The integration of a fully printed carbon nanotube-based thermoelectric generator as a functional structural lamina within CFRP laminate composite: Powering electronic devices and wireless data transmission from multifunctional composites

Abstract

This work demonstrates the thermoelectric functionalization of a carbon fiber-reinforced polymer (CFRP) composite laminate utilizing single walled carbon nanotube-based (SWCNTs) targeted printing processes. Aqueous dispersions comprising carbon nanotubes of alternating n- and p-type materials were employed to print fiber reinforcements using facile ink dispensing methods. The optimum printed thermoelectric (TE) n- and p-type films, demonstrate the significant values of 109 and 148 μW/mK² οf power factor respectively. Under ambient conditions (1 atm, RH: 50 ± 5 %), the thermoelectrically functionalized CFRP operates steadily at temperatures as high as 140 °C. SWCNTs were printed via a mask-assisted process to form TE modules, yielding exceptional TE characteristics and high efficiency for a carbon-based structural element. The integrated SWCNT-based thermoelectric generator (TEG) within the CFRP demonstrates decent stability, achieving TE values of V_OC = 232 mV, I_SC = 510 μA, R_TEG = 455 Ω, and a maximum power of P_MAX = 30 μW under a ΔΤ = 50 K (T_COLD = 55°C). Additionally, the CFRP-TEG shows excellent bending strength and flexural modulus of 1044 MPa and 58 GPa, respectively, maintaining its mechanical properties while providing energy-harvesting capabilities. This structural energy-harvesting component is highly adaptable, enabling large-scale printed production of thermoelectrically-enabled laminate composites.