Sepat Neha, Vagin Mikhail, Carli Stefano, Marchini Edoardo, Caramori Stefano, Zhang Qilun, Braun Slawomir, Wu Zhixing, Ding Penghui, Wijeratne Kosala, Petsagkourakis Ioannis, Ail Ujwala, Pavlopoulou Eleni, Ruoko Tero-Petri, Fabiano Simone, Tybrandt Klas, Fahlman Mats, Crispin Reverant, Berggren Magnus, Gueskine Viktor, Engquist Isak
Laboratory of Organic Electronics, Department of Science and Technology, Linköping University, Norrköping, 60174, Sweden.
Wallenberg Initiative Materials Science for Sustainability, Department of Science and Technology, Linköping University, Norrköping, 60174, Sweden.
Small. 2025 Feb;21(5):e2409471. doi: 10.1002/smll.202409471. Epub 2024 Dec 15.
The electrified production of hydrogen peroxide (HO) by oxygen reduction reaction (ORR) is attractive to increase the sustainability of chemical industry. Here the same chains of intrinsically conductive polymer, poly(3,4-ethylenedioxythiophene) (PEDOT) are utilized, as ORR electrocatalyst, while varying polymeric primary dopants (PSS and Nafion) and the level of secondary doping with DMSO. These changes modulate various properties of the film, such as its microscale organization and electronic conductivity. The aim here is to clearly decouple the rate of the heterogeneous electron transfer (HET) of ORR from the diffusion affected by electronic conductivity and the electrochemically available surface area. It is found that the rate of HET and the double layer capacitance are significantly affected by primary dopant. On the contrary, secondary doping shows very little effect on the rate of HET. However, such secondary doping resulted in the increase of both electrochemically available surface area and the diffusion through the polymer film. This effect is attributed to a few orders increase of the electronic conductivity in the film improving availability of the polymer for electron transfer. The enhancement of diffusion upon the secondary doping of conducting polymer is utilized to improve direct conversion of air into HO on gas diffusion electrode.
通过氧还原反应（ORR）电化学生产过氧化氢（HO）对于提高化学工业的可持续性具有吸引力。在此，利用了相同链长的本征导电聚合物聚（3,4 - 亚乙基二氧噻吩）（PEDOT）作为ORR电催化剂，同时改变聚合物主掺杂剂（PSS和Nafion）以及用二甲基亚砜进行的二次掺杂水平。这些变化调节了薄膜的各种性质，例如其微观组织和电子电导率。此处的目的是明确地将ORR的异质电子转移（HET）速率与受电子电导率和电化学可用表面积影响的扩散分离开来。研究发现，HET速率和双层电容受主掺杂剂的显著影响。相反，二次掺杂对HET速率的影响很小。然而，这种二次掺杂导致电化学可用表面积和通过聚合物薄膜的扩散都增加。这种效应归因于薄膜中电子电导率增加了几个数量级，从而提高了聚合物用于电子转移的可用性。利用导电聚合物二次掺杂时扩散的增强来改善气体扩散电极上空气向HO的直接转化。
