采用液相法, 在醇-水体系中, 以Mg(NO3)2?6H2O为镁源、PEG-2000为表面活性剂、NH3?H2O为沉淀剂, 研究了pH值和焙烧温度对制备MgO纳米片晶体性质的影响。采用XRD、SEM和BET等手段对MgO纳米片晶相组成、微观形貌、孔结构进行分析表征。研究结果表明, pH值和焙烧温度对MgO纳米片晶相组成没有影 响, 但对样品微观形貌和比表面积影响较大。较低的pH值和焙烧温度或者较高的pH值和焙烧温度均会导致样品形状不规则, 出现不同程度团聚, 比表面积较小 。在pH=10、焙烧温度500 ℃条件下制得MgO纳米片形状规整、分散性较好, 比表面积、孔容和平均孔径分别为145.42 m2?g-1、0.67 mL?g-1和18.56 nm。

Effect of pH value and calcination temperature on the crystalline properties of MgO nanosheets was investigated via liquid phase method in alcohol-water system with Mg(NO3)2?6H2O as magnesium, PEG-2000 as surfactant and NH3?H2O as precipitant. The crystal phase composition, morphology and pore structure of MgO nanosheets were characterized by XRD, SEM and BET. The results indicate that pH value and calcination temperature have no effect on the phase composition of MgO nanosheets, but posed significant impact on the micro- morphology and specific surface area of MgO nanosheets. Lower pH value and calcination temperature, or higher pH value and calcination temperature cause irregular shape and different degree of agglomeration of samples, with smaller specific surface area. The products has regular shape and good dispersibility under the condition of pH=10 and calcination temperature of 500 ℃, specific surface area of 145.42 m2?g-1, pore volume of 0.67 cm3?g-1 and average pore diameter of 18.56 nm.