The　pH　effects　play　a　critical　role　in　electro-catalysis,　yet　their　influence　on　the　structural　evolution　of　electrocatalysts　during　the　oxygen　evolution　reaction　(OER)　remains　underexplored.　In　this　study,　we　combined　in-situ　Raman　and　UV–Vis　spectroscopy　with　density　functional　theory　(DFT)　calculations　to　track　the　structural　evolution　of　electrodeposited　amorphous　cobalt　(oxy)hydroxide　under　different　pH　conditions.　Our　findings　reveal　distinct　responses　of　the　synthesized　catalyst　to　varying　electrolyte　pH　levels.　The　formation　of　relatively　ordered　β-CoOOH　structure　from　amorphous　cobalt　(oxy)hydroxide　under　alkaline　conditions　may　serve　as　the　active　phase,　while　the　less　active　amorphous　cobalt　(oxy)hydroxide　remained　stable　under　neutral　conditions.　This　study　emphasizes　the　pivotal　role　of　electrolyte　pH　in　driving　surface　reconstruction　of　metal　oxides,　even　in　the　absence　of　applied　electrode　potential.　©　2025　Elsevier　Inc.