The catalytic oxidation of NO plays an important role in the process of DeNO x . In this study, a series of Cu–Mn–O x mixed metal oxides were prepared by a co-precipitation method. The NO oxidation performances indicated that the catalyst with a Cu:Mn molar ratio of 1:1 prepared at pH 6 (denoted CuMnpH6) exhibited the best activity. In the presence of H2O, the activity of the CuMnpH6 catalyst was improved obviously compared to those of the other samples. The basicity of α-MnO2 was weakened after the addition of Cu. The basicity modification might inhibit the adsorption of H2O on surface oxygen atoms and likely promote the adsorption of NO over the CuMnpH6 catalyst. The redox properties were enhanced, and dual redox cycles existed during NO oxidation. The redox properties and surface basicity, which are related to the NO adsorption capacity, were correlated to the NO oxidation and resistance to H2O over Cu–Mn–O x catalysts.

As a traditional method of ammonia (NH3) synthesis, Haber–Bosch method expends a vast amount of energy. An alternative route for NH3 synthesis is proposed from nitrate (NO3−) via electrocatalysis. However, the structure–activity relationship remains challenging and requires in‐depth research both experimentally and theoretically. Here an N‐coordinated Cu–Ni dual‐single‐atom catalyst anchored in N‐doped carbon (Cu/Ni–NC) is reported, which has competitive activity with a maximal NH3 Faradaic efficiency of 97.28%. Detailed characterizations demonstrate that the high activity of Cu/Ni–NC mainly comes from the contribution of Cu–Ni dual active sites. That is, (1) the electron transfer (Ni → Cu) reveals the strong electron interaction of Cu–Ni dual‐single‐atom; (2) the strong hybridizations of Cu 3d—and Ni 3d—O 2p orbitals of NO3− can accelerate electron transfer from Cu–Ni dual‐site to NO3−; (3) Cu/Ni–NC can effectively decrease the rate‐limiting step barriers, suppress N–N coupling for N2O and N2 formation and hydrogen production.

The spillover of oxygen species is fundamentally important in redox reactions, but the spillover mechanism has been less understood compared to that of hydrogen spillover. Herein Sn is doped into TiO2 to activate low-temperature (<100 °C) reverse oxygen spillover in Pt/TiO2 catalyst, leading to CO oxidation activity much higher than that of most oxide-supported Pt catalysts. A combination of near-ambient-pressure X-ray photoelectron spectroscopy, in situ Raman/Infrared spectroscopies, and ab initio molecular dynamics simulations reveal that the reverse oxygen spillover is triggered by CO adsorption at Pt2+ sites, followed by bond cleavage of Ti-O-Sn moieties nearby and the appearance of Pt4+ species. The O in the catalytically indispensable Pt-O species is energetically more favourable to be originated from Ti-O-Sn. This work clearly depicts the interfacial chemistry of reverse oxygen spillover that is triggered by CO adsorption, and the understanding is helpful for the design of platinum/titania catalysts suitable for reactions of various reactants.