Selective Production of Oxygen from Seawater by Oxidic Metallate Catalysts

Although the emphasis of water splitting is typically on hydrogen generation, there is a value in the oxygen byproduct especially for life support in field operations. For such applications, the production of a pure, unadulterated oxygen stream is highly desired under environmental conditions. Here, we demonstrate that self-healing oxygen evolution catalysts composed of cobalt or nickel are capable of selectively producing oxygen from both 0.5 M NaCl solutions and seawater. Differential electrochemical mass spectrometry demonstrates the absence of halogen in the product stream, and chemical analysis shows the production of only minute amounts of hypohalous acid.