Screen-printed electrodes were produced on aDEK248 printing
machine (DEK, Weymouth, UK) using polyester screens
with appropriate stencil designs mounted at 45◦ to the printer.
Voltammetric measurements were taken using anAUTOLAB
PGSTAT 12 electrochemical system with GPES software (Eco
Chemie, Utrecht, The Netherlands).
Scanning electron microscopy (SEM) images were obtained
using a JEOL JSM-6460LV with an INCA elemental X-ray
analysis system.