Unprecedented Dipole Alignment in α-phase Nylon-11 Nanowires for High Performance Energy Harvesting Applications

Abstract

Dipole alignment in ferroelectric polymers is routinely exploited for applications in charge-based sensing, energy, memory and actuation. Here, we present the first experimental realisation of ideally ordered and stable dipole alignment in α-phase Nylon-11 nanowires. This is an unprecedented discovery as dipole alignment is typically only ever achieved in ferroelectric polymers using an applied electric field, referred to as electrical poling, whereas here, we achieve dipole alignment in α-phase, an overlooked polymorph of Nylon proposed 30 years ago but never practically realized due to its ‘non-ferroelectric’ characteristics. Importantly, we show that the strong hydrogen bonding in α-phase Nylon-11 serves to enhance the molecular ordering, resulting in exceptional intensity and thermal stability of surface potential. This discovery has profound implications for the field of triboelectric energy harvesting as the presence of an enhanced surface potential leads to higher mechanical energy harvesting performance. Our approach therefore paves the way towards achieving robust, high-performance mechanical energy harvesters based on this unusual ordered phase of Nylon-11.