A series of organosilica sols are prepared by the polymeric sol–gel method using 1,2-bis(triethoxysilyl)ethane(BTESE)as the precursor.Particle size distributions of the BTESE-derived sols are systematically investiga...A series of organosilica sols are prepared by the polymeric sol–gel method using 1,2-bis(triethoxysilyl)ethane(BTESE)as the precursor.Particle size distributions of the BTESE-derived sols are systematically investigated by carefully adjusting the synthesis parameters(i.e.,water ratios,acid ratios and solvent ratios)in the sol process.In certain conditions,increasing the water ratio or the acid ratio tends to cause larger sol sizes and bimodal particle size distributions.However,higher solvent ratios lead to smaller sol sizes and unimodal particle size distributions.The organosilica membranes prepared from the optimized sols show excellent H_2 permeances(up to 4.2×10^(-7)mol·m^(-2)·s^(-1)·Pa^(-1))and gas permselectitivies(H_2/CO_2 is 9.5,H_2/N_2 is 50 and H_2/CH_4 is 68).This study offers significant insights into the relationship between the sol synthesis parameters,sol sizes and membrane performance.展开更多
Stress tolerance plays a vital role in ensuring the effectiveness of piezoresistive sensing films used in flexible pressure sensors.However,existing methods for enhancing stress tolerance employ dome-shaped,wrinkle-sh...Stress tolerance plays a vital role in ensuring the effectiveness of piezoresistive sensing films used in flexible pressure sensors.However,existing methods for enhancing stress tolerance employ dome-shaped,wrinkle-shaped,and pyramidal-shaped microstructures in intricate molding and demolding processes,which introduce significant fabrication challenges and limit the sensing performance.To address these shortcomings,this paper presents periodic microslits in a sensing film made of multiwalled carbon nanotubes and polydimethylsiloxane to realize ultrahigh stress tolerance with a theoretical maximum of 2.477 MPa and a sensitivity of 18.092 kPa−1.The periodic microslits permit extensive deformation under high pressure(e.g.,400 kPa)to widen the detection range.Moreover,the periodic microslits also enhance the sensitivity based on simultaneously exhibiting multiple synapses within the sensing interface and between the periodic sensing cells.The proposed solution is verified by experiments using sensors based on the microslit strategy for wind direction detection,robot movement sensing,and human health monitoring.In these experiments,vehicle load detection is achieved for ultrahigh pressure sensing under an ultrahigh pressure of over 400 kPa and a ratio of the contact area to the total area of 32.74%.The results indicate that the proposed microslit strategy can achieve ultrahigh stress tolerance while simplifying the fabrication complexity of preparing microstructure sensing films.展开更多
Electric field(E-field)control of magnetism based on magnetoelectric coupling is one of the promising approaches for manipulating the magnetization with low power consumption.The evolution of magnetic domains under in...Electric field(E-field)control of magnetism based on magnetoelectric coupling is one of the promising approaches for manipulating the magnetization with low power consumption.The evolution of magnetic domains under in-situ E-fields is significant for the practical applications in integrated micro/nano devices.Here,we report the vector analysis of the E-field-driven antiparallel magnetic domain evolution in FeCoSiB/PMN-PT(011)multiferroic heterostructures via in-situ quantitative magneto-optical Kerr microscope.It is demonstrated that the magnetic domains can be switched to both the 0°and 180°easy directions at the same time by E-fields,resulting in antiparallel magnetization distribution in ferromagnetic/ferroelectric heterostructures.This antiparallel magnetic domain evolution is attributed to energy minimization with the uniaxial strains by E-fields which can induce the rotation of domains no more than 90°.Moreover,domains can be driven along only one or both easy axis directions by reasonably selecting the initial magnetic domain distribution.The vector analysis of magnetic domain evolution can provide visual insights into the strain-mediated magnetoelectric effect,and promote the fundamental understanding of electrical regulation of magnetism.展开更多
