Method and device for controlling impurity content in electrolytic hydrogen production and electrolytic hydrogen production method

The invention relates to the technical field of electrolytic hydrogen production, in particular to a method and a device for controlling impurity content in electrolytic hydrogen production and a method for electrolytic hydrogen production. The invention discloses a method for controlling impurity content in electrolytic hydrogen production. The method comprises the following steps: (a) modifying platinum on a cathode diffusion layer; (b) modifying platinum on the anode diffusion layer; and (c) carrying out electrolytic hydrogen production by adopting the cathode diffusion layer and/or the anode diffusion layer obtained in the step (a) and/or the step (b), and respectively obtaining hydrogen and oxygen at the cathode and the anode. According to the method, the volume concentration of oxygen in hydrogen collected by the cathode in electrolytic hydrogen production can be controlled to be lower than 4%, meanwhile, the volume concentration of hydrogen in oxygen collected by the anode is controlled to be lower tha