奈米氧化鎳製備及熱特性分析

本研究以液相法（Liquid phase, LP1 及LP2）、溶膠-凝膠法（Sol-gel, SG）及沉澱氧化法（Precipitation-oxidation, PO1 及PO2）製備奈米級氫氧化鎳，並控制燒溫度得到奈米氧化鎳。以熱重分析儀（TG）、粉末X光繞射（XRD）、傅立葉紅外線光譜儀（FT-IR）及程溫還原系統（TPR）鑑定結構與特性。經XRD、FT-IR及TPR分析，得知在燒過程中，奈米氧化鎳的顆粒會受氫氧化鎳顆粒的影響，且還原溫度亦隨物種而異。改變不同先驅物與沉澱劑製備的氫氧化鎳具有結晶性與粒徑的差異，經XRD確知：結晶性較佳、粒徑較大的氫氧化鎳，經燒所得氧化鎳粒徑較大。改變氧化劑則可得到不同的產物：以H_2O_2當氧化劑（沉澱氧化法一，PO1）得到Ni(OH)_2；改以NaOCl當氧化劑（沉澱氧化法二，PO2）則得到NiO_x（x ～ 1.2）。兩者經燒所得奈米氧化鎳顆粒均較另二種方法小。比較採用的製備方法，依TG之分析將燒溫度控制在300℃，可得到5 nm以下的NiO：PO1 ～ PO2（3.5 nm）＜LP2（3.8 nm）＜SG（4.9 nm）＜LP1（6.5 nm）。

關鍵字

奈米氧化鎳；液相法；溶膠－凝膠法；沉澱氧化法

並列摘要

Three methods including liquid phase (LP1 and LP2), sol-gel (SG), and precipitation-oxidation (PO) have been adopted to synthesize nanosized Ni(OH)2 that was subjected to further calcination to form NiO nanoparticles (NPs). The characterization results from techniques of TG, XRD, FTIR and TPR indicated that the particle size of NiO NPs and reduction temperature were found to vary with the types of Ni(OH)_2 and NiO NPs from different preparation methods. Furthermore, the choice of precursors and oxidans used was found to result in the difference in crystallinity and particle size of NiO NPs derived from different synthetic routes. Based on the analytical results of thermogravimetry, the optimal calcination temperature was found to be 300℃ and under the stated condition we have obtained NiO NPs with sizes in the following order: PO1 and PO2 (3.5 nm) ＜ LP2 (3.8 nm) ＜ SG (4.9 nm) ＜ LP1(6.5 nm).

並列關鍵字

Nanosized nicke oxide ； Liquid phase ； Sol-gel ； Precipitation-oxidation

國際替代計量

奈米氧化鎳製備及熱特性分析

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