Weak
Jami' at-Tirmidhi 3700
"I witnessed the Prophet (ﷺ) while he was exhorting support for the 'army of distress.' 'Uthman bin 'Affan stood and said: 'O Messenger of Allah! I will take the responsibility of one-hundred camels, including their saddles and water-skins, in the path of Allah.' Then he [(ﷺ) again] urged support…
" مَا عَلَى عُثْمَانَ مَا عَمِلَ بَعْدَ هَذِهِ مَا عَلَى عُثْمَانَ مَا عَمِلَ بَعْدَ هَذِهِ "