Strategic comparison of membrane-assisted and membrane-less water electrolyzers and their potential application in direct seawater splitting(DSS)  

作　　者：Abdul Malek Xu Lu Paul R.Shearing Dan J.L.Brett Guanjie He 

机构地区：[1]Clean Combustion Research Center(CCRC),Physical Science and Engineering Division(PSE),King Abdullah University of Science and Technology(KAUST),Thuwal 23955-6900,Kingdom of Saudi Arabia [2]KAUST Solar Center(KSC),Physical Science and Engineering Division(PSE),King Abdullah University of Science and Technology(KAUST),Thuwal 23955-6900,Kingdom of Saudi Arabia [3]School of Engineering and Materials Science,Queen Mary University of London,Mile End Road,London E14NS,UK [4]Department of Chemical Engineering,University College London(UCL),Gower St,London WC1E 6BT,United Kingdom

出　　处：《Green Energy & Environment》2023年第4期989-1005,共17页绿色能源与环境（英文版）

基　　金：King Abdullah University of Science and Technology for funding through the funding grant (BAS/1/1413-01-01);the Engineering and Physical Sciences Research Council (EPSRC,EP/V027433/1);the Royal Society (RGSR1211080;IESR2212115)。

摘　　要：Electrocatalytic splitting of water by means of renewable energy as the electricity supply is one of the most promising methods for storing green renewable energy as hydrogen. Although two-thirds of the earth’s surface is covered with water, there is inadequacy of freshwater in most parts of the world. Hence, splitting seawater instead of freshwater could be a truly sustainable alternative. However, direct seawater splitting faces challenges because of the complex composition of seawater. The composition, and hence, the local chemistry of seawater may vary depending on its origin, and in most cases, tracking of the side reactions and standardizing and customizing the catalytic process will be an extra challenge. The corrosion of catalysts and competitive side reactions due to the presence of various inorganic and organic pollutants create challenges for developing stable electro-catalysts. Hence, seawater splitting generally involves a two-step process, i.e., purification of seawater using reverse osmosis and then subsequent fresh water splitting. However, this demands two separate chambers and larger space, and increases complexity of the reactor design. Recently, there have been efforts to directly split seawater without the reverse osmosis step. Herein, we represent the most recent innovative approaches to avoid the two-step process, and compare the potential application of membrane-assisted and membrane-less electrolyzers in direct seawater splitting(DSS). We particularly discuss the device engineering, and propose a novel electrolyzer design strategies for concentration gradient based membrane-less microfluidic electrolyzer.

关 键 词：Electrocatalytic seawater splitting Direct seawater splitting Osmosis Concentration cells Membrane-less electrolyzer Microfluidic electrolyzer 

分 类 号：P747[天文地球—海洋科学]