Fig. 1: Morphological and structural characterization.
a Schematic diagram of the GaN/Si photoelectrode structure and the alkaline etching process of GaN NWs. b The crystal model diagram of GaN with wurtzite crystal structure. c The atomic arrangement of the (000\(\bar{1}\)) and (10\(\bar{1}\bar{1}\)) facet. N2f and N3f represent 2-fold coordinated N sites and 3-fold coordinated N sites, respectively. d SEM image of as-grown GaN NWs and faceted GaN NWs. e TEM image of as-grown GaN NWs and faceted GaN NWs. f HAADF-STEM image of the faceted GaN NWs (enlarged view of the pink box in e). g The high-resolution atom image of the faceted GaN NWs (enlarged view of the blue box in f).
