Ultraviolet photoelectrochemical photodetector based on GaN/Cu2O core-shell nanowire p-n heterojunctions

An efficient, self-powered ultraviolet photoelectrochemical photodetector based on n-GaN/p-Cu2O core-shell nanowire p-n heterojunctions is demonstrated. The photocurrent under solar light is 2-3 times larger than that for GaN nanowires. The photocurrents under the solar light and the ultraviolet light fraction are comparable, 100 mu A/cm(2) photocurrent density. The photocurrent under the broad visible light part is about 3% of that under solar light. The responsivity and specific detectivity reach 961.5 mu A/W and 5.35 x 10(9) Jones under ultraviolet light, respectively. The rise/fall times are 42/65 ms. This is understood by efficient photocarrier separation, hole collection, and transport in the near-surface GaN/Cu2O p-n heterojunction. (c) 2022 Author(s).

Automated summary

An efficient, self-powered ultraviolet photoelectrochemical photodetector based on n-GaN/p-Cu2O core-shell nanowire p-n heterojunctions is demonstrated. The photocurrent under solar light is 2-3 times larger than that for GaN nanowires. The photocurrents under the solar light and the ultraviolet light fraction are comparable, 100 muA/cm(2) photocurrent density. The responsivity and specific detectivity reach 961.5 muA/W and 5.35 x 10(9) Jones under ultraviolet light, respectively. The rise/fall times are 42/65 ms. This is understood by efficient photocarrier separation, hole collection, and transport in the near-surface GaN/Cu2O p-n heterojunction.