In a recent article (J. Colloid Interface Sci. 578, 358{365 (2020)), we discussed the effect of Kapitza resistance on the stability and efficiency of photoacoustic conversion from gold nanorods, which we illustrated by means of an experimental model of rough particles exhibiting, with respect to their normal counterpart, larger specific surface area and so faster thermal coupling to their medium. We reported a striking improvement of both parameters, and we predicted more directions to modulate the effective value of Kapitza resistance and pursue technological impact as well as new applications. However, the route to the synthesis of rough gold nanorods involves multiple steps and nonstandard process parameters that might have affected their photostability, and so potentially led to an overestimation of the role of roughness. Here, we challenge our previous conclusions by isolating and testing the role of the most important among these factors, such as a thermal annealing under mild conditions and the deposition of a sacrificial shell of silver for galvanic replacement with gold. By a careful analysis of relevant thresholds, we conclude that both treatments actually exert no to a slight acceleration of the onset of photo-damage to gold nanorods. Therefore, our new findings collectively confirm and even reinforce the attribution of our original results to the office of roughness.
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