Electrochemical water-splitting is an effective approach for producing hydrogen without producing any pollutants, but its large-scale development is hampered by the lack of low-cost and efficient electrocatalysts. Therefore, it is essential to explore efficient and low-cost non-precious catalysts for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Herein, W-doped Fe-P/IF amorphous nanoflake arrays (W-Fe-P/IF) are synthesized by corrosive avenue and following low-temperature phosphorization. Benefiting from the superhydrophilic surface, amorphous structure, nanosheet morphology and abundant active sites, the synthesized catalysts exhibited good catalytic performance. Therefore, the W-Fe-P/IF electrocatalyst onws low overpotentials of 35, 67, and 105 mV to achieve 10 mA cm−2 in 1 M KOH, 1 M KOH + seawater, and 1 M PBS, respectively. In addition, it also exhibits low voltage of 1.63 V to obtain 10 mA cm−2 coupled with excellent stability under 500 mA cm−2. The work provides a new strategy for the preparation of highly-efficient and low-cost non-precious electrocatalysts on renewable energy-related applications.