Regio-Selective Functionalisation of Electrospun Materials at the Microscale

Electrospun nonwovens are highly versatile materials. Significant progress is achieved in terms of materials, methods, and setups, enabling a wide range of applications. However, regio-selective surface modification of electrospun fibers along their longitudinal axes remains an open challenge. This paper addresses this challenge and presents side-by-side electrospinning as a straightforward method for producing functional bead-on-string (BOS) fibers. The functional beads carry tertiary amino groups as a platform for further modifications. The beads are arranged in recurring distances along the fiber, allowing a precise fiber modification on the micron scale. This arrangement has been used for modifications with a fluorescent dye and gold nanoparticles (AuNP) in a highly precise and regio-selective manner. AuNP decorated BOS fiber nonwovens show excellent performance as heterogenous catalysts under flow conditions demonstrating low pressure drop, high turnover frequency, and recyclability.