Effect of capping and particle size on Raman laser-induced degradation of &gamma

2020-02-17 16:14:46

nm laser Raman Fe2O3 gamma

责任者: Varadwaj, K.S.K.;Panigrahi, M.K.;Ghose, J. 单位: Dept. of Chem., Indian Inst. of Technol., Kharagpur, India 来源出处: Journal of Solid State Chemistry(J. Solid State Chem. (USA)),2004/11/,177(11):4286-92 摘要: Diol capped γ-Fe2O3 nanoparticles are prepared from ferric nitrate by refluxing in 1,4-butanediol (9.5 nm) and 1,5-pentanediol (15 nm) and uncapped particles are prepared by refluxing in 1,2-propanediol followed by sintering the alkoxide formed. X-ray diffraction (XRD) shows that all the samples have the spinel phase. Raman spectroscopy shows that the samples prepared in 1,4-butanediol and 1,5-pentanediol and 1,2-propanediol (sintered at 573 and 673 K) are γ-Fe2O3 and the 773 K-sintered sample is Fe3O4. Raman laser studies carried out at various laser powers show that all the samples undergo laser-induced degradation to α-Fe2O3 at higher laser power. The capped samples are however, found more stable to degradation than the uncapped samples. The stability of γ-Fe2O3 sample with large particle size (15.4 nm) is more than the sample with small particle size (10.2 nm). Fe3O4 having a particle size of 48 nm is however less stable than the smaller γ-Fe2O3 nanoparticles 关键词: iron compounds;laser beam effects;nanoparticles;nanotechnology;particle size;polymers;Raman spectra;sintering;X-ray diffraction;capping effect;particle size;Raman laser induced degradation;diol capped γ-Fe2O3 nanoparticles;refluxing;uncapped particles;sintering;X-ray diffraction;XRD;spinel phase;Raman spectroscopy;1,5-pentanediol;1,4-butanediol;1,2-propanediol;9.5 nm;15 nm;573 K;673 K;773 K;15.4 nm;10.2 nm;48 nm;Fe2O3