In-situ pulse electropolymerization of pyrrole on single-walled carbon nanotubes for thermoelectric composite materials

Electrochemical polymerization has become a powerful tool for constructing high-performance thermoelectric (TE) composite films, and attracted great attention from researchers. To date, however, there has been no report on the in-situ electrochemical polymerization of pyrrole (Py) on single-walled carbon nanotubes (SWCNTs). In this work, we developed a series of high-performance polypyrrole (PPy)/SWCNT composites by the in-situ pyrrole electropolymerization on the pre-fabricated SWCNT membrane electrode, where a pulse galvanostatic electropolymerization (PGEP) technology was adopted to perfect TE performance of the PPy/SWCNT composites via the interface engineering. As a result, the optimized PPy/SWCNT composite film achieved an excellent TE performance, with the largest power factor (PF) of 365.2 ± 9.6 μW m−1 K−2 and the maximum figure of merit (ZT) of 0.203 ± 0.005 at room temperature, which is well beyond the reach of the PPy-based binary TE composite materials reported previously. This work suggested that in-situ pulse electropolymerization would be an effective and feasible strategy for constructing high-performance TE materials, and also opened a new, promising avenue for improving TE materials in the future.