The preparation and performance tuning of Co/Ni based catalysts for chlorine evolution reaction.

[Display omitted] • Co/Ni based CER catalysts are prepared via electrodeposition and calcination. • The best catalyst is from the electrolyte with a Co/Ni ratio of 1:1. • The best calcination temperature for CER catalysts is 350 °C. • The optimal catalyst is successfully applied in antifouling of optical windows. Optical windows in the ocean suffer from bio-fouling inevitably, and electrochemical chlorination is considered to be a highly effective protective method. In this research, Co/Ni based chlorine evolution reaction (CER) catalysts were prepared using electrodeposition followed by calcination treatment. The results demonstrated that the stability and activity of the catalysts were influenced by the Co/Ni ratio of the electrolytes and calcination temperature, and the highest CER catalytic activity was achieved at a Co/Ni ratio of 1:1 and the calcination temperature of 350 °C. The calcinated catalyst (1:1, 350 °C) exhibited a CER selectivity of over 85 % across a current density range of 1 to 20 mA/cm². Additionally, it held excellent stability. The active chlorine produced via chronopotentiometry on this catalyst exhibited a nearly 100 % bactericidal efficiency against both Pseudomonas aeruginosa and Staphylococcus aureus after a 20 min electrolysis period. Moreover, a designed electrochemical chlorination accessory integrated with the catalyst was applied successfully for the bio-fouling prevention of optical windows in seawater. [ABSTRACT FROM AUTHOR]