基金Supported by the National Natural Science Foundation of China(21276123,21490581)the National High Technology Research and Development Program of China(2012AA03A606)+1 种基金the "Summit of the Six Top Talents" Program of Jiangsu Province(2011-XCL-021)the Open Research Fund Program of Collaborative Innovation Center of Membrane Separation and Water Treatment(2016YB01)
文摘A series of organosilica sols are prepared by the polymeric sol–gel method using 1,2-bis(triethoxysilyl)ethane(BTESE)as the precursor.Particle size distributions of the BTESE-derived sols are systematically investigated by carefully adjusting the synthesis parameters(i.e.,water ratios,acid ratios and solvent ratios)in the sol process.In certain conditions,increasing the water ratio or the acid ratio tends to cause larger sol sizes and bimodal particle size distributions.However,higher solvent ratios lead to smaller sol sizes and unimodal particle size distributions.The organosilica membranes prepared from the optimized sols show excellent H_2 permeances(up to 4.2×10^(-7)mol·m^(-2)·s^(-1)·Pa^(-1))and gas permselectitivies(H_2/CO_2 is 9.5,H_2/N_2 is 50 and H_2/CH_4 is 68).This study offers significant insights into the relationship between the sol synthesis parameters,sol sizes and membrane performance.
基金supported by the National Key R&D Program of China(Grant No.2022YFB3204800).
文摘Stress tolerance plays a vital role in ensuring the effectiveness of piezoresistive sensing films used in flexible pressure sensors.However,existing methods for enhancing stress tolerance employ dome-shaped,wrinkle-shaped,and pyramidal-shaped microstructures in intricate molding and demolding processes,which introduce significant fabrication challenges and limit the sensing performance.To address these shortcomings,this paper presents periodic microslits in a sensing film made of multiwalled carbon nanotubes and polydimethylsiloxane to realize ultrahigh stress tolerance with a theoretical maximum of 2.477 MPa and a sensitivity of 18.092 kPa−1.The periodic microslits permit extensive deformation under high pressure(e.g.,400 kPa)to widen the detection range.Moreover,the periodic microslits also enhance the sensitivity based on simultaneously exhibiting multiple synapses within the sensing interface and between the periodic sensing cells.The proposed solution is verified by experiments using sensors based on the microslit strategy for wind direction detection,robot movement sensing,and human health monitoring.In these experiments,vehicle load detection is achieved for ultrahigh pressure sensing under an ultrahigh pressure of over 400 kPa and a ratio of the contact area to the total area of 32.74%.The results indicate that the proposed microslit strategy can achieve ultrahigh stress tolerance while simplifying the fabrication complexity of preparing microstructure sensing films.
基金supported by the National Key R&D Program of China(Grant No.2018YFB0407601)the National Natural Science Foundation of China(Grant Nos.91964109,62071374,and 51802248)+1 种基金the National 111 Project of China(Grant No.B14040)the Fundamental Research Funds for the Central Universities(Grant No.xxj022020008).
文摘Electric field(E-field)control of magnetism based on magnetoelectric coupling is one of the promising approaches for manipulating the magnetization with low power consumption.The evolution of magnetic domains under in-situ E-fields is significant for the practical applications in integrated micro/nano devices.Here,we report the vector analysis of the E-field-driven antiparallel magnetic domain evolution in FeCoSiB/PMN-PT(011)multiferroic heterostructures via in-situ quantitative magneto-optical Kerr microscope.It is demonstrated that the magnetic domains can be switched to both the 0°and 180°easy directions at the same time by E-fields,resulting in antiparallel magnetization distribution in ferromagnetic/ferroelectric heterostructures.This antiparallel magnetic domain evolution is attributed to energy minimization with the uniaxial strains by E-fields which can induce the rotation of domains no more than 90°.Moreover,domains can be driven along only one or both easy axis directions by reasonably selecting the initial magnetic domain distribution.The vector analysis of magnetic domain evolution can provide visual insights into the strain-mediated magnetoelectric effect,and promote the fundamental understanding of electrical regulation of magnetism.
