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.
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The data supporting the findings of this study are available within the article and its Supplementary Information or from the authors upon reasonable request, with the underlying data found at the Cardiff University Data Repository via https://doi.org/10.17035/d.2021.0132824835. Source data are provided with this paper.
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The authors acknowledge the research discussion with Dŵr Cymru Welsh Water and the Cardiff University electron microscope facility for the transmission electron microscopy. R.J.L. and G.J.H. acknowledge Cardiff University and the Max Planck Centre for Fundamental Heterogeneous Catalysis (FUNCAT) for financial support. S.J.F. acknowledges Cardiff University for financial support as part of the MAXNET Energy Consortium. In addition, S.J.F. acknowledges the award of a Prize Research Fellowship from the University of Bath. D.A.C. acknowledges Selden Research Limited. J.-Y.M. and G.M.S. thank Laboratoires Anios for funding. G.J.H. thanks the EPSRC (EP/F008538/1) for funding. Q.H. acknowledges support from the National Research Foundation (NRF) Singapore, under its NRF Fellowship (NRF-NRFF11-2019-0002).
The authors declare no competing interests.
Peer review information Nature Catalysis thanks Piedomenico Biasi, Bingcai Pan and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.
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Richards, T., Harrhy, J.H., Lewis, R.J. et al. A residue-free approach to water disinfection using catalytic in situ generation of reactive oxygen species. Nat Catal 4, 575–585 (2021). https://doi.org/10.1038/s41929-021-00642-w