2.2. Instruments
Electrochemical measurements were performed on a CHI 650
electrochemical analyzer (Shanghai CH Instrument). A conventional
three-electrode system was used with modified glassy
carbon electrode (GCE) as the working electrode, saturated calomel
electrode as the reference electrode, and platinum (Pt) disk electrode
as the auxiliary electrode. Scanning electron microscopy
(SEM) images were obtained at 5.0 kV on a Sirion (FEI) field emission
scanning electron microscope.