High catalytic activity of oxygen-induced (200) surface of Ta2O5 nanolayer towards durable oxygen evolution reaction

• A new, efficient, economical and durable Ta2O5 nanolayer OER catalyst is developed.
• First-principles calculations identify the highly active OER surface site.
• Oxygen-controlled surface modulation to activate catalytic activity is proposed.
• Oxygen-induced (200)-surface-exposed Ta2O5 shows high OER catalytic activity.

Efficient and durable catalysts towards oxygen evolution reaction (OER) are highly desirable for renewable energy technologies. Herein, we develop a new, efficient, economical and durable Ta2O5 OER catalyst by controlling oxygen environment to induce the active OER catalytic surface. Stable surface structures of Ta2O5 and their onset overpotentials towards OER are calculated via systematic DFT simulations. Oxygen site on the stable (200) surface of Ta2O5 is explicitly identified as the most active OER site, possessing a small calculated onset overpotential of 0.25 V. In addition, using the simulated oxygen-rich condition, we successfully grow a (200)-surface-exposed Ta2O5 nanolayer on a carbon cloth by oxygen-controlled pulsed laser deposition. In accordance to the simulation, the designated (200) surface exhibits high OER activity with an onset overpotential of 0.29 V and overpotential of 0.385 V at 10 mA/cm2. The oxygen-controlled surface modulation to activate catalytic activity provides a novel strategy for effective development of metal-oxide catalysts for clean energy technologies.

A new, economical and efficient Ta2O5 nanolayer catalyst towards durable oxygen evolution reaction is developed via oxygen-controlled surface modulation. First-principles calculations reveal that (200) surface of Ta2O5 possesses high OER catalytic activity. Controlling oxygen partial pressure induces the (200) surface of Ta2O5 nanolayer, activating its high OER catalytic activity.Figure optionsDownload as PowerPoint slide