Assalamu Alaykum wa Rahmatu Allahi wa Barakatuh

Only a government, when it takes charge of collection and distribution, it may decide to invest part. Such a decision cannot be left to the Zakah payer himself/herself. The due amount of Zakah is the right of the poor now, not the right of the poor of tomorrow and if the government takes such a decision, it is because it guarantees the living needs of the poor now. Also charitable organizations which receive Zakah from individual Muslims have no right to invest it, they are only agent of the Zakah payer.

Wa Allahu A’alam