Porous ZnO films are synthesized by inorganic chelating sol-gel method,which is a novel sol-gel technique using zinc nitrate as starting materials and citric acid as the chelating reagent.The crystal structure,surface...Porous ZnO films are synthesized by inorganic chelating sol-gel method,which is a novel sol-gel technique using zinc nitrate as starting materials and citric acid as the chelating reagent.The crystal structure,surface morphology,porous and optical properties of the deposited films are investigated.X-ray diffraction pattern analysis shows that crystal structure of the ZnO films is hexagonal wurtzite.Scanning electron microscopy (SEM) shows that the ZnO film is porous.The curve of pore size distribution has two peak values at about 2.02nm and 4.97nm and BET surface area of the ZnO film is 27.57m2/g.In addition,the transmittance spectrum gives a high transmittance of 85% in the visible region and optical bandgap of the ZnO film (fired at 500℃) is 3.25eV.展开更多
基金National Natural Science Funds(51102184 and 51172163)National High Technology Research and Development Program of China+2 种基金National Key Technology R&D Program(2009BAC62B02)Doctoral Fund of Ministry of Education of China(20090072110047 and 20100072110054)Program for Young Excellent Talents in Tongji University(2010KJ068)
文摘Porous ZnO films are synthesized by inorganic chelating sol-gel method,which is a novel sol-gel technique using zinc nitrate as starting materials and citric acid as the chelating reagent.The crystal structure,surface morphology,porous and optical properties of the deposited films are investigated.X-ray diffraction pattern analysis shows that crystal structure of the ZnO films is hexagonal wurtzite.Scanning electron microscopy (SEM) shows that the ZnO film is porous.The curve of pore size distribution has two peak values at about 2.02nm and 4.97nm and BET surface area of the ZnO film is 27.57m2/g.In addition,the transmittance spectrum gives a high transmittance of 85% in the visible region and optical bandgap of the ZnO film (fired at 500℃) is 3.25eV.
文摘采用 ISG(Inorganic Sol-gel)工艺的浸渍涂覆技术制备γ-Al_2O_3多孔膜,探讨了薄膜的制备条件及影响因素,重点研究了浸渍提拉技术中提拉速度、浸渍时间,涂覆次数与成膜速度的关系,同时通过微波超声清洗考察了薄膜的附着力;用 XRD 图谱鉴定了薄膜的物质相并通过 BET 测试对薄膜的孔分布进行了分析表征,利用 SEM 对煅烧后的γ-Al_2O_3多孔晶化膜进行了微观结构观察。实验结果表明,溶胶呈现非牛顿流体特征;薄膜制备过程中提拉速度、浸渍时间、涂覆次数对膜厚的影响呈现明显的规律性;通过超声清洗前后的称重表明薄膜的附着力很好;XRD 图谱表征了制备的 Al_2O_3薄膜为γ相;SEM 观察和 BET 测试都表明薄膜为具有60nm 以下的微孔膜。
