Is it permissible to give Zakaah of gold for Da‘wah (proselytization) activities like purchasing and distributing cassette tapes and booklets?

All perfect praise be to Allaah, the Lord of the worlds. I testify that there is none worthy of worship except Allaah and that Muhammad, sallallaahu ‘alayhi wa sallam, is His slave and Messenger.

What you asked for is impermissible, because Allaah Almighty enumerated eight recipients of Zakah, and it is impermissible to use it for anything else. He, the Exalted, says (what means): {Zakah expenditures are only for the poor and for the needy and for those employed to collect [Zakah] and for bringing hearts together [for Islam] and for freeing captives [or slaves] and for those in debt and for the cause of Allaah and for the [stranded] traveler – an obligation [imposed] by Allaah. And Allaah is Knowing and Wise.} [Quran 9:60]

Thus, the payment of Zakah was restricted to those (eight) and no more. What is mentioned by some scholars; that “in the Cause of Allaah” category implies this activity is not valid, for all categories mentioned in the Quranic Verse are, in fact, included under this meaning. Being so, the division loses its significance.

It seems clear that the right opinion is that of the majority of scholars, i.e. Zakah should be exclusive only to those (eight) categories mentioned in the Quranic Verse.

Allaah Knows best.