[Ru(tmphen)₃]₂[Fe(CN)₆] and [Ru(phen)₃][Fe(CN)₅(NO)] complexes and formation of a heterostructured RuO₂–Fe₂O₃ nanocomposite as an efficient alkaline HER and OER electrocatalyst

Abstract

Water electrolysis is one the most capable processes to supply clean fuel. Herein, two novel ionic Ru(II)–Fe(II) complexes, [Ru(tmphen)3]2[Fe(CN)6] and [Ru(phen)3][Fe(CN)5(NO)] where tmphen ꞊ 3,4,7,8-tetramethyl-1,10-phenanthroline, and phen ꞊ 1,10-phenanthroline, were...

Ligand leaching enabling improved electrocatalytic oxygen evolution performance

“…The weak band at 3400 cm −1 suggests the presence of an –OH unit. The peaks at 2108 and ∼3300 cm −1 can be ascribed to the –CN 44 and –NH 2 units, while those in the range of 2800–3000 cm −1 are indexed to –CH 2 – species. The –NH 2 stretching vibration provides bands at 3330 and 3270 cm −1 , 38 while the corresponding bending vibration presents a band at 1590 cm −1 .…”

“…43 The bands located at 710.2 and 723.7 eV could be indexed to Fe 3+ species. 44 For Ni-dp-Fe/CNT-2, the main bands shift to 709.2 and 722.0 eV for Fe 2p 3/2 and 2p 1/2 , respectively, suggesting that the Fe 3+ species is reduced by NaBH 4 with strong reducing ability.…”

Low-loaded Ru on hollow SnO2 for enhanced electrocatalytic hydrogen evolution

“…34,35 Conversely, the Ru 3d 3/2 peak is broader as compared to the Ru 3d 5/2 peak due to overlapping with the C 1s peak (284.4 eV). 36 In Fig. 1c, the Sn 3d 5/2 peak in Ru–SnO 2 is positioned at 487.2 eV, and Sn 3d 3/2 at 495.7 eV, which shows a positive shift in peak position compared to that of pristine SnO 2 , demonstrating the presence of strong metal–support interactions between SnO 2 and Ru.…”

Recent Advances and Perspectives in Ru Hybrid Electrocatalysts for the Hydrogen Evolution Reaction

“…The bifunctional electrocatalytic activity of Ru and NiMoO on the HER was greatly enhanced with the overpotential of 37 mV to reach 10 mA cm –2 . The RuO 2 –Fe 2 O 3 nanocomposites derived from [Ru­(tmphen) 3 ] 2 [Fe­(CN) 6 ] were prepared by the one-pot method, which also improved the HER performance by utilizing the synergistic effect of the heterostructure and active site on the interface . A new unit cell with the Ru–O–Fe bond at the heterostructural interface between RuO 2 and Fe 2 O 3 nano-oxides was regarded as the active site of the electrocatalyst, which exhibited high activity for the HER with the overpotential of 148 mV at 10 mA cm –2 , respectively.…”

“…The RuO 2 −Fe 2 O 3 nanocomposites derived from [Ru-(tmphen) 3 ] 2 [Fe(CN) 6 ] were prepared by the one-pot method, which also improved the HER performance by utilizing the synergistic effect of the heterostructure and active site on the interface. 102 A new unit cell with the Ru−O−Fe bond at the heterostructural interface between RuO 2 and Fe 2 O 3 nanooxides was regarded as the active site of the electrocatalyst, which exhibited high activity for the HER with the overpotential of 148 mV at 10 mA cm −2 , respectively. As previously mentioned, MoS 2 was a potential electrocatalyst for the HER in alkaline media, but the slow ionization of water kinetics reduced the catalytic efficiency.…”