“…It is approximately consistent with azide-terminated monolayers on planar Au [22,23] and Si [3,27] surfaces, and also on nanoparticles [50][51][52][53], as well as with azide-carried polymers [54,55]. These azide groups behave normally as organic groups, different from the direct bonding of AN 3 to silicon metal (SiAN 3 ), which was reported at 2168 cm À1 (v a (AN@N + @N À )), due to the proximity effect of silicon metals [8]. In our case, azides were attached on polymer brushes; therefore the density of azides is enhanced greatly, compared to monolayer azides [3,4,[7][8][9][22][23][24]26,48].…”