Devi Ngasepam Monica, Singh Naorem Khelchand
Department of Electronics and Communication Engineering, National Institute of Technology Nagaland, Dimapur, Nagaland, 797103, India.
Nanotechnology. 2020 May 29;31(22):225203. doi: 10.1088/1361-6528/ab76e9. Epub 2020 Mar 13.
In this work, glancing angle deposition (GLAD) has been used to grow Ag decorated CeO nanorod (NR) array on n-type Si substrate. The length of the NRs obtained was ∼235 nm and the size of the Ag NPs varied from 13 to 41 nm. The polycrystalline and crystalline nature of CeO and Ag respectively was revealed via selected area electron diffraction (SAED) analysis as well as x-ray diffraction (XRD) pattern. Optical absorption measurement depicts a distinct broad peak around 413 nm that is ascribed to the localized surface plasmon resonance (LSPR) effect of Ag NPs. The Ag decorated CeO NR device exhibited a turn on voltage at ∼3.2 V under dark, which then reduced to ∼1.3 V under 35 min illumination along with the increase in device current from 2.8 to 24.5 μA cm (4 V) on continuous exposure to light. Under white light illumination, a responsivity of 4.51 A W was obtained at 370 nm along with the detectivity and noise equivalent power (NEP) values of 4.15 × 10 jones and 0.01 pW respectively. Additionally, a fast response characteristic with rise and fall times of 74 ms and 42 ms respectively was demonstrated. Thus, these findings manifest the underlying LSPR mechanism at work in Ag/CeO heterojunction and reveal its high potential in UV photodetector application.
在本工作中，掠角沉积（GLAD）已被用于在n型硅衬底上生长银修饰的二氧化铈纳米棒（NR）阵列。所获得的纳米棒长度约为235 nm，银纳米颗粒（NP）的尺寸在13至41 nm之间变化。通过选区电子衍射（SAED）分析以及X射线衍射（XRD）图谱分别揭示了二氧化铈和银的多晶和结晶性质。光吸收测量显示在413 nm附近有一个明显的宽峰，这归因于银纳米颗粒的局域表面等离子体共振（LSPR）效应。银修饰的二氧化铈纳米棒器件在黑暗中显示出约3.2 V的开启电压，在光照35分钟后，随着器件电流从2.8 μA cm（4 V）持续增加到24.5 μA cm，开启电压降至约1.3 V。在白光照射下，在370 nm处获得了4.51 A W的响应度，探测率和噪声等效功率（NEP）值分别为4.15×10琼斯和0.01 pW。此外，还展示了分别具有74 ms和42 ms上升和下降时间的快速响应特性。因此，这些发现揭示了银/二氧化铈异质结中潜在的LSPR机制，并揭示了其在紫外光探测器应用中的巨大潜力。
