Over the past few years, the experimental and computational analysis of Ion concentration polarization (ICP) phenomenon has been researched in the nanofluidic device. However the ICP has not been fully defined due to problems of analysis inside the nanochannel including external potential, surface potential for EDL (Electric double layer), ions transport with osmotic flow by external and surface potential of nanofluidic device. These problems of analysis are making difficult to analyze the ICP of nanofluidic device. Hence, we propose the computational simulation of nanochannel using COMSOL Mulitphysics for ICP phenomenon with each effects inside the nanochannel. We analyzed the electric field with boundary conditions of surface potential, surface charge density, and EDL model which is derived from Gouy-Chapman model. Also, each elctroosmotic flows by three electric field are generated respectively. Finally, Ions transports in the nanochannel by each electric field and osmotic flow are analyzed compared to each other computational simulations. As a result, we confirmed that three different electric fields make different osmotic flows and ions transports respectively. This result is meaningful for analysis of ICP phenomenon by electric field composed of EDL model which is from Gouy-Chapman, recent model at surface of nanochannel. ⓒ 2014 DGIST
Table Of Contents
1. INTRODUCTION 1- 1.1 Objectives and Motivations 1-- 1.2 Hypotheses 3-- 1.3 Background Information 5-- 1.3.1 Definition of ICP 5-- 1.3.2 History of ICP 12-- 1.3.3 Applications of nanofluidic device using ICP phenomenon 13-- 2. MATERIALS AND METHODS 18-- 2.1 Chapter Overview 18-- 2.2 Theory 19-- 2.2.1 External potential 19-- 2.2.2 Electro double layer (EDL model) 19-- 2.2.3 Electroosmosis by external and surface potential 22-- 2.2.4 Ion transport by electric field and electroosmotic flow 24-- 2.3 Analysis of ICP phenomenon in the nanofluidic device using COMSOL Multiphysics 25-- 2.3.1 Geometry 25-- 2.3.2 External potential (Electrostatic physics) 27-- 2.3.3 Surface potential using potential boundary condition (Electrostatic physics) 27-- 2.3.4 Surface potential using surface charge density boundary condition (Electrostatic physics) 30-- 2.3.5 Surface potential using EDL model (User made physics) 30-- 2.3.6 Electroosmosis (Laminar flow physics) 33-- 2.3.7 Ion transport through nanochannel (Transport of diluted species physics) 35-- 3. RESULTS AND DISCUSSION 38-- 3.1 Potential in the nanochannel 38-- 3.1.1 External potential 38-- 3.1.2 Surface potential 41-- 3.1.3 Surface charge density 44-- 3.1.4 EDL model 47-- 3.2 Electroosmotic flow in the nanochannel 50-- 3.2.1 Velocity of electroosmotic flow 51-- 3.2.2 Pressure in the nanochannel 56-- 3.3 Ion transport 59-- 3.3.1 Na flux by electrophoresis, diffusion, and convection (electroosmotic effect) 60-- 3.3.2 Cl flux by electrophoresis, diffusion, and convection (electroosmotic effect) 67-- 3.3.3 Na concentration in the nanochannel 74-- 3.3.4 Cl concentration in the nanochannel 84-- 4. CONCLUSION 94-- 4.1 Conclusion 94-- 4.2 Future work 94-- REFERENCES 96
Research Interests
Lithium-ion batteries; Novel Materials for rechargeable batteries; Novel energy conversion;storage systems; Electrochemistry; 리튬이차전지; 이차전지용 신규 전극 및 전해액; 신규 에너지변환 및 저장 시스템; 전기화학