摘要
Nanoparticles are generally characterized by their size,morphology and surface charge using such advanced microscopic techniques as SEM(scanning electron microscopy),TEM(transmission electron microscopy)and XRD(X-ray diffraction).The average particle diameter,size distribution and charge affect the physical stability and the entire distribution of the nanoparticles.In this paper,the PKF(palm kernel fibre)nanofluid was prepared and characterized using TEM,SEM and XRD.The TEM results showed a mixture of different particle sizes with the lowest size measuring a diameter of 100 nm.The SEM showed particles of different shapes and distributions with some possible level of agglomerations.The stability of the nanofluid was evaluated using sedimentation by retention time and the spectrophotometric method.In the retention time method,the volume of the supernatant of the nanofluid sample was carefully measured using a 25 mL beaker and a pipette,and the solution was left for a period of time(two weeks),and then the supernatant was measured again.A constant volume supernatant was obtained though with little sedimentation,and that indicated a stable solution.UV-Vis(ultra aviolet-visible spectrophotometer)spectrum of the nanoparticles prepared with 0.01,0.02 and 0.03wt%concentrations were measured.The absorbance was measured with a start wavelength 230 nm and an end wavelength of 900 nm.The peak absorbance for each of the volume fractions was observed at 290,299 and 298 nm wavelengths by scanning.A quantum leap in wavelength above the listed range was an indication of instability at some point in the fluid.A good particle size correlation between the SEM,XRD and TEM measurements was observed.
