Conducting polymers such as poly(3,4-ethylenedioxythiophene):poly-(styrenesulfonate) (PEDOT:PSS) have attracted extensive attention for thermoelectric applications due to its solution-processability, mechanical flexibility, low thermal conductivity and tunable electrical conductivity. This work demonstrated a sequential post-treatment method with formamide and sodium formaldehyde sulfoxylate (SFS) to significantly improve thermoelectric properties of PEDOT:PSS film, particularly its Seebeck coefficients. Water-soluble and non-toxic SFS is an ionic-type reducing agent, which is used as an environmentally benign chemical reagent for the first time to treat PEDOT:PSS. First, the PEDOT:PSS film was soaked with formamide (F-PEDOT:PSS), and then was treated with SFS solutions with various molar concentrations (SFS–F-PEDOT). The Seebeck coefficient of F-PEDOT:PSS film treated with 100 mM SFS was steeply increased from 14.8 to 51.8 μV/K primarily due to the proper control of the doping level and the carrier concentration although the corresponding electrical conductivity of the film was reduced from 2,873 to 693 S/cm. The resulting power factor reached its maximum value of 185.8 μW/K²m, which was approximately three times that of formamide-treated film (F-PEDOT:PSS: 63.7 μW/K²m). The cross-plane thermal conductivity of the pristine PEDOT:PSS film was dropped from 0.59 W/mK for the pristine film to 0.29 W/mK for the SFS-F-PEDOT:PSS film, leading to an estimated ZT value of in the range of ∼0.07–∼0.14 at 300 K. Also, the stability of SFS-F-PEDOT:PSS film was examined under a harsh environment, and results showed that the film retained its electrical conductivity and Seebeck coefficient of more than 85% after continuous exposure under 70 °C and a humidity of 75% RH for 480 h, revealing the excellent long-term environmental stability.

诸如聚（3,4-乙撑二氧噻吩）：聚（苯乙烯磺酸盐）（PEDOT：PSS）的导电聚合物因其溶液加工性，机械柔韧性，低导热性和可调的导电性而引起了热电应用的广泛关注。这项工作证明了使用甲酰胺和甲醛次硫酸钠（SFS）进行的顺序后处理方法，可以显着改善PEDOT：PSS薄膜的热电性能，尤其是其塞贝克系数。水溶性且无毒的SFS是一种离子型还原剂，首次用作对环境无害的化学试剂来处理PEDOT：PSS。首先，将PEDOT：PSS膜用甲酰胺（F-PEDOT：PSS）浸泡，然后用具有不同摩尔浓度的SFS溶液（SFS–F-PEDOT）处理。用100 mM SFS处理的F-PEDOT：PSS薄膜的塞贝克系数从14.8陡增至51.8μV/ K，这主要是由于适当控制了掺杂水平和载流子浓度，尽管薄膜的相应电导率降低了。 2,873至693 S / cm。产生的功率因数达到最大值185.8μW/ K² m，约为甲酰胺处理过的薄膜（F-PEDOT：PSS：63.7μW/ K ² m）的三倍。原始PEDOT：PSS膜的横向平面热导率从原始膜的0.59 W / mK降至SFS-F-PEDOT：PSS膜的0.29 W / mK，导致ZT估计值在300 K时约为0.07-〜0.14。此外，在恶劣环境下检查了SFS-F-PEDOT：PSS膜的稳定性，结果表明该膜在连续条件下仍保持其电导率和塞贝克系数大于85％在70°C和75％RH的湿度下暴露480小时，显示出优异的长期环境稳定性。