摘要
以多壁碳纳米管(MWNTs)、氨水(NH_3·H_2O)和九水合硝酸铁[Fe(NO_3)_3·9H_2O]为原料,采用共沉淀法得到前驱体,经高温煅烧制得MWNTs/Fe_2O_3,利用XRD、TEM、UV-Vis和FT-IR等对其结构特性进行分析。以偏二甲肼废水为目标降解物评价了MWNTs/Fe_2O_3的光催化活性,并对光催化机理进行了分析。结果表明,MWNTs的引入可以改变氧化铁(Fe_2O_3)的晶型,同时使Fe_2O_3的粒径减小,并增加催化剂的吸附能力。另外,Fe—O—C化学键的形成使Fe_2O_3和MWNTs之间形成联合电子系统,有利于电子转移,电子-空穴对复合率有效降低。羟基自由基在MWNTs/Fe_2O_3光催化降解偏二甲肼过程中起主要作用。当pH值为7,MWNTs/Fe_2O_3用量为1.0g/L,光催化降解120min,对20mg/L的偏二甲肼的降解率可达98.1%,比相同条件下二氧化钛(TiO_2)的降解率高39.2%。
The precursor was prepared by coprecipitation process using MWNTs,NH3·H2O and Fe（ NO3）3·9H2O as raw materials,and MWNTs/Fe2O3 was prepared by the calcination of precursor. The samples were characterized by XRD,TEM,UV-Vis and FT-IR. Unsymmetrical dimethylhydrazine wastewater was chosen as target to evaluate the photocatalytic performance of MWNTs/Fe2O3,and the photocatalytic mechanism was discussed. The results showed that the introduction of MWNTs can change the crystal phase of Fe2O3,reduced the particle size of Fe2O3,and enhanced the adsorption capacity of catalyst. In addition,the formation of a joint electronic system between Fe2O3 and MWNTs by the formation of chemical bond Fe-O-C,which was conducive to the transfer of electrons,and e--h＋pair recombination probability was effectively reduced. Hydroxyl radical played a major role in the process of photocatalytic degradation of unsymmetrical dimethylhydrazine by MWNTs/Fe2O3. When pH was 7 and the amount of MWNTs/α-Fe2O3 was 1. 0g/L,after photocatalytic for 120 minutes,the degradation rate of unsymmetrical dimethylhydrazine reached 98. 1%. This result was better than that of TiO239. 2% at the same conditions.
出处
《化工新型材料》
CAS
CSCD
北大核心
2017年第7期177-179,183,共4页
New Chemical Materials
关键词
共沉淀
MWNTs/Fe2O3
偏二甲肼
光催化机理
coprecipitation
MWNTs/Fe2O3
unsymmetrical dimethylhydrazine
photocatalytic mechanism
