How does this material degrade? Do the spikes break off? If so, does the nanometer-size spiky silicon dust persist in the environment, or are they destroyed or

How does this material degrade? Do the spikes break off? If so, does the nanometer-size spiky silicon dust persist in the environment, or are they destroyed or neutralized somehow? late edit: I think it might (?) be functionally similar to fine silica dust, because (says the linked paper) the spiky surface is passivated with SiO2. ("...confirmed the presence of a thin SiO2 surface passivation layer on both planar and nanostructured Si surfaces...")