Fe-doped CoP nanoframes (Fe-CoP NFs) were synthesized using a two-step method involving the self-assembly of cobalt iron Prussian blue analog nanoframes (CoFe PBA NFs) as templates followed by phosphorization. The resulting Fe-CoP NFs exhibit an open cage structure and enhanced catalytic activity for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER). The Fe-CoP NFs show overpotentials of 255 and 122 mV at 10 mA cm⁻² for OER and HER, respectively, outperforming most transition metal phosphides. For overall water splitting, the cell voltage is 1.65 V at 10 mA cm⁻², which is significantly lower than that of classical nanocubic structures. The Fe-CoP NFs maintain their activity for over 100 hours, demonstrating superior stability compared to noble metal catalysts. The enhanced performance is attributed to abundant accessible active sites, reduced kinetic energy barriers, and favorable adsorption of O-containing intermediates. The study highlights the potential of Fe-CoP NFs as efficient and stable bifunctional catalysts for overall water splitting, offering a promising approach for developing earth-abundant catalysts.Fe-doped CoP nanoframes (Fe-CoP NFs) were synthesized using a two-step method involving the self-assembly of cobalt iron Prussian blue analog nanoframes (CoFe PBA NFs) as templates followed by phosphorization. The resulting Fe-CoP NFs exhibit an open cage structure and enhanced catalytic activity for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER). The Fe-CoP NFs show overpotentials of 255 and 122 mV at 10 mA cm⁻² for OER and HER, respectively, outperforming most transition metal phosphides. For overall water splitting, the cell voltage is 1.65 V at 10 mA cm⁻², which is significantly lower than that of classical nanocubic structures. The Fe-CoP NFs maintain their activity for over 100 hours, demonstrating superior stability compared to noble metal catalysts. The enhanced performance is attributed to abundant accessible active sites, reduced kinetic energy barriers, and favorable adsorption of O-containing intermediates. The study highlights the potential of Fe-CoP NFs as efficient and stable bifunctional catalysts for overall water splitting, offering a promising approach for developing earth-abundant catalysts.