Scalable Membraneless Direct Liquid Fuel Cells Based on a Catalyst-Selective Strategy

This perspective presents a membraneless direct liquid fuel cell(DLFC)concept based on a catalyst-selective strategy.The membraneless DLFCs are operated at low temperatures by employing a non-precious cathode catalyst with a high catalytic selectivity.The uniqueness is that the inexpensive cathode catalyst only catalyzes the oxygen reduction reaction but does not catalyze the oxidation reaction of a specific fuel.Therefore,during the operation of DLFCs,the liquid fuel can enter the cathode freely without any concern of fuel crossover.This catalyst-selective approach tactfully avoids the use of high-cost or technically unviable ion-exchange polymer membranes in DLFCs.The catalyst-selective operating principle also overcomes the scalability issue of the traditional laminar-flow membraneless DLFCs.Through a proper management of the anode and cathode catalysts in the cell,a variety of inexpensive,renewable alcohols,and small-molecule organics can be employed as anode fuels.This innovative approach of membraneless alkaline DLFCs offers a great opportunity for the development of inexpensive energy-generation systems for both mobile and stationary applications.In addition to summarizing the principle and the research progress of the unique membraneless DLFC platform,the challenges and future research directions are presented.