Phase-transition-induced compressive strain regulates oxygen evolution pathway in Tet-ZrO2/RuO2 heterojunctions

Strain engineering has emerged as an effective strategy to modulate the electronic structure and adsorption energetics of oxygen evolution reaction (OER) catalysts. Among various approaches, phase-transition-induced strain offers distinct advantages due to its intrinsic origin, controllable magnitude, and structural stability, providing a self-adaptive route for dynamic catalytic regulation. Here, a lattice-matching strategy is employed to construct a tetragonal-phase ZrO 2 and tetragonal-phase RuO 2 (Tet-ZrO 2 /RuO 2 ) heterojunction catalyst. During synthesis, the phase transition of intermediate ZrO 2 (Int-ZrO 2 ) induces partial compressive strain on RuO 2 , leading to shortened Ru-O and Ru-Ru bond distances. The resulting Tet-ZrO 2 /RuO 2 catalyst exhibits outstanding activity in 0.5 M H 2 SO 4 , requiring only 193 mV overpotential to achieve 10 mA cm −2 and demonstrates remarkable stability, maintaining performance for 1000 h at 10 mA cm −2 with negligible degradation. Combining in situ attenuated total reflectance surface-enhanced infrared absorption spectroscopy (ATR-SEIRAS) with density functional theory calculation, it is revealed that the Tet-ZrO 2 /RuO 2 heterojunction enables the coexistence of both the adsorbate evolution mechanism (AEM) and the oxide path mechanism (OPM), jointly promoting O 2 generation. This work elucidates the regulatory role of lattice strain in tuning OER mechanisms through novel support design, providing a novel paradigm for developing highly active and stable electrocatalysts.