Abu Hazim reported,

People disagreed about what was used to treat the wound of the Messenger of Allah ﷺ on the day of Uhud, so they asked Sahl bin Saad al-Saidi, who was among the last of the companions of the Prophet ﷺ remaining in Madinah.He said, "No one alive knows more about this than I do. Fatimah, peace be upon her, was washing the blood from his face while Ali brought water on his shield. Then a piece of straw mat was taken and burned, and his wound was packed with its ashes."

Bukhari 5248

Sahih

حدثنا قتيبة بن سعيد حدثنا سفيان

عن أبي حازم قال

اختلف الناس بأي شيء دووي جرح رسول الله ﷺ يوم أحد فسألوا سهل بن سعد الساعدي وكان من آخر من بقي من أصحاب النبي ﷺ بالمدينة فقال وما بقي من الناس أحد أعلم به مني كانت فاطمة عليها السلام تغسل الدم عن وجهه وعلي يأتي بالماء على ترسه فأخذ حصير فحرق فحشي به جرحه

البخاري 5248صحيح
Contents
Reference
Commentary
Ayat
Collection
Sahih Bukhari
Book
Marriage
Chapter
And let them not reveal their adornment except to their husbands" up to His saying, "who have not yet attained awareness of the private aspects of women
Numbering
Darussalam 5248
Bukhari 5248