Comment on “Osmotic Propulsion: The Osmotic Motor”

Osmotic propulsion: the osmotic motor.

A model for self-propulsion of a colloidal particle--the osmotic motor--immersed in a dispersion of "bath" particles is presented. The nonequilibrium concentration of bath particles induced by a surface chemical reaction creates an osmotic pressure imbalance on the motor causing it to move. The ratio of the speed of reaction to that of diffusion governs the bath particle distribution which is e...

Electro-osmotic propulsion of helical nanobelt swimmers

Micro and nanoscale mobile agents capable of self-propulsion in low Reynolds number fluids would have a great technological impact in many fields. Few known mechanisms are able to propel such devices. Here we describe helical nanobelt (HNB) swimmers actuated by an electric field-generated electro-osmotic force. These HNB swimmers are designed with a head and a tail, similar to natural micro-org...

Osmotic propulsion of colloidal particles via constant surface flux

Non-spherical osmotic motor: chemical sailing

The behaviour of a non-spherical osmotic motor an axisymmetric catalytic particle self-propelling in a dilute dispersion of reactant particles is considered. In concrast to a conventional osmotic motor that creates differences in concentration, and hence in osmotic pressure, due to asymmetry in reaction rate along its surface (e.g. a Janus particle with reactive and non-reactive patches), a non...

The Effect of Osmotic Dehydration on Reverse Osmosis Membrane Performance

Akin type (asymmetric) reverse osmosis membranes undergo an irreversible osmotic dehydration upon coming into contact (skin side) with salt solutions. The extent of consequent changes (in appearance; decrease in linear dimension, water flux and salt rejection) are dependent on the salt concentration. These observations are correlated with the expected morphological changes taking place duri...