Al Salam Alaykom brother, and thanks for this nice question Allah bless. I quote you the answer you desire In Sha Allah:
Several du’aa’s have been reported that the Prophet (peace and blessings of Allaah be upon him) said in his sujood, none of which contain blessings upon the Prophet (peace and blessings of Allaah be upon him). These du’aa’s include the following:
It was narrated that ‘Aa’ishah (may Allaah be pleased with her) said: “The Prophet (peace and blessings of Allaah be upon him) often used to say in his sujood and rukoo’: ‘Subhaanaka Allaahumma Rabbanaa wa bi hamdika, Allaahumma ighfir li (Glory and praise be to You, O Allaah our Lord; O Allaah, forgive me).’” (Narrated by al-Bukhaari, 874; Muslim, 484).
And it was narrated that ‘Aa’ishah said: “one night I noticed that the Messenger of Allaah (peace and blessings of Allaah be upon him) was not in his bed, so I reached out looking for him, and my hand touched the soles of his feet; he was in his prayer place and his feet were upright (i.e., he was prostrating), and he was saying, ‘Allaahumma a’oodhu bi ridaaka min sakhatika wa bi mu’aafaatika min ‘aqoobatika wa a’oodhi bika minka laa uhsi thanaa’an ‘alayka anta kamaa athnayta ‘ala nafsika (O Allaah, I seek refuge in Your good pleasure from Your wrath, and I seek refuge in Your pardon from Your punishment. I seek refuge in You from You. I cannot enumerate Your praise, You are as You have praised Yourself).’”
(Narrated by Muslim, 486)
So the ones are authentic above. May Allah bless you.