The molten salt approach was used to convert CuAl₂O₄ nanoparticles to CuO nanorods in this study. Molten hydroxide (NaOH) synthesis was chosen over molten salts (NaCl/KCl) for removing aluminium oxide from copper aluminate at low temperatures. The molten salt process is environmentally beneficial. Polymeric precursors were used to make nanosized copper aluminates. Alginic acid polymer is used to gel aqueous solutions of copper acetate and aluminium nitrate, yielding precursor after further heating. The precursor provides 14 nm nanosized copper aluminates after being heated at 900°C for 5 hours. XRD, FTIR, SEM, and TEM were used to characterize the nanosized copper aluminate powder. Solid state mixing and solution technique were used to investigate molten hydroxide treatment of spinel CuAl₂O₄. The products of the reaction were identified using XRD. FTIR and SEM are also used to analyze the sample. Using UV-DRS absorbance spectrum analysis, the optical characteristics of CuAl₂O₄ and CuO nanorods were examined. Using the Tauc plot method, the band gaps of CuAl₂O₄ and CuO were calculated to be 4.3 and 3.93 eV.

中文翻译：

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CuAl2O4 纳米颗粒的合成及其向 CuO 纳米棒的转化

熔盐法用于转化 CuAl ₂ O ₄在本研究中将纳米颗粒转化为 CuO 纳米棒。选择熔融氢氧化物 (NaOH) 合成而不是熔融盐 (NaCl/KCl)，以在低温下从铝酸铜中去除氧化铝。熔盐工艺对环境有益。聚合物前体用于制造纳米尺寸的铝酸铜。海藻酸聚合物用于胶凝醋酸铜和硝酸铝的水溶液，进一步加热后产生前体。在 900°C 加热 5 小时后，前体提供 14 nm 纳米尺寸的铝酸铜。XRD、FTIR、SEM和TEM用于表征纳米尺寸的铝酸铜粉末。使用固态混合和溶液技术研究尖晶石 CuAl ₂ O _{4 的}熔融氢氧化物处理. 使用XRD鉴定反应产物。FTIR 和 SEM 也用于分析样品。使用UV-DRS 吸收光谱分析，检查了CuAl ₂ O ₄和CuO 纳米棒的光学特性。使用Tauc绘图方法，计算出CuAl ₂ O ₄和CuO的带隙为4.3和3.93 eV。