Oxygen vacancies are demonstrated to be beneficial to various electrocatalytic reactions. However, integrating oxygen vacancies into an amorphous catalyst with a large specific surface area, and investigating its effect on the oxygen evolution reaction remains a great challenge. Herein, oxygen vacancies are introduced into an amorphous N, P, and F tri‐doped CoFe2O4 using ionic liquid as a dopant. Simultaneously, ultrafine MoS2 nanoclusters are anchored onto its surface to increase the specific surface area. The vacancy‐rich MoS2/NPF‐CoFe2O4 exhibits an overpotential of 250 mV and a small Tafel slope of 41 mV dec−1, which is the best spinel‐based oxygen evolution reaction (OER) electrocatalysts so far. The excellent performance is attributed to massive oxygen vacancies, amorphous structure, large surface area, and synergistic coupling effects among active species. Density‐functional theory calculations reveal that the electronic structure of the catalyst can be modulated in the presence of heteroatoms and MoS2 nanoclusters, and then the energy barriers of intermediates are decreased as well, which enhances the OER performance. This design not only provides a simple strategy to construct amorphous structures with abundant oxygen vacancies using ionic liquid‐dopants, but also presents an in‐depth insight into the OER mechanism in alkaline solution.

well-tuned electronic configuration. [4,5] Especially, with an edge-sharing octahedral MO 6 layer-stacking crystal structure served as highly active sites, NiFe-based layered double hydroxides (NiFe LDHs) exhibited highly remarkable intrinsic electrochemical activity. [6,7] Several studies have reported that NiFe LDH is actually a precatalyst, and it heavily undergoes a self-reconstruction process in basic solution, generating Ni oxyhydroxide (NiOOH) as the active species for OER. [8,9] To begin with, Alexis et al. characterized the vibration mode of NiOOH by in situ Raman spectra, when Ni-Fe films worked as anodes in basic media during the OER. [10] Then, some research revealed that NiOOH species is generally recognized as the positive reaction species and can provide abundant intrinsic catalytic sites for OER. [11][12][13] Not limited to OER, NiOOH can also efficiently catalyze the anodic degradation of urea that featured with the more complex six-electron redox process. [14,15] However, owing to the instability of the high valence state of Ni (III) which can easily transform into Ni (II), the direct synthesis and application of NiOOH have not been realized, unless a high anodic polarization is applied. [16,17] Therefore, it is crucial to explore synthesis methods to stabilize NiOOH catalyst.Among the multiple regulation methods, surface structure reconstruction with the aid of a new phase is widely accepted as a controllable approach for synthesizing novel composites with NiOOH is considered as the most active intermediate during electrochemical oxidation reaction, however, it is hard to directly synthesize due to high oxidation energy. Herein, theoretical calculations predict that α-FeOOH enables a decline in formation energy and an improvement in stabilization of NiOOH in NiFe-based layered double hydroxide (LDH). Inspiringly, a composite composed of α-FeOOH and LDH is well-designed and successfully fabricated in hydrothermal treatment by adding extra Fe 3+ resource, and stable NiOOH is obtained by the following electro-oxidation method. Benefiting from strong electron-capturing capability of α-FeOOH, it efficiently promotes charge redistribution around the Ni/Fe sites and activates Ni atoms of LDH, verified by X-ray photoelectron spectra (XPS) and X-ray absorption spectra (XAS). The d-band center is optimized that balances the absorption and desorption energy, and thus Gibbs free energy barrier is lowered dramatically toward oxygen evolution reaction (OER) and urea oxidation reaction (UOR), and finally showing an outstanding overpotential of 195 mV and a potential of 1.35 V at 10 mA cm −2 , respectively. This study provides a novel strategy to construct highly efficient catalysts via the introduction of a new phase for complex multiple-electron reactions.

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The electronic structure of composites plays a critical role in photocatalytic conversion, whereas it is challenging to modulate the orbital for an efficient catalyst. Herein, we regulated the t 2g orbital occupancy state of Ti to realize efficient CO 2 conversion by adjusting the amount of photo-deposited Cu in the Cu/ TiO 2 composite. For the optimal sample, considerable electrons transfer from the Cu d orbital to the Ti t 2g orbital, as proven by X-ray absorption spectroscopy. The Raman spectra results also corroborate the electron enrichment on the Ti t 2g orbital. Further theoretical calculations suggested that the orbital energy of the Ti 3d orbital in TiO 2 is declined, contributing to accepting Cu 3d electrons. As a result, the Cu/TiO 2 composite exhibited an extremely high selectivity of 95.9 % for CO, and the productivity was 15.27 μmol g À 1 h À 1 , which is almost 6 times that of the original TiO 2 . Our work provides a strategy for designing efficient photocatalysis as a function of orbital regulation.

Metal−air batteries have attracted great attention because of their high energy density merits, among which zinc−air batteries (ZABs) are of great interest owing to their high energy density, intrinsic safety, and low cost. However, sluggish kinetics of the electrochemical oxygen evolution reactions and oxygen reduction reactions (OER and ORR) greatly hinder the development of ZABs. [5,6] Preparing a low-cost electrocatalyst with low overpotential and high stability is thereof a key issue. Effective synthesis methods are appealing to obtain robust catalysts. [7][8][9] Previous reports show that modifying the surface or bulk of materials by constructing composites, such as heterogeneous phase constructing, vacancy constructing, and interfacial engineering, can largely improve the performance of catalysts. [10][11][12][13] With regard to structural regulation, disrupting long-range order by constructing composite structures facilitates to obtain unexpected catalytic properties due to the synergistic coupling effect. [4,14] These methods can merely improve the performance of specific catalytic reactions, however, the method universality remains being improved.Surface modification and reconstruction are interesting topics from a viewpoint of catalysis, and many challenges Constructing composite structures is an essential approach for obtaining multiple functionalities in a single entity. Available synthesis methods of the composites need to be urgently exploited; especially in situ construction. Here, a NiS/NiFe 2 O 4 composite through a local metal−S coordination at the interface is reported, which is derived from phase reconstruction in the highly defective matrix. X-ray absorption fine structure confirms that long-range order is broken via the local metal−S coordination and, by using electron energy loss spectroscopy, the introduction of NiS/NiFe 2 O 4 interfaces during the irradiation of plasma energy is identified. Density functional theory (DFT) calculations reveal that in situ phase reconfiguration is crucial for synergistically reducing energetic barriers and accelerating reaction kinetics toward catalyzing the oxygen evolution reaction (OER). As a result; it leads to an overpotential of 230 mV @10 mA cm −2 for the OER and a half-wave potential of 0.81 V for the oxygen reduction reaction (ORR); as well as an excellent zinc−air battery (ZAB) performance with a power density of 148.5 mW cm −2 . This work provides a new compositing strategy in terms of fast phase reconstruction of bifunctional catalysts.The ORCID identification number(s) for the author(s) of this article can be found under https://doi.org/10.1002/adma.202110172.