Quite difficult thing, it is a very aggressive media. Although is a XIX technique you can use Mercury amalgamated in Copper Plates...Zinc will make an amalgam, that youy can revert inversing polarity and obtain either Zn Hydroxide or Zn metal, depending on the electrolyte. Mercury is a magnificent, albeit difficult, material to work with...

You are refering to cathode,,,aren´t you? I was asking for alternative anode materials. Thank you anyway.