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
Poly (EA-MAn-APTES)/silica hybrid materials were successfully prepared fromEthyl acrylate (EA), maleic anhydride (MAn) and tetraethoxysilane (TEOS) in the presence of acoupling agent 3-aminopropyltriethoxysilane (APTE...Poly (EA-MAn-APTES)/silica hybrid materials were successfully prepared fromEthyl acrylate (EA), maleic anhydride (MAn) and tetraethoxysilane (TEOS) in the presence of acoupling agent 3-aminopropyltriethoxysilane (APTES),by free-radical solution polymerization and insitu sol-gel process. The mass fraction of TEOS varied from 0 to 25%. The hybrid materials werecharacterized by the methods of FT-IR spectra, solvent extraction, scanning electron microscope (SEM), transmission electron microscope (TEM), differential scanning calorimetry (DSC) andthermogravimetric analysis (TGA) measuring apparatus to get their structures, gel contents,morphologies, particle sizes and thermal performances. The results show that the covalent bonds arebetween organic and inorganic phases, gel contents in the hybrid materials are much higher, theSiO_2 phase is well dispersed in the polymer matrix, silicon dioxide exist at nanoscale in thecomposites and have excellent thermal stability.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Poly (EA-MAn-APTES)/silica hybrid materials were successfully prepared fromEthyl acrylate (EA), maleic anhydride (MAn) and tetraethoxysilane (TEOS) in the presence of acoupling agent 3-aminopropyltriethoxysilane (APTES),by free-radical solution polymerization and insitu sol-gel process. The mass fraction of TEOS varied from 0 to 25%. The hybrid materials werecharacterized by the methods of FT-IR spectra, solvent extraction, scanning electron microscope (SEM), transmission electron microscope (TEM), differential scanning calorimetry (DSC) andthermogravimetric analysis (TGA) measuring apparatus to get their structures, gel contents,morphologies, particle sizes and thermal performances. The results show that the covalent bonds arebetween organic and inorganic phases, gel contents in the hybrid materials are much higher, theSiO_2 phase is well dispersed in the polymer matrix, silicon dioxide exist at nanoscale in thecomposites and have excellent thermal stability.