纳米粒度与Zeta电位分析仪Zeta电位测试原理

麦克默瑞提克(上海)仪器有限公司Micromeritics Instrument (Shanghai)Ltd.The Science and Technology of Small Particles 麦克默瑞提克(上海)仪器有限公司Micromeritics Instrument (Shanghai) Ltd. 上海民生路550号1505-1509室， 邮编200135 Suite 1505-1509， 550 Minsheng Rd.， Shanghai， P.R. China 200135www.micromeritics.com www.micromertics.com.cn t.sina.com.cn/micromeritics Principle of Zeta Potential Measurement In most cases， colloidal particles possess a positive or negative electrostatic charge. Aselectrical fields are applied to the particle dispersion， the particles migrate in oppositely chargeddirections. As particles are irradiated in migration， scattering light causes Doppler shift dependingon electrophoresis mobility. NanoPlus software calculates the amount of Doppler shift followedby electrophoretic mobility and zeta potential by combining a heterodyne system and photoncorrelation method to perform Fourier transform (FFT) Slipping level Major part of medium ofobtained correlation function. Av=2Vnsin[/2]/入 U=V/E =nU/E ... Smoluchowski equation 4v：Doppler shift e： Detect angle E ：Electric field V：Velocity of particle 入：Wavelength of ：Zeta potentialmovement incidence light E .Permitivitu n.Refractive index U：Electrophoretic门 .Viscositu mobilitu Zeta Potential Measurement Features of the NanoPlus-2 and NanoPlus-3 Measures zeta-potential of a sample suspension with concentrations from0.001% to 40% Reliable measurements based on electrophoretic light scattering technologyconforms to ISO 13099-2 ，AAccurately measures both dilute and concentrated suspensions Capable of evaluating the surface charge on solid surfaces， film， etc. basedon electroosmotic probing The Science and Technology of Small Particles 上海民生路550号1505-1509室， 由编200135 Suite 1505-1509， 550 Minsheng Rd.， Shanghai， P.R. China 200135www.micromeritics.com www.micromertics.com.cn t.sina.com.cn/micromeritics ● Variety of sample cells available The NanoPlus is capable of obtaining high resolution zeta potential analyses even withmulti-component samples. In the examle on the right， a mixture of five polystyrene latexes ofdifferent particle sizes was measured. Five spectrums corresponding to each lotex componentwas detected. The Zeta potential of these components were in the range of -45mV to -107 mV 上海民生路550号1505-1509 室， 由编200135 Suite 1505-1509， 550 Minsheng Rd.， Shanghai， P.R. China 200135www.micromeritics.com www.micromertics.com.cn t.sina.com.cn/micromeritics Evaluation of Dispersion Stability by Zeta Potential/Particle Size As the absolute value of zeta potential is larger， many colloidal particles show gooddispersability as the electrostatic repulsion becomes stronger. However， as the zeta potentialregisters close to zero， the particles become unstable and are likely to aggregate (Unstable·Aggregation) 第页MIC China November 第页MIC ChinaNovember