In this study, CeO2 nanostructures were synthesized by a soft chemical method. A hydrothermal treatment was observed to lead to an interesting morphological transformation of the nanoparticles into homogeneous microsp...In this study, CeO2 nanostructures were synthesized by a soft chemical method. A hydrothermal treatment was observed to lead to an interesting morphological transformation of the nanoparticles into homogeneous microspheres composed of nanosheets with an average thickness of 40 nm. Structural analysis revealed the formation of a single-phase cubic fluorite structure of CeO2 for both samples. A Raman spectroscopic study confirmed the XRD results and furthermore indicated the presence of a large number of oxygen vacancies in the nanosheets. These oxygen vacancies led to room-temperature ferromagnetism （RTFM） of the CeO2 nanosheets with enhanced magnetic characteristics. Amazingly, the nanosheets exhibited substantially greater antibacterial activity than the nanoparticles. This greater antibacte- rial activity was attributed to greater exposure of high-surface-energy polar surfaces and to the presence of oxygen vacancies.展开更多
Here, undoped and Cu doped ZnO nanoparticles(NPs) have been prepared by chemical co-precipitation technique. X-ray diffraction(XRD) results reveal that Cu ions are successfully doped into ZnO matrix without altering i...Here, undoped and Cu doped ZnO nanoparticles(NPs) have been prepared by chemical co-precipitation technique. X-ray diffraction(XRD) results reveal that Cu ions are successfully doped into ZnO matrix without altering its wurtzite phase. The single wurtzite phase of ZnO is retained even for 10 wt% Cu doped ZnO sample. It is observed from the electron microscopy results that higher level of Cu doping varies the morphology of ZnO NPs from spherical to flat NPs. Moreover, the particle size is found to increase with the increase in Cu doping level. Raman spectroscopy results further confirm that Cu dopant has not altered the wurtzite structure of ZnO. Impedance spectroscopy results reveal that the dielectric constant and dielectric loss have increasing trend with Cu doping. Cu doping has been found to slightly decrease the bactericidal potency of ZnO nanoparticles.展开更多
基金funded by the Higher Education Commission of Pakistan (HEC) IPFP (Grant No. PM-IPFP/HRD/ HEC/2011/3386) to Dr. Javed Iqbal Saggu and funding for HEC Ph.D. Scholar (Tariq Jan) under his supervision
文摘In this study, CeO2 nanostructures were synthesized by a soft chemical method. A hydrothermal treatment was observed to lead to an interesting morphological transformation of the nanoparticles into homogeneous microspheres composed of nanosheets with an average thickness of 40 nm. Structural analysis revealed the formation of a single-phase cubic fluorite structure of CeO2 for both samples. A Raman spectroscopic study confirmed the XRD results and furthermore indicated the presence of a large number of oxygen vacancies in the nanosheets. These oxygen vacancies led to room-temperature ferromagnetism （RTFM） of the CeO2 nanosheets with enhanced magnetic characteristics. Amazingly, the nanosheets exhibited substantially greater antibacterial activity than the nanoparticles. This greater antibacte- rial activity was attributed to greater exposure of high-surface-energy polar surfaces and to the presence of oxygen vacancies.
基金funded by the Higher Education Commission, Pakistan (HEC) IPFP (Grant No. PM-IPFP/HRD/HEC/2011/3386)funding for HEC Ph.D. Scholar (Tariq Jan)
文摘Here, undoped and Cu doped ZnO nanoparticles(NPs) have been prepared by chemical co-precipitation technique. X-ray diffraction(XRD) results reveal that Cu ions are successfully doped into ZnO matrix without altering its wurtzite phase. The single wurtzite phase of ZnO is retained even for 10 wt% Cu doped ZnO sample. It is observed from the electron microscopy results that higher level of Cu doping varies the morphology of ZnO NPs from spherical to flat NPs. Moreover, the particle size is found to increase with the increase in Cu doping level. Raman spectroscopy results further confirm that Cu dopant has not altered the wurtzite structure of ZnO. Impedance spectroscopy results reveal that the dielectric constant and dielectric loss have increasing trend with Cu doping. Cu doping has been found to slightly decrease the bactericidal potency of ZnO nanoparticles.
