The rapid advancement of flexible electronics creates an urgent demand for high-performance printed electronic materials.MXene-based inks have been widely studied and used for screen-printing electronics,while they us...The rapid advancement of flexible electronics creates an urgent demand for high-performance printed electronic materials.MXene-based inks have been widely studied and used for screen-printing electronics,while they usually suffer from poor screen-printability and inadequate mechanical properties of the printed coatings.Therefore,we incorporate 2,2,6,6-tetramethylpiperidinooxy oxidized cellulose nanofibers into MXene ink to regulate its rheology and enhance printability on both porous A4 paper and compact polyethylene terephthalate substrates.The introduction of cellulose enables precise control over the rheology and microstructure of the resultant MXene coatings.Critically,the strong interfacial hydrogen bonding and physical entanglement between cellulose and MXene contribute to the substantial enhancements of the mechanical properties and structural stability of the resultant composite coatings,where a remarkable 9.04-fold increase of hardness and a 1.74-fold increase of Young’s modulus are achieved.The interfacial binding strength between the coating and substrate is also well enhanced with the anchoring of cellulose.This work thereby presents a promising strategy for the design and fabrication of flexible screen-printed electronics.展开更多
Electromagnetic interference(EMI)and radiation of electronic devices are ubiquitous,which are potentially hazardous to the normal operation of electronic equipment and human health.MXenes are extremely attractive in t...Electromagnetic interference(EMI)and radiation of electronic devices are ubiquitous,which are potentially hazardous to the normal operation of electronic equipment and human health.MXenes are extremely attractive in the preparation of EMI shielding materials due to their excellent metallic conductivity and tunable surface chemistry.Herein,by virtue of the designed nanostructure and regulation of interface interactions,we fabricated flexible Fe_(3)O_(4)@Ti_(3)C_(2)Tx MXene/3,4-dihydroxyphenylacetic acid(DOPAC)-epoxidized natural rubber(ENR)elastomers(FMDE)with 3D segregated interconnected structures.The elaborately designed metalligand coordination crosslinking between Fe_(3)O_(4)nanoparticles and DOPAC ligand molecules provides strong interfacial interactions,resulting in significantly reinforced mechanical properties.Compared with Ti_(3)C_(2)Tx/ENR elastomers,the maximum tensile strength and toughness of FMDE are elevadted by~306%and 475%,respectively.Moreover,the 3D segregated conductive network constructed by Fe_(3)O_(4)@Ti_(3)C_(2)Tx nanoflakes resulted from volume exclusion effect of ENR latex and the introduction of magnetic Fe_(3)O_(4)nanoparticles with enhanced electromagnetic wave absorption greatly improved the EMI shielding performance of FMDE,exhibiting an excellent EMI shielding effectiveness of up to 58 dB in the X band(8.2–12.4 GHz)and stable EMI shielding capability during repeated deformations.This work provides a promising strategy for the design and manufacture of novel flexible EMI shielding materials.展开更多
In this paper,some laws of large numbers are established for random variables that satisfy the Pareto distribution,so that the relevant conclusions in the traditional probability space are extended to the sub-linear e...In this paper,some laws of large numbers are established for random variables that satisfy the Pareto distribution,so that the relevant conclusions in the traditional probability space are extended to the sub-linear expectation space.Based on the Pareto distribution,we obtain the weak law of large numbers and strong law of large numbers of the weighted sum of some independent random variable sequences.展开更多
基金supported by the Tianfu Yongxing Laboratory Organized Research Project Funding(Grant No.2023KJGG12)the State Key Laboratory of Polymer Materials Engineering(Grant No.sklpme2022-3-20)+1 种基金the Joint Project for Talent Innovation Sharing Alliance of Quanzhou(Grant No.2022C001L)the Opening Project of Guangxi Key Laboratory of Calcium Carbonate Resources Comprehensive Utilization(Grant No.HZXYKFKT202306).
文摘The rapid advancement of flexible electronics creates an urgent demand for high-performance printed electronic materials.MXene-based inks have been widely studied and used for screen-printing electronics,while they usually suffer from poor screen-printability and inadequate mechanical properties of the printed coatings.Therefore,we incorporate 2,2,6,6-tetramethylpiperidinooxy oxidized cellulose nanofibers into MXene ink to regulate its rheology and enhance printability on both porous A4 paper and compact polyethylene terephthalate substrates.The introduction of cellulose enables precise control over the rheology and microstructure of the resultant MXene coatings.Critically,the strong interfacial hydrogen bonding and physical entanglement between cellulose and MXene contribute to the substantial enhancements of the mechanical properties and structural stability of the resultant composite coatings,where a remarkable 9.04-fold increase of hardness and a 1.74-fold increase of Young’s modulus are achieved.The interfacial binding strength between the coating and substrate is also well enhanced with the anchoring of cellulose.This work thereby presents a promising strategy for the design and fabrication of flexible screen-printed electronics.
基金supported by the National Natural Science Foundation of China (51861165203)China Postdoctoral Science Foundation (2019M653398)+1 种基金Sichuan Science and Technology Program (2020YJ0261)Shiyanjia Lab (www.shiyanjia.com) for the support of VSM and XRD test
文摘Electromagnetic interference(EMI)and radiation of electronic devices are ubiquitous,which are potentially hazardous to the normal operation of electronic equipment and human health.MXenes are extremely attractive in the preparation of EMI shielding materials due to their excellent metallic conductivity and tunable surface chemistry.Herein,by virtue of the designed nanostructure and regulation of interface interactions,we fabricated flexible Fe_(3)O_(4)@Ti_(3)C_(2)Tx MXene/3,4-dihydroxyphenylacetic acid(DOPAC)-epoxidized natural rubber(ENR)elastomers(FMDE)with 3D segregated interconnected structures.The elaborately designed metalligand coordination crosslinking between Fe_(3)O_(4)nanoparticles and DOPAC ligand molecules provides strong interfacial interactions,resulting in significantly reinforced mechanical properties.Compared with Ti_(3)C_(2)Tx/ENR elastomers,the maximum tensile strength and toughness of FMDE are elevadted by~306%and 475%,respectively.Moreover,the 3D segregated conductive network constructed by Fe_(3)O_(4)@Ti_(3)C_(2)Tx nanoflakes resulted from volume exclusion effect of ENR latex and the introduction of magnetic Fe_(3)O_(4)nanoparticles with enhanced electromagnetic wave absorption greatly improved the EMI shielding performance of FMDE,exhibiting an excellent EMI shielding effectiveness of up to 58 dB in the X band(8.2–12.4 GHz)and stable EMI shielding capability during repeated deformations.This work provides a promising strategy for the design and manufacture of novel flexible EMI shielding materials.
基金AcknowledgmentssThe authors thank the National Natural Science Foundation of China(Grant No.12061028)Guangxi Natural Science Foundation Joint Incubation Project(Grant No.2018GXNSFAA294131)+1 种基金Guangxi Natural Science Foundation(Grant No.2018G XNSFAA281011)Innovation Project of Guangxi Graduate Education(Grant No.YCSW2020175)for their financial support。
文摘In this paper,some laws of large numbers are established for random variables that satisfy the Pareto distribution,so that the relevant conclusions in the traditional probability space are extended to the sub-linear expectation space.Based on the Pareto distribution,we obtain the weak law of large numbers and strong law of large numbers of the weighted sum of some independent random variable sequences.
