Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
7881099 | Acta Materialia | 2014 | 6 Pages |
Abstract
Efficient photoelectrochemical (PEC) water splitting was demonstrated by a doping-controlled GaN photoanode coated with NiO cocatalyst. Highly doped n-GaN was sandwiched between undoped GaN layers to effectively collect electrons through ohmic contact. With zero external bias, the photocurrent density of the optimized doping profile was â¼3.5 times higher than that of the undoped GaN reference. However, the increased doping concentration degraded the photoanode stability, which was attributed to crystalline defects generated in the highly doped n-GaN. NiO cocatalyst improved the long-term stability of the photoanode because of GaN/NiO band alignment, enhancing hole transport into NiO and suppressing PEC corrosion mediated by hole crowding in GaN. This work established a design strategy for increasing the photocurrent as well as improving stability during water splitting with a GaN-based photoanode.
Related Topics
Physical Sciences and Engineering
Materials Science
Ceramics and Composites
Authors
Jin-Ho Kang, Soo Hee Kim, Mohamed Ebaid, June Key Lee, Sang-Wan Ryu,