鉑奈米粒子修飾氧化鋅奈米柱以增強場發射和氣體感測特性

Decoration of ZnO nanorods with Platinum nanoparticles and their improved field emission and gas sensing performance

盧帝榮(Di-Rong Lu)

指導教授 ： 楊勝州

國立虎尾科技大學/電機資訊學院/電子工程系碩士班/碩士(2017年)

摘要

氧化鋅是Ⅱ-Ⅵ材料，有著寬直接能隙3.37eV，本研究藉由鉑奈米粒子修飾氧化鋅奈米柱（Pt / ZnO NRs）表面上。可以提高氧化鋅的電特性。在奈米柱生長之前，通過RF磁控濺射在玻璃基板上沉積100nm厚的ZnO晶種層。隨後，通過水熱法在90℃下生長氧化鋅奈米柱6小時，並通過RF磁控濺射系統將鉑奈米粒子濺鍍在氧化鋅奈米柱表面上。分析純氧化鋅奈米柱與鉑奈米粒子修飾氧化鋅奈米柱。結果表明，氧化鋅奈米柱的平均直徑和最大長度分別約為~50nm和~1.9μm。通過X射線衍射（XRD）測量純氧化鋅奈米柱與鉑奈米粒子修飾氧化鋅奈米柱的結構，所觀察到纖鋅礦結構（002），（102），（103）和（112）衍射峰。在90℃生長的氧化鋅奈米柱均勻生長且具有纖鋅礦結構。還發現，純氧化鋅奈米柱與鉑奈米粒子修飾氧化鋅奈米柱的場發射特型分析，在未照光的分析下Turn on電場分別為2.85和2.52V /μm，而電場增強因子β分別為702.19和1924.98。在氣體感測器方面，純氧化鋅奈米柱與鉑奈米粒子修飾氧化鋅奈米柱對甲醇1000ppm靈敏度分別為1.34與121.03。證明鉑奈米粒子有效提升靈敏度和響應，在工作溫度270℃和甲醇濃度為1000ppm時表現出良好的性能。成功利用水熱法製作場發射元件與氣體感測器元件。

關鍵字

鉑奈米粒子 ； 氧化鋅奈米柱 ； 場發射 ； 水熱法 ； 氣體感測

並列摘要

Zinc oxide is low-cost and practical Ⅱ-Ⅵ chemical materials, which utilized to absorb Platinum nanoparticle on zinc oxide nanorods (Pt/ZnO NRs). It can improve the electrical characteristics of the zinc oxide. Prior to NRs growth, a 100 nm-thick ZnO seed layer was deposited by RF magnetron sputtering on a glass substrate. Subsequently, the ZnO NRs were grown on these seed layers by the hydrothermal method at 90 °C for 6 hours and deposited Platinum nanoparticle on ZnO NRs by RF magnetron Sputter system. A set of samples have been prepared for different concentration of Pt precursors and named as ZnO, and Pt/ZnO NRs with 0s, and 30s sputter deposited times, respectively. The results indicate that ZnO NRs which have an average diameter and maximum length of around ~50nm and ~1.9 um, respectively. The structural characteristics of the ZnO NRs and Pt/ZnO NRs were measured by X-ray diffraction (XRD).Using the Joint Committee on Powder Diffraction Standards (JCPDS), it was found that the peaks observed were related to the wurtzite structured ZnO (002), (102), (103), and (112) diffractions. The ZnO NRs grown at 90 °C were structurally uniform and well oriented with pure wurtzite structure. It was also found that turn-on fields were 2.85 and 2.52 V/μm while field-enhancement factors β were 702.19 and 1924.98 for the ZnO NRs and Pt/ZnO NRs in the dark, respectively. In the results with an operating temperature, the sensitivities of the ZnO NRs and Pt/ZnO NRs gas sensors were about 1.34, and 121.03, respectively. Hence, the sensitivity and response presented good performance at increasing operating temperatures 270°C and Methanol concentrations of 1000ppm. The hydrothermal method was successfully applied for making ZnO gas sensors with large-scale production and low cost.

並列關鍵字

Platinum nanoparticle ； ZnO nanorods ； field emitter ； gas sensors

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