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This study describes the chemical conversion and heat treatment of Ti6Al4V microspheres (Ti6_MS), and the resulting effects on their electrocatalytic properties. The wet‐chemical conversion (5.0 m NaOH, 60 °C, 24 h; Sample label: Ti6_TC) converts the top surface of the Ti6_MS powder into an ≈820 nm thick sodium titanate surface. Heat‐treatment (Ti6_TC_HT) at 450 °C increases the stability of the surface, through partial titanate crystallization, while mitigating excess rutile formation. All samples are analyzed chemically (XPS, EDX, Raman, EELS), structurally (XRD and TEM), and morphologically (SEM, TEM), demonstrating the characteristic formation of sodium titanate dendritic structures, with minimal chemical, structural, and morphological differences due to the 450 °C heat‐treatment. The effect of the preparation methodology on oxygen reduction reaction (ORR) electrocatalytic performance is also tested. The introduction of the sodium titanate layer changes the mechanism of the ORR, from a mixed 4 electron/2 electron pathway to a predominantly 2‐electron pathway. By maintaining the microspherical nature of the material while also tuning the surface of the material toward different reaction mechanisms, a design strategy for new electrocatalyst materials is explored. [ABSTRACT FROM AUTHOR]

Phosphate‐based glass fibers (PGF) are of interest as reinforcements for degradable implants, but have seen limited application due to their rapid loss of strength when subjected to aqueous conditions. Previous studies have utilized heat treatments to improve longer term strength retention at a significant cost to initial strength. In this study, acid etching is used to recover the initial fiber strength after heat treatment and a subsequent coating of polydopamine is applied to provide longer term retention of this recovered strength. After an initial loss of strength after heat treatment (1135 ‐> 509 MPa), an optimized combination of acid treatment and polydopamine coating was able to recover to approximately 85% of the initial strength (969 MPa). The result was significant in comparison to acid treatment (647 MPa) or coating (688 MPa) alone. The combined acid/coating treatment was demonstrated to maintain fiber properties for at least 14 days, although the amount of polydopamine coating was observed to decrease over this period. The approach reported here is of importance as it offers the required step change in degradation performance that is needed for PGF‐reinforced degradable composites. [ABSTRACT FROM AUTHOR]