Sieving transport within wavy-rough nanoannuli

We demonstrate the molecular sieving could be realized via a wavy-rough nanoannulus. By using the boundary perturbation method, we analytically obtain the flow rate (up to the second order) inside the wavy-rough nanoannuli. Our results show that for smaller forcing (along the nanoannulus-axis direction) there are significantly different flow rates for different amplitudes of wavy-roughness. This implies the fine-tuning of the solid-fluid interface of nanoannuli could be an efficient way for the molecular sieving.