| 학회 |
한국재료학회 |
| 학술대회 |
2021년 가을 (11/24 ~ 11/26, 경주 라한호텔) |
| 권호 |
27권 2호 |
| 발표분야 |
E. 환경/센서 재료 분과 |
| 제목 |
Optimal atomic layer deposited Al-doped ZnO overlayers for charge transport enhancement in Cu2O photocathodes |
| 초록 |
Among the various technologies for the sustainable production of hydrogen, photoelectrochemical (PEC) water splitting is a promising and low-cost method with almost zero carbon emissions. Cu2O is one of the most promising p-type semiconductors for reducing water to hydrogen owing to the suitable conduction band position and its good visible absorption. To improve the charge transport efficiency of Cu2O photocathodes, the use of n-type overlayers with a proper band alignment can be an effective strategy. Atomic layer deposition (ALD)-prepared AZO films show an additional built-in potential at the Cu2O/AZO interface as well as an excellent conformal coating with a thin thickness on irregular Cu2O. Considering the atomic stacking process in ALD, it is expected that the composition of the Al and the layer stacking sequence will significantly influence the charge transport behavior of the photoelectrodes. We designed various atomic stacking orders of AZO overlayers where the stacking layers consisted of Al2O3 and ZnO using the atomically controlled ALD process. Al doping in ZnO results in a wide bandgap and does not degrade the absorption efficiency of Cu2O. The best PEC performance was obtained for the sample with an AZO overlayer containing conductive Al layers in the bottom and top regions. The Cu2O/AZO/TiO2/Pt photoelectrode with this overlayer exhibits an open circuit potential of 0.63 V and maintains a high cathodic photocurrent value of approximately -3.2 mA cm-2 at 0 VRHE for over 100 min. |
| 저자 |
이학현, 김동수, 최지훈, 조형균
|
| 소속 |
성균관대 |
| 키워드 |
Cu<SUB>2</SUB>O; photocathode; atomic layer deposition; AZO
|
| E-Mail |
|
