Electrochemical Decoration of Additively Manufactured Graphene Macroelectrodes with MoO₂ Nanowires: An Approach to Demonstrate the Surface Morphology

Additive manufacturing (AM) provides a unique platform for the rapid design and fabrication of complex structures. Printed structures can be used as is or as templates to be decorated with electrochemically deposited nanomaterials, which may be utilized as electrocatalytic sensing platforms. Novel methods are required to determine the electrochemical deposition morphology present on the electrode surfaces. Additively manufactured graphene macroelectrodes (AM-G_Ms) were fabricated using a commercially available feedstock and molybdenum dioxide (MoO₂) was successfully electrochemically deposited onto the electrode surface. The electrochemically deposited MoO₂ was analyzed using scanning electron microscopy (SEM), optical interferometry, Raman spectroscopy, and multifractal analysis (MFA). Although the electrochemical deposition of MoO₂ nanowires was clearly visible using SEM, MFA enabled quantification of the MoO₂ nanowires deposited at various time points (20–300 s). MFA was utilized to generate quantitative data, derived from f­(α) curves, to determine the area of the electrochemically deposited MoO₂ nanowires, including coverage, density, dispersion, and clustering. The AM-G_Ms, which were subjected to 300 s (maximum time period) of MoO₂ electrodeposition, demonstrated the greatest percentage area coverage (20.14%). The use of such mathematical systems offers an inexpensive method to characterize the parameters of electrochemically deposited materials.