燃料对溶液燃烧合成ZnO纳米棒微观形貌和光催化性能的影响

Effects of Fuel on Morphology and Photocatalytic Performance of ZnO Nanorods Synthesized by Solution Combustion Method

以蔗糖、柠檬酸、乙二醇和尿素为燃料,Zn(NO3)2为氧化剂/锌源,采用溶液燃烧法合成ZnO纳米棒。借助XRD、SEM、比表面分析和光谱吸收等测试方法,考察了不同燃料对粉体的物相组成、微观形貌、比表面积和光催化性能的影响。结果表明:在点燃温度500℃下,各燃料配制的前驱体溶液均可发生燃烧反应合成六方相ZnO纳米棒,其平均径向尺寸小于100 nm,且以尿素为燃料合成的ZnO晶形更完整,以蔗糖为燃料合成的ZnO粉体具有最大的比表面积(24.83 m2/g)。光催化实验表明,以蔗糖为燃料合成的ZnO粉体光催化能力最佳,在高压汞灯照射60 min条件下,其对甲基橙溶液(10 mg/L)的降解率可达98.2%,且光催化反应符合一级动力学方程。

ZnO nanorods was synthesized by solution combustion method using sucrose, citric acid, glycol （or urea） as fuel, and Zn （NO3）2 as oxidant. Effects of fuels （namely sucrose, citric acid, glycol or urea） on phase composition, morphology, specific surface area and photocatalytic performance of as-synthesized ZnO were investigated by means of XRD, SEM, BET and absorption spectrum. The results show that ZnO nanorods （average radial size less than 100 nm） with a hexagonal crystal structure can be synthesized at ignition temperature of 500~C. ZnO owns the best crystallization or the highest specific surface area （24.83 mE/g） when using urea or sucrose as fuel, respectively. Photocatalytic tests show that as-synthesized ZnO using sucrose as fuel owns the best photocatalytic performance. The photodegradation efficiency to methyl orange solution （10 ml/L） is 98.2% under the high-pressure mercury lamp irra- diation for 60 min, and the reaction is described as the pseudo first order kinetics equation.