Research Progress in Technology to Reduce the Transfer Overvoltage during Water Electrolysis
At present,due to the existence of reaction overvoltage and mass transfer overvoltage in water electrolysis technology,the electrolytic efficiency is low.Most researchers focus on the development of catalysts with higher activity to reduce the reaction overvoltage and improve the electrolytic efficiency.In this paper,we summarize the technology of reducing the mass transfer overvoltage in the electrolytic process from the point of view of gas-liquid flow and mass transfer that occurs in the electrolyte,including setting magnetic field,ultrasonic field and supergravity force field,and analyze their strengthening principle.In addition,the methods to reduce the mass transfer overvoltage by optimizing the operating conditions of the electrolytic process including changing the operating temperature,operating pressure and power supply mode of electrolytic cell are also summarized.Magnetic field changes can accelerate the ion migration.The ultrasonic field can effectively reduce the average size and separation time of the dispersed bubbles in the electrolyte,and strengthen the mass transfer.The extra gravity provides a stronger force for mass transfer and makes it easier for bubbles to escape from the electrode surface.The increase of temperature can speed up the reaction rate and reduce the power consumption,but it needs to increase the operating pressure to adjust the saturation of electrolyte,which may lead to the increase of equipment cost.Pulse power supply has lower energy consumption than traditional stable DC power supply.
Water electrolysisMass transfer overvoltageExternal force field intensificationOperating condition optimization
NETL
NSTL
万方数据
维普
