Study Of Salinity Difference Energy Conversion Based On Nuclear Track Membrane Nanocomposites

With the process of industrialization,the massive use of fossil energy has brought serious environmental pollution problems.The search for clean,pollution-free alternative energy has become a key issue for the sustainable development of human society.The difference in salt concentration in the concentration gradient of the river estuary can be considered as a potential clean and pollution-free energy source.In this thesis,the nuclear pore film nanocomposites were prepared by heavy energy ion track etching,and the mechanism of energy conversion in the porous system was studied.Firstly,we studied the influencing factors of the energy conversion of different electrolytes in a tandem system.We found that the electrical energy conversion capability of the system is closely related to the type of electrolyte,the concentration gradient across the nanopore,the geometry of the nanopore,and the surface charge density.By choosing suitable electrolytes and nanopores,we can achieve greater energy conversion efficiency.Secondly,taking the NaCl solution widely found in seawater as an example,we further studied the relationship between energy conversion and surface charge density of ion-selective membranes.The results show that the energy conversion is related to the surface charge density of the anion and cation membranes.In the case where the total surface charge density is equal,the electric power is the highest when the surface charge density of anion selective membrane is slightly lower than the cation selective membrane.Finally,we studied the dependence of pore density on energy conversion of nanofluids by thermodynamic analysis and numerical simulation.The traditional view is that electrical power increases with the increasing of pore density.However,we found that the power density appears to be non-linear as the pore density increases.Too high pore density reduces ion selectivity and produces concentration polarization at the low concentration side of the nanopore,ultimately impairing the ability of the electrical energy to convert.The optimal hole density exists to maximize the power density of the salt difference power generation system.This work has conducted an in-depth study of the nanofluid system energy conversion and revealed the physical mechanisms that affect the salinity difference power generation in the nanofluidic system,providing a certain guiding significance for the design of a more efficient nanofluidic system.