| 학회 |
한국재료학회 |
| 학술대회 |
2019년 가을 (10/30 ~ 11/01, 삼척 쏠비치 호텔&리조트) |
| 권호 |
25권 2호 |
| 발표분야 |
E. 환경/센서 재료 분과 |
| 제목 |
Boosting the photocatalytic hydrogen evolution performance via an atomically thin 2D heterojunction visualized by scanning photoelectrochemical microscopy |
| 초록 |
Heterojunction catalyst can facilitate efficient photoelectrochemical (PEC) hydrogen generation by reducing a potential barrier for charge transfer at the semiconductor/electrolyte interface. Such a heterojunction effect at the atomic thickness limit has not yet been explored although it can be strengthened because of strong built-in field and ultrafast charge transfer across the junction. Here, we first investigate a novel strategy to reduce the overpotential by employing an atomically thin heterojunction comprising MoS2 and WS2 monolayers as the hydrogen evolution reaction (HER) catalyst on the p-type photocathode. To unveil an effective role of the heterojunction by isolating its kinetic contribution from other collective catalytic effects, we develop and utilize a spatially resolved in situ PEC characterization platform, which enables the visualization of the enhanced photocatalytic HER performance of the heterojunction. Owing to the built-in potential generated by efficient charge separation in type-II heterojunctions, notably, significant reduction in both overpotential and interfacial charge-transfer resistance is achieved even without intentional generation of catalytic sites on the basal MoS2 surface. Furthermore, the beneficial role of the atomically scaled vertical heterojunction is supported by first-principles calculations. Our demonstration not only offers an unprecedented approach to investigating the fundamental PEC characteristics in relation to the tailored properties of a catalyst but also proposes a new catalytic architecture, thereby enabling the design of highly efficient PEC systems. |
| 저자 |
Jae Yoon Lee1, Sungwoo Kang2, DonghunLee1, Seokhoon Choi2, Seung Hoon Yang1, Kangwon Kim3, Yoon Seok Kim1, Ki Chang Kwon2, Sooho Choi4, Soo Min Kim5, Woong Huh1, Hee Seong Kang1, Hyeonsik Cheng3, Seungwu Han2, Ho Won Jang2, Chul-Ho Lee1
|
| 소속 |
1Korea Univ., 2Seoul National Univ., 3Sogang Univ., 4Dongguk Univ., 5KIST |
| 키워드 |
Photoelectrochemical hydrogen evolution; Transition metal dichalcogenides; Heterojunction; Catalyst; Spatially resolved PEC characterization
|
| E-Mail |
|
