging field.Therefore,the emphasis is placed on the principle of overcoming the high surface tension in this review,and various methods of using liquid metals to fabricate stretchable electronic devices based on these principles have been linked.Liquid metals show promise in the convenience of sensing,energy harvesting,etc.The existing challenges and opportunities are also discussed here.
