The case of hydronium ions (H₃O⁺) is an example of this. In the gase^([sic]) phase, hydronium is a weak acid. The data in Table 3.10 indicates that bare hydronium ions have a higher electron affinity than most metal surfaces, so a bare hydronium ion should be neutralized when it absorbs on a bare metal surface. However, a hydrated hydronium ion is a stronger acid.
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Acids are compounds that produce hydronium ions when mixed with water.[…]The hydronium ion is a very special ion because it is the defining particle of all acids.
Source: wiktionary
Hydronium is not a way of stabilizing an acid, because the structure itself is so quickly transient that it can be considered as not existing.
Source: wiktionary
There is experimental evidence for the formation of coordination groups of hydroniums with several water molecules by hydrogen bridges.
Source: wiktionary