pH Regulates Ion Dynamics in Carboxylated Mixed Conductors

TL;DR

This paper demonstrates that pH levels influence ion transport, doping, and mechanical properties in carboxylated polythiophenes, providing insights for designing pH-responsive soft electronic materials.

Contribution

It reveals how protonation states in carboxylated polythiophenes control ion dynamics and mechanical stability, introducing a new approach to tune mixed conductors via pH.

Findings

Protonation state affects ion transport and doping efficiency.

pH controls solvent uptake and mechanical response.

Molecular acidity guides design of responsive electronic materials.

Abstract

Coupled ionic and electronic transport underpins processes as diverse as electrochemical energy conversion, biological signaling, and soft adaptive electronics. Yet, how chemical environments such as pH modulate this coupling at the molecular scale remains poorly understood. Here, we show that the protonation state of carboxylated polythiophenes provides precise chemical control over ion dynamics, doping efficiency, solvent uptake and mechanical response. The findings establish molecular acidity as a general strategy to program ionic preference and mechanical stability, offering design principles for pH-responsive mixed conductors and soft electronic materials that couple ionic, electronic, and mechanical functionality.