화학공학소재연구정보센터
학회 한국재료학회
학술대회 2018년 봄 (05/16 ~ 05/18, 삼척 쏠비치 호텔&리조트)
권호 24권 1호
발표분야 E. 환경/센서 재료 분과
제목 Facile Synthesis of Hollow Pd-Ag Composite Nanowires Arrays for Fast Responding and Transparent Wearable Hydrogen Sensors
초록 Pd based alloy materials with hollow nanostructures are ideal hydrogen (H2) sensor building blocks because of the ultra-high surface area afforded by this architecture. In this work, for the first time, we report a simple fabrication process for preparing hollow Pd-Ag alloy nanowires (Pd@Ag HNWs) by using the electrodeposition of lithographically patterned silver nanowires and followed galvanic replacement reaction (GRR) to form palladium. By controlling the GRR time of aligned Ag NWs within an aqueous Pd2+-containing solution, the compositional transition and morphological evolution from Ag NWs to Pd@Ag HNWs simultaneously occurred, and the relative atomic ratio between Pt and Ag was controlled. Interestingly, a GRR duration of 17 h transformed Ag NWs into Pd@Ag HNWs, that showed enhanced H2 response and faster sensing response time - reduced 2.5-fold – as compared to silver nanowires subjected to a shorter GRR period of 10 h. Furthermore, Pd@Ag HNWs patterned on the colorless and flexible polyimide (cPI) substrate showed highly reversible H2 sensing characteristics. To further demonstrate the potential use of Pd@Ag HNWs as sensing layers for all-transparent, wearable H2 sensing devices, we patterned the Au NWs perpendicular to Pd@Ag HNWs to form heterogeneous grid-type metallic NWs electrode which showed reversible H2 sensing properties in both bent and flat state.
저자 장지수, 김일두
소속 카이스트
키워드 LPNE; galvanic replacement reaction; alloy metal; hollow nanowire; sensor
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