Making Du`a' in a group after the Salah is an act of Bid`ah that has no basis in Shari`ah (Islamic Law), but it is permissible for one to recite Dhikr (Remembrance of Allah) and authentic Du`a' after offering Taslim (salutation of peace ending the Prayer) quietly to oneself, and Allah knows best. (Part No. 2; Page No. 242) May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.