Annealed nichrome

Single carbon fibers (7-μm diameter, T650; Cytec Carbon Fibers LLC, Piedmont, SC, USA) were aspirated into borosilicate glass tubes (0.4 mm ID, 0.6 mm OD; A-M systems Inc., Sequim, WA, USA). The tubes were pulled to a fine tip around the fiber (Narishige puller, Los Angeles, CA, USA) and sealed with low viscosity epoxy (Spurr Epoxy; Polysciences Inc., Warrington, PA, USA). The exposed fibers were trimmed to a length of 200 μm. A droplet of mercury connected the fiber to a hookup wire (annealed nichrome; Goodfellow, Oakdale, PA, USA). The electrodes were soaked in isopropanol for at least 15 minutes prior to use (Bath et al., 2000 (link)).

Single carbon fibers (7 μm diameter, T650; Cytec Carbon Fibers LLC, Piedmont, SC, USA) were thread into borosilicate glass capillaries (0.4 mm ID, 0.6 mm OD; A-M systems Inc., Sequim, WA, USA) and pulled to a fine tip (8 μm OD) using a vertical electrode puller (Narishige puller, Los Angeles, CA, USA). Electrode tips were sealed using low viscosity epoxy (Spurr Epoxy; Polysciences Inc., Warrington, PA, USA). The exposed carbon fibers were trimmed to 400 μm length and electrical connection was established via a drop of mercury and a single nichrome wire (annealed nichrome; Goodfellow, Oakdale, PA, USA). Fully assembled electrodes were soaked in isopropanol (Bath et al. 2000 (link)) for 15 minutes prior to bare electrode calibration, prior to PEDOT/GO coating and prior to calibration post PEDOT/GO coating.