funding (EP/R513143/1 and EP/T517793/1). PGF and BCS would like to thank Dr Raphael Pfattner for lending his technical expertise with the field effect transistor measurements and the custom-built MATLAB OFET software, as well as Dr Robert Malinowski and Prof Giorgio Volpe for their assistance with the contact angle measurements. The X-ray photoelectron (XPS) data collection was performed at the EPSRC National Facility for XPS ("HarwellXPS"), operated by Cardiff University and UCL, under Contract No. PR16195. CARC and JPAD would like to acknowledge funding from Queen Mary University of London School of Engineering and Materials Science and The Royal Society [RGS\R2\242541] as well as Dr Maria Crespo Ribadeneyra for the use of her PalmSens4 potentiostat.