Comment on “Radical-mediated proton transfer enables hydroxyl radical formation in charge-delocalized water” by R. Zhao, Q. Zhang, N. Yang, L. Li, Z. Li and C. Cui, Chem. Sci. , 2025, 16 , 11954

Key Points

• To critique the claims made by Cui and colleagues regarding the formation of hydroxyl radicals in low pH water.
• Analyzed the thermodynamics of proton transfer processes.
• Evaluated the conditions under which hydroxyl radicals might form.
• Commented on the theoretical implications of charge-delocalized water and radical formation.
• Challenged the spontaneous formation of hydroxyl radicals at pH below 4.
• Demonstrated that proton transfer does not lead to the formation of hydroxyl radicals under claimed conditions.
• Indicated that claims lack thermodynamic support.