The advancement of flexible electronics demands improved components,necessitating heat dissipation membranes(HDMs)to exhibit high thermal conductivity while maintaining structural integrity and performance stability e...The advancement of flexible electronics demands improved components,necessitating heat dissipation membranes(HDMs)to exhibit high thermal conductivity while maintaining structural integrity and performance stability even after extensive deformation.Herein,we have devised a laser-modulated reduction technique for graphene oxide(GO),enabling the fabrication of high-quality,large-scale,lowdefect graphene,which yields high-performance HDMs after orderly deposition.The work underscores the crucial role of the laser wavelength and dispersion liquid's coupling intensity in influencing the morphology and properties of graphene.Optimal coupling effect and energy conversion are realized when a laser of 1064 nm wavelength irradiates a triethylene glycol(TEG)/N,N-Dimethylformamide(DMF)dispersion.This unique synergy generates high transient energy,which facilitates the deprotonation process and ensures a swift,comprehensive GO reduction.In contrast to conventional water-based laser reduction methods,the accelerated reaction magnifies the size of the graphene sheets by mitigating the ablation effect.After membrane construction with an ordered structure,the corresponding membrane exhibits a high thermal conductivity of 1632 W m^(-1)K^(-1),requiring only~1/10 of the total preparation time required by other reported methods.Remarkably,the resulting HDM demonstrates superior resilience against creasing and folding,maintaining excellent smoothness and negligible reduction in thermal conductivity after violent rubbing.The combination of exceptional flexibility and thermal conductivity in HDMs paves the way for long-term practical use in the flexible electronics industry.展开更多
Maintaining low modulus while endowing the wide-range linear stretchability to wearable or implantable devices is crucial for these devices to reduce the mechanical mismatch between the devices and human skin/tissue i...Maintaining low modulus while endowing the wide-range linear stretchability to wearable or implantable devices is crucial for these devices to reduce the mechanical mismatch between the devices and human skin/tissue interfaces.However,improving linear stretchability often results in an increased modulus of stretchable electronic materials,which hinders their conformability in long-term quantifiable monitoring of organs.Herein,we develop a hybrid structure involving interlocking low-modulus porous elastomers(Ecoflex-0030)and MXene-based hydrogels with crosslinking networks of polyvinyl alcohol,sodium alginate,and MXene.This hydrogel–elastomer structure exhibits superior performance compared with previous reports,with a wide linear stretchability strain range from 0 to 1000%and maintaining a low modulus of 6.4 kPa.Moreover,the hydrogel–elastomer hybrids can be utilized as highly sensitive strain sensors with remarkable characteristics,including high sensitivity(gauge factor~3.52),a linear correlation between the resistance and strain(0–200%),rapid response(0.18 s)and recovery times(0.21 s),and excellent electrical reproducibility(1000 loading–unloading cycles).Those electrical and mechanical properties allow the sensor to act as a suitable quantifiable equipment in organ monitoring,human activities detecting,and human–machine interactions.展开更多
基金supported by the National Science Foundation of Jiangsu Province(BK20210861)the National Natural Science Foundation of China(62101374)the open research fund of Key Laboratory of MEMS of Ministry of Education,Southeast University。
文摘The advancement of flexible electronics demands improved components,necessitating heat dissipation membranes(HDMs)to exhibit high thermal conductivity while maintaining structural integrity and performance stability even after extensive deformation.Herein,we have devised a laser-modulated reduction technique for graphene oxide(GO),enabling the fabrication of high-quality,large-scale,lowdefect graphene,which yields high-performance HDMs after orderly deposition.The work underscores the crucial role of the laser wavelength and dispersion liquid's coupling intensity in influencing the morphology and properties of graphene.Optimal coupling effect and energy conversion are realized when a laser of 1064 nm wavelength irradiates a triethylene glycol(TEG)/N,N-Dimethylformamide(DMF)dispersion.This unique synergy generates high transient energy,which facilitates the deprotonation process and ensures a swift,comprehensive GO reduction.In contrast to conventional water-based laser reduction methods,the accelerated reaction magnifies the size of the graphene sheets by mitigating the ablation effect.After membrane construction with an ordered structure,the corresponding membrane exhibits a high thermal conductivity of 1632 W m^(-1)K^(-1),requiring only~1/10 of the total preparation time required by other reported methods.Remarkably,the resulting HDM demonstrates superior resilience against creasing and folding,maintaining excellent smoothness and negligible reduction in thermal conductivity after violent rubbing.The combination of exceptional flexibility and thermal conductivity in HDMs paves the way for long-term practical use in the flexible electronics industry.
基金supported by the National Natural Science Foundation of China(62001066,62104022,and 61971074)the Natural Science Foundation of Chongqing(2022NSCQ-MSX2366)+11 种基金the Fundamental Research Funds for the Central Universities(2020CDJ-LHZZ069 and 2020CDJYGGD004)the open research fund of Key Laboratory of MEMS of Ministry of Education,Southeast Universitythe Science and Technology Research Program of Chongqing Municipal Education Commission(kjzd-k202000105)the Start-up Foundation of Nanjing Vocational University of Industry Technology(YK21-03-02201012321DXS79HK2351-10:205050623HK097)the Natural Science Foundation of Jiangsu Province(BK20160702)the High-level Training Project for Professional-leader Teachers of Higher Vocational Colleges in Jiangsu Province(2023TDFX007)the Ministry of Science and Technology of China(2017YFA0204800)the National Natural Science Foundation of China(51420105003,11525415,11327901,61274114,61601116,11674052,and 11204034)the Fundamental Research Funds for the Central Universities(2242017K40066,2242017K40067,2242016K41039,2242020K40023,and 2242019R10)funded by the Administration Office of Jiangsu Talent resources。
文摘Maintaining low modulus while endowing the wide-range linear stretchability to wearable or implantable devices is crucial for these devices to reduce the mechanical mismatch between the devices and human skin/tissue interfaces.However,improving linear stretchability often results in an increased modulus of stretchable electronic materials,which hinders their conformability in long-term quantifiable monitoring of organs.Herein,we develop a hybrid structure involving interlocking low-modulus porous elastomers(Ecoflex-0030)and MXene-based hydrogels with crosslinking networks of polyvinyl alcohol,sodium alginate,and MXene.This hydrogel–elastomer structure exhibits superior performance compared with previous reports,with a wide linear stretchability strain range from 0 to 1000%and maintaining a low modulus of 6.4 kPa.Moreover,the hydrogel–elastomer hybrids can be utilized as highly sensitive strain sensors with remarkable characteristics,including high sensitivity(gauge factor~3.52),a linear correlation between the resistance and strain(0–200%),rapid response(0.18 s)and recovery times(0.21 s),and excellent electrical reproducibility(1000 loading–unloading cycles).Those electrical and mechanical properties allow the sensor to act as a suitable quantifiable equipment in organ monitoring,human activities detecting,and human–machine interactions.
