A residue-free approach to water disinfection using catalytic in situ generation of reactive oxygen species

Globally, water disinfection is reliant on chlorination, but requires a route that avoids the formation of chemical residues. Hydrogen peroxide, a broad-spectrum biocide, can offer such an alternative, but is typically less effective than traditional approaches to water remediation. Here, we show that the reactive oxygen species—which include hydroxyl, hydroperoxyl and superoxide radicals—formed over a AuPd catalyst during the synthesis of hydrogen peroxide from hydrogen and air are over 107 times more potent than an equivalent amount of preformed hydrogen peroxide and over 108 times more effective than chlorination under equivalent conditions. The key to bactericidal and virucidal efficacy is the radical flux that forms when hydrogen and oxygen are activated on the catalyst. This approach could form the basis of an alternative method for water disinfection, particularly in communities not currently served by traditional means of water remediation or where access to potable water is scarce. Despite its biocidal properties, the use of hydrogen peroxide is still limited in the context of water disinfection. Here an approach is disclosed based on the generation of H2O2 in situ by means of an AuPd catalyst, which can compete with chlorination methods by generating a highly reactive radical flux.