Facile synthesis of IrO2 nanoparticles decorated @ WO3 as mixed oxide composite for outperformed oxygen evolution reaction.

Oxygen evolution reaction (OER) electrocatalysts play the critical role in efficiency and durability for different hydrogen production systems. We have successfully synthesized the earth abundant WO 3 coupled with IrO 2 as mixed oxide composite by a facile two-step chemical method. 50% reduction in noble metal contents (IW-50) followed by two times enhancement in activity, four-folds increase in bulk mass specific activity along with the stability of mixed oxide composite as compared to state –of –the art IrO 2 catalyst are affirmed. Superior performance of mixed oxide composites are perceived due to four times increase in electrochemical surface area, reduction of Tafel slope, four-fold increase of turn over frequency, electronic distortion in Ir-4f spectrum of IW-50 along with the bridging of lattice oxygen atoms between iridium and tungsten metals. We believe that it would open up the new avenues for effective utilization of noble metal with high valence tungsten metal in corrosive environment. Image 1 • Effective support of WO 3 with IrO 2 particles for efficient oxygen evolution reaction. • Mixed oxide composite with 50% noble metal contents robustly performs in acid media. • Electronic distortion in Ir-4f spectra along with bridging of lattice oxygen atoms. • Improvement of numerous electrochemical properties as compared to homemade IrO 2. [ABSTRACT FROM AUTHOR]