A strategy for improving the stability of platinum-containing electrocatalyst toward hydrogen production in industrial alkaline water electrolysis

Significant breakthroughs have recently been made in boosting the hydrogen evolution reaction (HER) of Pt-containing electrocatalysts; however, it is unclear whether they can withstand long-term operational durability under the harsh industrial conditions, especially when driven by intermittent renewable energy. Here, a Pt-containing cathode was prepared by brushing a Pt-Ni solution onto Ni mesh (NM) (denoted as Pt-Ni/NM) and paired with a NM anode to study its stability under simulated industrial conditions (30 wt. % KOH, 60 degrees C). The assembled electrolyzer shows superior performance of water splitting, operating constantly under similar to 500 mA/cm(2) when the cell voltage is kept at 1.71 V. Unfortunately, the HER activity of the cathode degrades obviously when the cell voltage is under the "on/off" (1.71 V/0 V) states when simulating the supply of intermittent renewable energy. Comprehensive analyses revealed that the decline was attributed to the galvanic corrosion owing to the difference in redox potential between Ni and Pt. When the applied protective voltage on the "off" state exceeds such potential (similar to 0.58 V), the corrosion can be effectively alleviated, extending the stability to over 400 h. Furthermore, this protective strategy also shows effectiveness in improving the stability of other systems (e.g., Co-Ni), offering a promising way for practical applications in industrial alkaline water electrolysis.