Cho Chungyeon, Son Jihun
Department of Carbon Convergence Engineering, College of Engineering, Wonkwang University, Iksan 54538, Jeonbuk, Korea.
Nanomaterials (Basel). 2019 Dec 23;10(1):41. doi: 10.3390/nano10010041.
A stretchable organic thermoelectric multilayer is achieved by alternately depositing bilayers (BL) of 0.1 wt% polyethylene oxide (PEO) and 0.03 wt% double walled carbon nanotubes (DWNT), dispersed with 0.1 wt% polyacrylic acid (PAA), by the layer-by-layer assembly technique. A 25 BL thin film (~500 nm thick), composed of a PEO/DWNT-PAA sequence, displays electrical conductivity of 19.6 S/cm and a Seebeck coefficient of 60 µV/K, which results in a power factor of 7.1 µW/m·K. The resultant nanocomposite exhibits a crack-free surface up to 30% strain and retains its thermoelectric performance, decreasing only 10% relative to the unstretched one. Even after 1000 cycles of bending and twisting, the thermoelectric behavior of this nanocomposite is stable. The synergistic combination of the elastomeric mechanical properties (originated from PEO/PAA systems) and thermoelectric behaviors (resulting from a three-dimensional conjugated network of DWNT) opens up the possibility of achieving various applications such as wearable electronics and sensors that require high mechanical compliance.
通过逐层组装技术交替沉积由0.1 wt%聚环氧乙烷（PEO）和0.03 wt%双层碳纳米管（DWNT）组成的双层膜（BL），其中DWNT分散有0.1 wt%聚丙烯酸（PAA），从而制备出一种可拉伸的有机热电多层膜。由PEO/DWNT-PAA序列组成的25层双层薄膜（约500 nm厚），其电导率为19.6 S/cm，塞贝克系数为60 μV/K，功率因子为7.1 μW/m·K。所得纳米复合材料在应变高达30%时表面无裂纹，并保持其热电性能，相对于未拉伸的材料仅降低10%。即使经过1000次弯曲和扭转循环，这种纳米复合材料的热电行为依然稳定。弹性体机械性能（源自PEO/PAA体系）和热电行为（由DWNT的三维共轭网络产生）的协同结合，为实现各种应用提供了可能性，如需要高机械顺应性的可穿戴电子设备和传感器。
