Long-term ageing of PEDOT:PSS: wettability Study

Known for its electric properties, poly (3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) has emerged as a good candidate for organic electronics and more recently for bio-applications. Despite its growing use in engineering applications, little is known about the stability in time of its interface properties. Here, we consider the surface ageing of PEDOT:PSS when it is stored in environments with various relative humidity and temperature conditions and as a function of the cross-linking agent's (3-glycidoxypropyltrimethoxysilane) concentration. Our systematic wettability study over 6 months reveals that the PEDOT:PSS interface undergoes significant reorganization and some irreversible changes on these timescales regardless of the concentration of cross-linker added.