20.500.12556/DiRROS-25299 Hydrolysis synthesis of iridium oxide ▫$(IrO_x)$▫ on carbon for acidic oxygen evolution influence of heat-treatment on structure and electrocatalytic activity Hydrolysis synthesis of iridium oxide (IrO[sub]x) on carbon for acidic oxygen evolution: influence of heat-treatment on structure and electrocatalytic activity The development of efficient and durable oxygen evolution reaction (OER) electrocatalysts is critical for advancing proton exchange membrane water electrolyzers (PEMWEs). This study presents a nanostructured iridium oxide anchored on high-surface-area carbon (IrOx/C) OER electrocatalyst, synthesized through ultrasonication-assisted deposition of hydrolysis-derived colloidal IrOx nanoparticles onto the carbon support. The as-prepared IrOx/C exhibits a mass activity exceeding five times that of unsupported benchmark commercial IrO2, attributed to its uniform nanoparticle distribution and enhanced surface chemistry. Post-synthesis heat-treatments at two different temperatures (200 or 300 °C) were employed to stabilize the catalyst structure. Notably, the sample treated at 200 °C retained 84% of its initial activity after accelerated stress testing, outperforming the commercial counterpart, which retained 67 % under identical conditions. Comprehensive structural and morphological analyses revealed that the heat-treatment increased the IrOx particle size and decreased the Ir³⁺/Ir⁴⁺ ratio while leaving the amorphous nature of IrOx unaffected, which combinedly led to the improved durability. These findings offer valuable insights into designing stable low-iridium OER electrocatalysts for acidic PEMWE applications. iridium oxide oxygen evolution reaction carbon support stability iridijev oksid stabilnost true false true Elsevier Nizozemska Angleški jezik Slovenski jezik © 2026 The Author(s). Neznano 2026-01-15 13:23:47 2026-01-15 13:23:48 2026-01-17 03:44:11 0000-00-00 00:00:00 2026 0 0 Nasl. z nasl. zaslona; Soavtor iz Slovenije: Sašo Gyergyek; Opis vira z dne 15. 1. 2026; str. 1-11 Vol. 81, [article no.] 108451 Jan. 2026 0000-00-00 Zaloznikova Objavljeno NiDoloceno 2025-06-24 2026-01-07 2026-01-08 54 2468-0230 10.1016/j.surfin.2026.108451 264844035 https://www.sciencedirect.com/science/article/pii/S2468023026000386 1 0d7e80f1-f20d-11f0-94a7-001a4af901a5 https://dirros.openscience.si/Dokument.php?lang=slv&id=38237 RAZ_Karade_Swapnil_Sanjay_2026.pdf RAZ_Karade_Swapnil_Sanjay_2026.pdf 1 27A10D54E136525918A994C5AE974443 0c9ccda5d4f6f86b69457229e0b9e04d5984e7293a16b8c7eedf20e04777ecab a0366e65-f20d-11f0-94a7-001a4af901a5 https://dirros.openscience.si/Dokument.php?lang=slv&id=38239 Institut Jožef Stefan 0 0 0