Photocatalytic Cleavage of Self-Assembled Organic Monolayers by UV-Induced Charge Transfer from GaN Substrates

Charge transfer between GaN and organic self-assembled monolayers is demonstrated. Alignment of charge-transfer levels allows for photocatalytic cleavage of aliphatic chains on the semiconductor surface. By variation of the Fermi level within GaN and by comparison to SiC, it is shown that charge transfer can be suppressed and the stability of molecular monolayers can be enhanced in the absence of the appropriate energetic alignment.