Title:
One-dimensional GaN nanostructures: preparation, characterization and photocatalytic properties

Speaker:
Defa Wang

TU-NIMS Joint Research Center, School of Materials Science and Engineering, Tianjin University
92 Weijin Road, Nankai District, Tianjin 300072, China

Abstract:
One dimensional GaN nanostructures are synthesized by means of molecular beam epitaxy (MBE) and chemical vapor deposition (CVD), respectively. Firstly, wafer-level photocatalytic overall water splitting is obtained over MBE grown GaN nanowire arrays with the incorporation of a Rh/Cr₂O₃ core-shell co-catalyst, through which H₂ evolution is promoted by the noble metal core (Rh) while the possible water forming back reaction over Rh is effectively prevented by the Cr₂O₃ shell that acts as O₂ diffusion barrier.

Secondly, high quality zig-zag GaN nanowires are synthesized through the Au-catalyzed CVD process. In comparison with the straight nanowires, zig-zag GaN nanowires is found to possess significantly enhanced separation ability of the photogenerated electrons and holes owing to the spatial structure of alternate Ga-terminated facets and N-terminated facets, realizing photocatalytic overall water splitting consequently.