This dua is recited in namaz, which is in Surah 2nd verse 201 of the Quran.
رَبَّنَآ اٰتِنَا فِي الدُّنْيَا حَسَنَةً وَّفِي الْاٰخِرَةِ حَسَـنَةً وَّقِنَا عَذَابَ النَّارِ
Rabbana Dua Transliteration
Rabbanaaa Aatinaa Fiddunyaa H’asanataw Wa Fil Aakhirati H’asanataw Wa Qinaa A’d’aaban Naar
English Translation
Our Lord! Give us in this world that which is good and in the Hereafter that which is good, and save us from the torment of the Fire!
Surah Al-Baqarah – 2:201
See Also: Dua-e-Qunoot in Arabic, English