Universal diagram of particle deposition kinetics

Using microfluidics, we present a comprehensive description of particle deposition on solid surfaces for a broad range of experimental conditions (velocity, geometry, particle size, salt concentration). Here, we use microchannels where near the channel wall, particles are subject to different forces that control their trajectories: hindered diffusion, hydrodynamic forces, electrostatic forces, and adhesion. By coupling microfluidic experiments, theoretical analysis, and numerical simulations, we succeed in establishing a general description of particle deposition phenomenon by demonstrating the existence of three regimes: (attractive) van der Waals, (repulsive electrostatic) Debye, and Diffusive. In a certain coordinate system, the universal diagram that embodies these regimes can be represented by a cantilever beam, in which the vertical support is defined by a dimensionless number incorporating the properties of the Debye layer with respect to adhesion and the horizontal beam is determined by the comparison between an effective Peclet number (advection-diffusion transport) and the Hamaker constant (adhesion forces). Results show that the theory is supported quantitatively by experiments and numerics.