Al-Hakam (may Allah have mercy on him) said to Ibrahim (may Allah have mercy on him): Shall I give my zakah to any one of the eight categories mentioned in the Book of Allah Almighty: "The sadaqat are only for the poor" [Surah al-Tawbah: 60]? He said: Yes.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب قسم الصدقات / 13134