Efficient electrocatalysts are in great demand for renewable energy storage systems. Herein, we propose an ultrafast heating strategy to fabricate an efficient Ir/CP-UH catalyst for the oxygen evolution reaction (OER). Experimental results demonstrated that the ultrasmall Ir nanoparticles (≈1–3 nm) and clusters (<1 nm) were highly dispersed on the carbon paper support after a short thermal shock (∼5 s). The catalyst showed a low overpotential of 260 mV at 10 mA cm−2 and remarkable mass activity of about 13.8 times higher than that of the current state-of-the-art commercial Ir/C catalyst. This ultrafast heating strategy can also be applied to other catalyst systems for OER and other electrochemical reactions.
