Structural regulation of ferrocene-doping Cu-MOFs for enhancing thermoelectric properties of single-walled carbon nanotube-based composite films

The integration of metal organic frameworks and carbon nanotubes has attracted considerable attention as obtained composites show synergistic effects in application of thermoelectric conversion. In this work, ferrocene (Fc) is used to adjust the microstructures of HKUST-1, and Cu₃BTC_2-xFc_x (CBF_x, where x relates to the Fc content) is synthesized by hydrothermal method and composited with single-walled carbon nanotubes (SWCNTs). The interfacial interaction between CBF_x and SWCNTs is enhanced after the introduction of Fc, and the electrical conductivity of the composite films is improved, achieving a maximum room temperature power factor (PF) of 221.8 μW m⁻¹ K⁻². Moreover, the electrical conductivity and Seebeck coefficient of the composite films are further improved through the acid/base and redox treatment and achieved an optimum room temperature PF of 247.6 μW m⁻¹ K⁻² and 225.1 μW m⁻¹ K⁻², respectively. Therefore, this work combines the structure regulation strategy with the sample post-treatment, opening a new direction to further improving the thermoelectric properties of carbon nanotube-based films.