Unveiling Ruthenium(II) Diazadienyls for Gas Phase Deposition Processes: Low Resistivity Ru Thin Films and Their Performance in the Acidic Oxygen Evolution Reaction

Two novel ruthenium complexes belonging to the Ru(II)(DAD)(Cym) (DAD = diazadienyl) (Cym cymene) compound family are introduced as promising precursors. Their chemical nature, potential for vapor deposition (CVD), and possibly atomic layer (ALD) demonstrated. The development of nonoxidative CVD processes yielding high-quality Ru thin films is realized. Chemical analyses exercised that vitiate deceptive assumption Ru(DAD)(Aryl) being zero-valent through clear evidence redox noninnocence DAD ligand. different routes growth developed using Ru(tBu2DAD)(Cym). from both subjected thorough comparative allowed deduce similarities differences in film growth. with a thickness 30–35 nm grown on SiO2 yielded close-to-bulk resistivity values ranging 12 16 µΩ cm. Catalysis evaluation acidic oxygen evolution reaction (OER) results performances based overpotentials low 240 mV Tafel slopes 45–50 dec−1. Based degradation observed during electrochemical measurements, impact OER conditions layers critically assessed by complementary methods.