ACS CATALYSIS, vol.12, no.15, pp.9190-9200, 2022 (SCI-Expanded)
This study elaborates on the tunability of Zr and O amounts in the ZrO2 layer of a melt-spun Zr65Cu17.5Ni10Al7.5 ribbon under cyclic polarization. The formation of an amorphous Zr-rich oxide layer facilitates the oxygen evolution reaction (OER) as confirmed by the decrease in the Tafel slope from 109 to 80 mV dec(-1) as well as conservation of its stability over 250 cycles and at long-term open circuit potential measurement, outperforming many of the precious and transition metal-based oxides and their composites. The evolution of additional binding energy at similar to 183.5 eV (Zr3d5 Zr-OH peak) indicates hydroxide ion insertion into the Zr-based metallic glass. The magnitude of impedance (cf. 625 omega cm(2) for as-spun vs 140 omega cm(2) for after-OER at 0.6 V and 100 Hz) and characteristic frequency (c.f. 80 degrees at 0.6 V for as-spun and 30 degrees at 0.9 V for after-OER) vs Ag/AgCl are relatively small for the post-OER electrode compared to the as-spun counterpart, corroborating enhanced kinetics of the post-OER electrode. Modifications in the oxide layer upon the OER yield an enormous increase in ion accumulation and electron transfer with a maximum true capacitance reaching similar to 0.0271 F cm(-2). Thus, a homogeneous combination of inexpensive Earth-abundant metals and an amorphous structure forms a highly active and stable oxide layer to be used for future renewable energy production materials.