As a result of frequent food waste and environmental pollution,there has been an increasing demand for the development of packaging materials that intrinsically inhibit and reduce likelihood of non-Newtonian liquids a...As a result of frequent food waste and environmental pollution,there has been an increasing demand for the development of packaging materials that intrinsically inhibit and reduce likelihood of non-Newtonian liquids adherence.In this work,inspired from ciliary structures on the leg of water strider,the hierarchical conical array was formed by magnetic field control and laser etching without any mask.Due to the tapered geometry of the cones and the multiscale surface roughness of the array,the droplets would bounce many times after impacting with the superhydrophobic surface(SHS)and roll off.By changing the spaces and apex angles of conical microcolumns the SHS has controlled adhesion,superior self-cleaning property and droplets bounce performance for a variety of non-Newtonian viscous liquids.After suffering from various types of damage including repeated tape tearing,finger touch and folding test,the SHS still maintained excellent superhydrophobic property,which may have potential application as all kinds of packaging interface materials.We demonstrate that the excellent droplets bounce behavior of the hierarchical array enables the efficient and robust prevention of food liquids adhesion.展开更多
Magnetic liquid metal droplets(MLMDs)have been proven to be very important in many fields such as flexible electronics and soft robotics.Usually,soft magnetic particles such as nickel(Ni)and iron(Fe)are mixed or suspe...Magnetic liquid metal droplets(MLMDs)have been proven to be very important in many fields such as flexible electronics and soft robotics.Usually,soft magnetic particles such as nickel(Ni)and iron(Fe)are mixed or suspended into the liquid metal to obtain soft MLMDs(S-LMDs),which can be easily manipulated under the magnetic field due to the favorable deformability and flexibility.In addition,hard magnetic particles such as neodymium iron boron(Nd Fe B)with a high residual magnetization can also be dispersed into the liquid metal and the hard MLMDs(H-LMDs)become more compact due to the interaction between internal particles induced by remanence.This work reports a kind of H-LMDs with high surface tension,high flexibility and mechanical robustness,whose electrical conductivity and strength are better than the S-LMDs.Under the magnetic field,the H-LMDs have a faster response time(0.58 s)and a larger actuating velocity(4.45 cm/s)than the S-LMDs.Moreover,the H-LMDs show excellent magnetic controllability,good elasticity and favorable mobility,as demonstrated by magnetically actuated locomotion,bounce tests and rolling angle measurements.Finally,the droplets can be further applied in wheeldriven motors and micro-valve switches,which demonstrates their high application potential in robotic manipulation and microfluidic devices.展开更多
基金National Natural Science Foundation of China(Nos.52005222 and 51805048)China Postdoctoral Science Foundation(2020M671372)Natural Science Foundation of Jiangsu Province(BK20181036).
文摘As a result of frequent food waste and environmental pollution,there has been an increasing demand for the development of packaging materials that intrinsically inhibit and reduce likelihood of non-Newtonian liquids adherence.In this work,inspired from ciliary structures on the leg of water strider,the hierarchical conical array was formed by magnetic field control and laser etching without any mask.Due to the tapered geometry of the cones and the multiscale surface roughness of the array,the droplets would bounce many times after impacting with the superhydrophobic surface(SHS)and roll off.By changing the spaces and apex angles of conical microcolumns the SHS has controlled adhesion,superior self-cleaning property and droplets bounce performance for a variety of non-Newtonian viscous liquids.After suffering from various types of damage including repeated tape tearing,finger touch and folding test,the SHS still maintained excellent superhydrophobic property,which may have potential application as all kinds of packaging interface materials.We demonstrate that the excellent droplets bounce behavior of the hierarchical array enables the efficient and robust prevention of food liquids adhesion.
基金Financial support from the National Natural Science Foundation of China(Grant Nos.11822209,12072338,11772320)the Fundamental Research Funds for the Central Universities(WK2480000007)+2 种基金Joint Fund of USTC-National Synchrotron Radiation Laboratory(KY2090000055)the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB22040502)Thanks to the instrumentation support from engineering practice center of USTC。
文摘Magnetic liquid metal droplets(MLMDs)have been proven to be very important in many fields such as flexible electronics and soft robotics.Usually,soft magnetic particles such as nickel(Ni)and iron(Fe)are mixed or suspended into the liquid metal to obtain soft MLMDs(S-LMDs),which can be easily manipulated under the magnetic field due to the favorable deformability and flexibility.In addition,hard magnetic particles such as neodymium iron boron(Nd Fe B)with a high residual magnetization can also be dispersed into the liquid metal and the hard MLMDs(H-LMDs)become more compact due to the interaction between internal particles induced by remanence.This work reports a kind of H-LMDs with high surface tension,high flexibility and mechanical robustness,whose electrical conductivity and strength are better than the S-LMDs.Under the magnetic field,the H-LMDs have a faster response time(0.58 s)and a larger actuating velocity(4.45 cm/s)than the S-LMDs.Moreover,the H-LMDs show excellent magnetic controllability,good elasticity and favorable mobility,as demonstrated by magnetically actuated locomotion,bounce tests and rolling angle measurements.Finally,the droplets can be further applied in wheeldriven motors and micro-valve switches,which demonstrates their high application potential in robotic manipulation and microfluidic devices.