From Sahih Bukhari (Hadith 3271):
Narrated Ibn `Abbas:The Prophet (ﷺ) said, "If anyone of you, when having sexual relation with his wife, say: 'In the name of Allah. O Allah! Protect us from Satan and prevent Satan from approaching our offspring you are going to give us,' and if he begets a child (as a result of that relation) Satan will not harm it
Reference: Bukhari 3271