Surface synergy of nickel ammonium and polyethyleneimine for air-stable n-type SWCNT thermoelectric films
作者：Siqin Li, Zan Li, Yunfei Zhang*, Hui Liu, ChakYin Tang, ChiPong Tsui, Feipeng Du*
关键字：Polyethyleneimine, Single-walled carbon nanotubes, Thermelectric properties, Air stability
论文来源：期刊
具体来源：Surfaces and Interfaces
发表时间：2026年
Single-walled carbon nanotube (SWCNT)-based flexible thermoelectric films hold great promise for wearable electronics due to their exceptional flexibility and high electrical conductivity. However, the development of n-type SWCNT materials lags behind that of their p-type counterparts, primarily due to challenges in achieving both high thermoelectric performance and long-term air stability. In this study, stable n-type nickel ammonia-polyethyleneimine/SWCNT([Ni(NH3)6]2+-PEI/SWCNT) thermoelectric films have been prepared by immersing PEI/SWCNT films into [Ni(NH3)6]2+ solution. Through charge doping and interfacial stabilization, the incorpo-ration of [Ni(NH3)6]2+ enhances the thermoelectric performance of the PEI/SWCNT composite film. The com-posite film exhibited a maximum room temperature power factor of 129.4 μW m-1 K-2 with the electrical conductivity of 1206.9 S cm-1 at a [Ni(NH3)6]2+ doping concentration of 0.5 × 10-6 mol L-1. Remarkably, theincorporation of [Ni(NH3)6]2+ ions significantly enhances the air stability of the PEI/SWCNT film. The treated film retains 96.5% of its original Seebeck coefficient after 81 days. Furthermore, the [Ni(NH3)6]2+-PEI/SWCNT films have been used for manufacturing a thermoelectric device consisting of 3-pairs of p-n legs, which demonstrates an output power of 3.4 μW at a temperature gradient of 60 K. Therefore, this work presents a metal complex ion regulation strategy to enhance the thermoelectric performance and the air stability of PEI/SWCNT,highlighting their potential for applications in flexible electronics.