Angle aligned electrospun metal fibers and its potential for stretchable electrodes for wearable electronics

Figure 1 demonstrate the conventional parallel fiber align using two parallel bars. Where align bar is composed of aluminum. Figure 1 illustrates the schematic setup used to align fiber using the specially designed jig. It is... [ view full abstract ]

Figure 1 demonstrate the conventional parallel fiber align using two parallel bars. Where align bar is composed of aluminum. Figure 1 illustrates the schematic setup used to align fiber using the specially designed jig. It is essentially the same as the conventional electrospinning configuration except for the use of an align-jig put on the surface of collector. The parallel aligned and diagonal aligned arrays of the metal fibers were fabricated on stretchable rubber substrates using the alignment jig. After clamping those aligned fibers by two fixtures connected to the current−voltage measurement system, they were stretched in specific elongation directions and lengths using a mechanical apparatus. When the parallel aligned metal lines (formed using the parallel-type collector) were stretched parallel to their alignment direction up to 10 %, these metal lines were broken due to the applied tensile force. However, diagonal aligned fibers can avoid this parallel alignment between the metal fibers and this misalignment can dissipate the applied tensile force. For example, the sample of diagonal alignment could be stretched up to ~ 90 % in strain with an increase in resistance of ~ 40% (figure 2). This mechanical stretchability of the metal fiber was superior to that of ITO, which can be cracked by applying a tensile strain of ∼1%. The locally broken parts of the parallel aligned fibers that resulted from stretching them into their alignment direction with a 10% strain. After stretching further, the metal fiber with the cracked lines became nonconductive.