The assembly of polyethyleneimine-entrapped gold nanoparticles onto filter paper for catalytic applications

A facile approach to assembling polyethyleneimine (PEI)-entrapped gold nanoparticles (Au PENPs) onto filter paper is reported. In this work, Au PENPs with an Au core size of 3.2 ± 0.8 nm were formed using PEI as a template, followed by adsorption onto filter paper. The formed Au PENP-containing filter paper was characterized by various techniques. We show that the Au PENPs are able to be adsorbed onto filter paper likely due to the microfibrous structure of the paper and the electrostatic interaction between the positively charged Au PENPs and the negatively charged filter paper. Furthermore, we demonstrate that the Au PENP-assembled filter paper displays an excellent catalytic activity and reusability to converting 4-nitrophenol to 4-aminophenol. Such a development of Au PENP-assembled filter paper may be applicable for the immobilization of other metal NPs onto filter paper for various applications in catalysis, sensing, and biomedical sciences.