To develop highly stable and active Ru complex catalysts for CO₂ hydrogenation, we synthesized Ru complexes bearing rigid pincer-type tridentate NNN (pyrazole-pyridine-pyrazole) ligands and weakly coordinated triphenylphosphine (PPh₃) ligands. The NNN ligands can strongly chelate with the Ru metal center, contributing to the overall robustness of the catalytic system. Meanwhile, PPh₃ can easily dissociate to form vacant coordination sites, thereby enhancing catalytic activity. As a result, the Ru(Ⅱ)-NNN complex [Ru(L-NNN)Cl(PPh₃)₂]Cl (1, L-NNN=2,6-bis(5-methyl-1H-pyrazol-3-yl)pyridine) was not only quite stable, but also showed high activity for CO₂ hydrogenation to formate, achieving a TON of up to 150 000. In the mechanism study, based on the results of in-situ NMR, in-situ HPLC-HRMS spectra, and density functional theory calculations, it is speculated that the active intermediates with empty coordination sites are highly active species in CO₂ hydrogenation.

Binary composites (ZIF-67/rGO) were synthesized by one-step precipitation method using cobalt nitrate hexahydrate as metal source, 2-methylimidazole as organic ligand, and reduced graphene oxide (rGO) as carbon carrier. Then Ru³⁺ was introduced for ion exchange, and the porous Ru-doped Co₃O₄/rGO (Ru-Co₃O₄/rGO) composite electrocatalyst was prepared by annealing. The phase structure, morphology, and valence state of the catalyst were analyzed by X-ray powder diffraction (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). In 1 mol·L^-1 KOH, the oxygen evolution reaction (OER) performance of the catalyst was measured by linear sweep voltammetry, cyclic voltammetry, and chronoamperometry. The results show that the combination of Ru doping and rGO provides a fast channel for collaborative electron transfer. At the same time, rGO as a carbon carrier can improve the electrical conductivity of Ru-Co₃O₄ particles, and the uniformly dispersed nanoparticles enable the reactants to diffuse freely on the catalyst. The results showed that the electrochemical performance of Ru-Co₃O₄/rGO was much better than that of Co₃O₄/rGO, and the overpotential of Ru-Co₃O₄/rGO was 363.5 mV at the current density of 50 mA·cm^-2.

Developing high-performance electrocatalysts for the alkaline hydrogen oxidation reaction (HOR) is essential for advancing alkaline hydrogen fuel cells. Here, we report the synthesis of ruthenium (Ru) catalysts with tuned crystallinity and oxidation degree. By combining template-assisted synthesis with controlled thermal treatment, amorphous, partially crystalline, highly crystalline, and partially oxidized Ru products were successfully obtained. Catalysts with moderate crystallinity and partial oxidation exhibit enhanced catalytic activity toward the alkaline hydrogen oxidation reaction. The optimized Ru-RuO₂ catalyst achieved a mass activity of 81.66 mA·mg_Ru^-1, which was 2.27 times that of commercial Pt/C under identical conditions. The improved activity is attributed to the synergistic effect of moderate crystallinity and partial oxidation, which favors a favorable Tafel-Volmer reaction pathway.

电催化硝酸盐还原(NO₃⁻RR)合成氨(NH₃)为含硝酸盐工业废水资源化处理利用一体化提供了一条理想的路径。然而，该反应涉及多电子/质子转移步骤，在质子供应不足时动力学缓慢，导致氨选择性与产率低。本研究基于“氢穿梭接力”策略，设计了一种负载于镍泡沫(NF)上的Pd-Ru双金属催化剂(Pd-Ru/NF)，发现Pd位点主导硝酸盐活化与加氢过程，而Ru位点则高效裂解水分子产生活性氢物种(H*)。二者协同构成氢传递网络，实现反应位点间的氢溢流动态匹配，从而在加速硝酸盐加氢的同时，有效抑制析氢副反应(HER)。在−1.4 V (vs. RHE)电位下，Pd-Ru/NF催化剂的氨产率高达1.77 mmol cm⁻² h⁻¹，法拉第效率(FE)为85.95%。本工作通过构建双功能位点协同的氢接力机制，为设计高效NO₃⁻RR催化剂提供了新范式。