Nano sand filter with functionalized nanoparticles embedded in anodic aluminum oxide templates.

Nguyenthi Phuong,Jeasun Nham,Jeong Hwan Kim,Jae Sung Yoon,Yun Jung Lee,Anugrah Andisetiawan,Doo-Sun Choi,Do Van Lam,Yeong-Eun Yoo,Kyung-Hyun Whang

doi:10.1038/srep37673

Abstract

Since the ancient Egyptians had used sand as filter media for water purification, its principle has been inherited through generations and it is still being used now in industries. The sand filter consists of sand literally, and the voids within the sand bed are the pores for filtration. Here we present a filtration principle using nanoparticles, so that the voids between the nanoparticles can be considered as effective pores in nanoscale dimension. Anodic aluminum oxide (AAO) membrane has been used as the working template, and the nanoparticles have been injected and embedded within the pores of the AAO template. Nanoparticles with multiple sizes have been used in order to obtain smaller voids. Moreover, the nanoparticles have been functionalized, or electrically charged, with arginine/phenylalanine (RF) peptide group. In this way, filtration performance for charged particles or molecules, such as methylene blue, has been enhanced. Consequently, this study is expected to provide a new principle for fabrication of nano voids, or nano pores, and for filtration in nanoscale dimension.

Highlights

As electric charge selection[16,19,20], may provide comparable filtration performance with less flow resistance
This study introduces a nano sand filter, where nanoparticles are embedded in a porous template so that voids between nanoparticles can be considered as effective pores in nanoscale dimension
It needs to be mentioned that these images may not represent the exact arrangement of the nanoparticles in the anodic aluminum oxide (AAO) pores, because many of them have been lost when the AAO template is cut

Summary

Introduction

As electric charge selection[16,19,20], may provide comparable filtration performance with less flow resistance. The surfaces of nanoparticles have been functionalized to have arginine/phenylalanine (RF) peptide group, which has electric charge, in order to improve filtration performance for charged particles or molecules. Results Fabrication: Embedding nanoparticles within pores of AAO templates.

Results

Conclusion