均匀沉淀法制备碱式碳酸锌的过程研究  

Study on the Preparation of Zinc Carbonate Hydroxides by Homogeneous Precipitation Method

作　　者：邸琬茗[1] 宁文生[1] 金杨福[2] 王添琦[1] 

机构地区：[1]浙江工业大学化学工程学院,杭州310032 [2]浙江工业大学材料科学与工程学院,杭州310032

出　　处：《材料导报》2015年第18期60-64,共5页Materials Reports

基　　金：浙江省自然科学基金(LY14B030003);国家科技支撑计划(2014BAD02B05)

摘　　要：以硝酸锌和尿素为反应物,采用均匀沉淀法,通过改变均匀沉淀温度、反应物物质的量比,考察了反应时间对所形成沉淀的Zn原子利用率的影响,并利用X射线衍射(XRD)和扫描电子显微镜(SEM)对不同时刻的沉淀晶相和形貌进行表征。结果表明,反应开始时,发生了pH值先下降、再上升现象;反应20min时生成的产物中含有ZnO晶体,但在反应40min及之后生成的产物中只检测到Zn4CO3(OH)6·H2O和Zn5(CO3)2(OH)6晶体,并存在前者向后者转化的现象;碱式碳酸锌呈现球形片状组装体结构,经焙烧形成的ZnO晶体保持了碱式碳酸锌的形貌,随焙烧温度升高,ZnO晶粒长大。Zinc carbonate hydroxide was synthesized by the homogeneous precipitation method from urea and zinc nitrate. The influence of reaction duration on the utilization of Zn atom from solution into precipitate was investi- gated under different temperature, molar ratio of Zn to urea. XRD and SEM were used to characterize the crystal phase and morphology of the precipitates, respectively. During the first 20 minutes when the solution was heated from room-temperature to about 85℃ the pH value firstly decreased and then increased. ZnO crystal was detected in the precipitates formed during the first 20 minutes, but only Zn4COa （OH）6 · H20 （Zn4） and Zn5 （CO3）2 （OH）6 （Zn5） were found in the precipitates with extended reaction time longer than 40 minutes. The partial transformation of Zn4 into Zn5 was found according to the XRD results, which result in a slowly decreased pH value after 30 minutes in the reaction. Zinc carbonate hydroxides appear as sphere particles assembled by plate-like unit. After calcination, ZnO crystal was formed which maintained the same morphology as zinc carbonate hydroxides with much pores in the plate- like unit. The size of ZnO crystal raised with the increase of calcination temperature.

关 键 词：均匀沉淀法 硝酸锌 尿素 碱式碳酸锌 形成过程 

分 类 号：O614[理学—无机化学]