(1. 湖南理工學(xué)院化學(xué)化工學(xué)院，岳陽(yáng) 414006；
2. 中南大學(xué)化學(xué)化工學(xué)院，長(zhǎng)沙 410083)
摘 要: 采用球磨-水熱法合成不同投料摩爾比的Zn-Cu-Al層狀水滑石(LDHs)，LDHs前驅(qū)體經(jīng)焙燒后轉(zhuǎn)變?yōu)閆n-Cu-Al復(fù)合金屬氧化物。用XRD、SEM、TG、DTA和BET等方法對(duì)樣品前驅(qū)體及焙燒產(chǎn)物進(jìn)行表征。在模擬太陽(yáng)光照下，以甲基橙(MO)溶液為目標(biāo)降解物，研究金屬離子摩爾比、焙燒溫度等對(duì)樣品的結(jié)構(gòu)、組成形貌及光催化活性的影響。結(jié)果表明：當(dāng)n(Zn):n(Cu):n(Al)投料比為1:2:1時(shí)，獲得的前驅(qū)體具有典型的水滑石片層狀結(jié)構(gòu)。最佳前驅(qū)體經(jīng)500 ℃焙燒后樣品中出現(xiàn)ZnO、CuO和ZnAl2O4 3種氧化物的特征衍射峰，具有較好的結(jié)晶度，其比表面積為70.1 m2/g，孔體積為0.26 cm3/g。在模擬太陽(yáng)光照射下60 min后，0.5 g/L催化劑對(duì)25 mg/L甲基橙溶液的脫色率達(dá)93.1%。
關(guān)鍵字: Zn-Cu-Al；水滑石；復(fù)合氧化物；光催化降解；甲基橙
（1. School of Chemistry and Chemical Engineering, Hunan Institute of Science and Technology, Yueyang 414006, China;
2. College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China）
Abstract:Zn-Cu-Al layered double hydroxides (LDHs) with different molar ratios of Zn-Cu-Al were prepared viaball mill-hydrothermal method. Zn-Cu-Al composite metal oxide was derived from LDHS precursor by controllable calcination. The Zn-Cu-Al-LDHs samples before and after calcination were characterized by XRD, SEM, TG/DTA and BET measurements. The photocatalytic activity of the as-prepared samples was evaluated by photocatalytic decolorization of methyl orange (MO) aqueous solution under the irradiation of the simulated sunlight. The effects of the molar ratio of metal ion and calcination temperature on the structure, composition, morphology and photocatalytic activity were investigated in detail. The results shows that a layered double hydroxide (LDHs) precursor is obtained under initial molar ratio n(Zn):n(Cu):n(Al3+) of 1:2:1, after calcination at 500 ℃, which leads to a well-crystalline ternary oxide ZnO-CuO-ZnAl2O4 photocatalyst with BET surface area of 70.1 m2/g and pore volume of 0.26 cm3/g. The maximum photocatalytic decoloration rate of 25 mg/L methyl orange is 93.1% within 60 min under simulated sunlight irradiation at 0.5 g/L concentration of photocatalyst.
Key words: Zn-Cu-Al; LDHs; composite oxide; photocatalytic degradation；methyl orange
