Fig. 2: The tri-system integration and extremely smooth surface of the substrate-integrated uFTEs via the iSPM.

The ^AgNW-^AgNW interface. a, b The TEM images illustrating the respective Ag-PVP-Ag and Ag-Ag junctions regarding before and after the iSPM, respectively. c, d The ^ZnONP-^ZnONP interface. TEM images of the respective ^ZnONPs before and after the iSPM. The respective insets are the corresponding diffraction patterns. The ^AgNW-^ZnONP interface. e The as-prepared nanocomposite demonstrating the non-physical connection between ^AgNWs and ^ZnONPs in the presence of the PVP layer in the middle. f The TEM image magnifying near the interfacial region between ^AgNWs and ^ZnONPs. The representative FFT images were extracted from the corresponding (i), (ii), and (iii) boxes, showing an example of the well-matched lattice fringe between ^AgNWs and ^ZnONPs. There are many well-matched lattice fringe alignments that can be frequently found. The surface topography of the substrate-integrated uFTEs. g and h The SEM images of uFTEs according to with and without the tri-system integration, respectively. The respective insets are the corresponding magnified SEM images, illustrating ^ZnONP-poor (purple) and -rich (blue) surfaces, respectively. i and j, The AFM height profiles at the top-surface of the substrate-integrated uFTEs according to with and without the tri-system integration, respectively. The respective yellow lines are for measuring the corresponding average height profiles.