Transfer printing based on switchable adhesive that heterogeneously integrates materials is essential to develop novel electronic systems,such as flexible electronics and micro LED displays.Here,we report a robust des...Transfer printing based on switchable adhesive that heterogeneously integrates materials is essential to develop novel electronic systems,such as flexible electronics and micro LED displays.Here,we report a robust design of a thermal actuated switchable dry adhesive,which features a stiff sphere embedded in a thermally responsive shape memory polymer(SMP)substrate and encapsulated by an elastomeric membrane.This construct bypasses the unfavorable micro-and nano-fabrication processes and yields an adhesion switchability of over1000 by combining the peel-rate dependent effect of the elastomeric membrane and the thermal actuation of the sub-surface embedded stiff sphere.Experimental and numerical studies reveal the underlying thermal actuated mechanism and provide insights into the design and operation of the switchable adhesive.Demonstrations of this concept in stamps for transfer printing of fragile objects,such as silicon wafers,silicon chips,and inorganic micro-LED chips,onto challenging non-adhesive surfaces illustrate its potential in heterogeneous material integration applications,such as flexible electronics manufacturing and deterministic assembly.展开更多
Recently, there has been significant research interest in higher-order topological states within artificial lattices, primarily due to their potential for manipulating waves. In this study, we focus on a three-dimensi...Recently, there has been significant research interest in higher-order topological states within artificial lattices, primarily due to their potential for manipulating waves. In this study, we focus on a three-dimensional hexagonal bilayer acoustic crystal with rotation, layer, and translation degrees of freedom. By systematically reducing the crystal symmetries, we realize a full hierarchical structure of the higher-order topological states. This hierarchical progression begins with the valley-induced twodimensional surface state, followed by the one-dimensional hinge state that arises from the topological obstruction, and ultimately culminating in the zero-dimensional corner state resulting from the edge polarization mechanism. Through finite element simulations and numerical calculations of topological invariants, we confirm the topological origins of all these hierarchical states. Moreover, we successfully verified the full hierarchical topology by directly probing the acoustic field within a finitesized three-dimensional sample. This study offers novel perspectives on the fundamental research pertaining to wave modulation and the intelligent control of sound fields.展开更多
Wearable electronics have continued to attract the attention of researchers and clinicians due to their great potential in medical applications.During their operations,the undesired heating may cause thermal discomfor...Wearable electronics have continued to attract the attention of researchers and clinicians due to their great potential in medical applications.During their operations,the undesired heating may cause thermal discomfort or damage to skin.Seeking materials and structures for advanced thermal protection has become an urgent issue.Here,we report a soft,stretchable thermal protective substrate for wearable electronics with remarkable thermal insulating performance,mechanical compliance and stretchability.The thermal protective substrate features a composite design of the widely used polymeric material polydimethylsiloxane with embedded heat absorbing microspheres,consisting of phase change materials encapsulated inside the resin shell.Experimental and numerical studies show that the thermal protective substrate could be subjected to complex deformations over 150% and could reduce the peak skin temperature increase by 82% or higher under optimizations.In vivo demonstration of this concept on the mouse skin illustrates its unusual thermal protection capability for wearable thermal management.展开更多
基金financial support from the National Natural Science Foundation of China(Grant Nos.11872331 and U20A6001)the Zhejiang University K P Chao’s High Technology Development Foundation。
文摘Transfer printing based on switchable adhesive that heterogeneously integrates materials is essential to develop novel electronic systems,such as flexible electronics and micro LED displays.Here,we report a robust design of a thermal actuated switchable dry adhesive,which features a stiff sphere embedded in a thermally responsive shape memory polymer(SMP)substrate and encapsulated by an elastomeric membrane.This construct bypasses the unfavorable micro-and nano-fabrication processes and yields an adhesion switchability of over1000 by combining the peel-rate dependent effect of the elastomeric membrane and the thermal actuation of the sub-surface embedded stiff sphere.Experimental and numerical studies reveal the underlying thermal actuated mechanism and provide insights into the design and operation of the switchable adhesive.Demonstrations of this concept in stamps for transfer printing of fragile objects,such as silicon wafers,silicon chips,and inorganic micro-LED chips,onto challenging non-adhesive surfaces illustrate its potential in heterogeneous material integration applications,such as flexible electronics manufacturing and deterministic assembly.
基金This work was supported by the Key-Area Research and Development Program of Guangdong Province(2020B010190002)the National Natural Science Foundation of China(11890701,11874383,12104480,11974005,and 12222405)+1 种基金the National Key R&D Program of China(2018YFA0305800)the IACAS Frontier Exploration Project(QYTS202110).
基金supported by the Key-Area Research and Development Program of Guangdong Province(Grant No.2020B010190002)the National Natural Science Foundation of China(Grant No.12104480)the IACAS Frontier Exploration Project(Grant No.QYTS202110)。
文摘Recently, there has been significant research interest in higher-order topological states within artificial lattices, primarily due to their potential for manipulating waves. In this study, we focus on a three-dimensional hexagonal bilayer acoustic crystal with rotation, layer, and translation degrees of freedom. By systematically reducing the crystal symmetries, we realize a full hierarchical structure of the higher-order topological states. This hierarchical progression begins with the valley-induced twodimensional surface state, followed by the one-dimensional hinge state that arises from the topological obstruction, and ultimately culminating in the zero-dimensional corner state resulting from the edge polarization mechanism. Through finite element simulations and numerical calculations of topological invariants, we confirm the topological origins of all these hierarchical states. Moreover, we successfully verified the full hierarchical topology by directly probing the acoustic field within a finitesized three-dimensional sample. This study offers novel perspectives on the fundamental research pertaining to wave modulation and the intelligent control of sound fields.
基金support of the National Natural Science Foundation of China (Grant Nos,U20A6001 and 11872331)National Key Research and Development Program of China (Grant No,2019YFE0117400)Zhejiang University K.P.Chao’s High Technology Development Foundation.
文摘Wearable electronics have continued to attract the attention of researchers and clinicians due to their great potential in medical applications.During their operations,the undesired heating may cause thermal discomfort or damage to skin.Seeking materials and structures for advanced thermal protection has become an urgent issue.Here,we report a soft,stretchable thermal protective substrate for wearable electronics with remarkable thermal insulating performance,mechanical compliance and stretchability.The thermal protective substrate features a composite design of the widely used polymeric material polydimethylsiloxane with embedded heat absorbing microspheres,consisting of phase change materials encapsulated inside the resin shell.Experimental and numerical studies show that the thermal protective substrate could be subjected to complex deformations over 150% and could reduce the peak skin temperature increase by 82% or higher under optimizations.In vivo demonstration of this concept on the mouse skin illustrates its unusual thermal protection capability for wearable thermal management.
