In this study, γ-MnO2 coatings were successfully deposited on Ti substrates using two different methods of electrodeposition and flame spray. The resulting coatings were thoroughly evaluated for their photocatalytic (PC), electrocatalytic (EC), and photoelectrocatalytic (PEC) performance via the degradation of methylene blue (MB). Structural analyses confirmed the formation of the γ-MnO2 phase in both coatings, with the flame-sprayed coating exhibiting a rougher, more porous morphology and higher hydrophobicity, whereas the electrodeposited coating displayed a denser microstructure with higher mechanical stability. Mott-Schottky analysis revealed that the coatings were n-type semiconductors, with the flame-sprayed coating displaying a more negative flat-band potential (−1.20 VAg/AgCl). Voltammetric tests revealed an increased oxygen evolution potential (1.29 VAg/AgCl) and a higher electroactive surface area, along with higher surface hydrophobicity, resulting in superior EC performance (82.3 %) for the flame-sprayed electrode. Additionally, the flame-sprayed coating demonstrated enhanced photocatalytic activity (59 %) due to prolonged charge carrier lifetime. Despite these differences, both electrodes achieved comparable PEC efficiencies (∼96 %), highlighting the complex interplay between structural, electronic, and interfacial properties during PEC processes. These findings provide valuable insight into the structure–function relationships of MnO2 coatings and lay the groundwork for optimizing catalyst fabrication methods tailored for environmental remediation.
