Preparation And Study Of Nanochannels Based On Magnetic Response Materials

In recent years,with the rapid development of micro-nano preparation technology,nanofluids have attracted extensive attention in various fields.Due to the unique effect of nanometer size,nanofluids have more excellent properties,such as ion selectivity,ion enrichment effect,and ultra-high detection sensitivity.Although the current nanofluidic research has made great progress and many responsive devices emerge in an endless stream,but magnetic field regulation has rarely been reported.At the same time,the current smart micro-nano devices are still limited to complex chemical modifications,low operational stability etc.This greatly limits its application prospects in large-area preparation.However,biological nanochannels on cell membranes play an important role in cell biology and life activities,exhibiting excellent ion selectivity and responsive characteristics.Inspired by these intelligent biological nanochannels,this paper fabricated a magnetically responsive solid-state nanochannels with excellent performance.We have realized magnetic response gating research,magnetic response liquid gating with utral gatingratio and magnetic response energy conversion.The main content works of this paper are as follows:1.Through study of the navigation mechanism of home pigeons,we found that the navigation process is the magnetic rod stretching of the cell membrane under different geomagnetic which causing the different ion transport behavior of the protein pores.Inspired by this mechanism,we introduce a magnetic elastomer into the surface of the polymer film with a chemically etched channel(conical channel).By applying magnetic fields of different intensities,we can achieve the stretching of the pores and realize the controllable rectification ratio.Further study of the direction of magnetic field application(large pore side VS small pore side),we found that the different degrees of rectification effect was caused by the different deformations of the elastmer(stretching and compression).This research provides a new idea for the nanofluidic field and also adds new members to the intelligentlly responsive nanochannel.2.Porous alumina films were prepared by electrochemical etching,and then were modified by the silane coupling agents with different end groups.Nanochannels with different wettability and adhesion were prepared.On this basis,ferrofluid was introduced into the nanofluidic system.Through the synergistic effect of magnetic field and surface tension,we realized the controllable ion transport performance on the superhydrophilic nanochannel.Further research found that the nano-gating can achieve multiple consecutive stable reversible cycles due to the low oil adhesion of superhydrophilic surface.Through theoretical simulation and energy calculation,we further verified the switching mechanism of the system.And we further extended the system to controllable ion diffusion and galvanic cell fields to achieve a stable switching process.This work provides valuable reference for the application of super-hydrophilic in the nanofluidic system.3.Inspired by the energy conversion systems in biological system(eg,electrohydraulic discharge,ATP synthesis,retina,purple film,etc.)and magnetic field navigation of home pigeons,we designed and developed a bionic single nanochannel energy conversion system.From the two aspects of the response mechanism and energy conversion,we construct a nano-electrical device with magnetic induction based on the ferrofluid as an electrolyte combined with ion selective nanochannel.The external magnetic field can regulate the position of the ferrofluid to realize the switching effect of the entire circuit.And we studied the effects of magnetic electrolyte concentration,pH,membrane pore size,etc.on power generation behavior,and achieved ultra-high power generation.Further theoretical analysis found that the high power generation is due to the large difference in size of the positive and negative charges of the electrolyte,charge quantity and mobility.This design opens up a new path for the development of concentration power generation system.