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In aqueous aluminum‐ion batteries (AAIBs), the insertion/extraction chemistry of Al3+ often leads to poor kinetics, whereas the rapid diffusion kinetics of hydronium ions (H3O+) may offer the solution. However, the presence of considerable Al3+ in the electrolyte hinders the insertion reaction of H3O+. Herein, we report how oxygen‐deficient α‐MoO3 nanosheets unlock selective H3O+ insertion in a mild aluminum‐ion electrolyte. The abundant oxygen defects impede the insertion of Al3+ due to excessively strong adsorption, while allowing H3O+ to be inserted/diffused through the Grotthuss proton conduction mechanism. This research advances our understanding of the mechanism behind selective H3O+ insertion in mild electrolytes. [ABSTRACT FROM AUTHOR]

Understanding the correlation between the structural evolution of electrocatalysts and their catalytic activity is both essential and challenging. In this study, we investigate this correlation in the context of the oxygen evolution reaction (OER) by examining the influence of structural disorder during and after dynamic structural evolution on the OER activity of Fe−Ni (oxy)hydroxide catalysts using operando X‐ray absorption spectroscopy, alongside other experiments and theoretical calculations. The Debye–Waller factors obtained from extended X‐ray absorption fine structure analyses reflect the degree of structural disorder and exhibit a robust correlation with the intrinsic OER activities of the electrocatalysts. The enhanced OER activity of in situ‐generated metal (oxy)hydroxides derived from different pre‐catalysts is linked to increased structural disorder, offering a promising approach for designing efficient OER electrocatalysts. This strategy may inspire similar investigations in related electrocatalytic energy‐conversion systems. [ABSTRACT FROM AUTHOR]

Compensating the irreversible loss of limited active lithium (Li) is essentially important for improving the energy‐density and cycle‐life of practical Li‐ion battery full‐cell, especially after employing high‐capacity but low initial coulombic efficiency anode candidates. Introducing prelithiation agent can provide additional Li source for such compensation. Herein, we precisely implant trace Co (extracted from transition metal oxide) into the Li site of Li2O, obtaining (Li0.66Co0.11□0.23)2O (CLO) cathode prelithiation agent. The synergistic formation of Li vacancies and Co‐derived catalysis efficiently enhance the inherent conductivity and weaken the Li−O interaction of Li2O, which facilitates its anionic oxidation to peroxo/superoxo species and gaseous O2, achieving 1642.7 mAh/g~Li2O prelithiation capacity (≈980 mAh/g for prelithiation agent). Coupled 6.5 wt % CLO‐based prelithiation agent with LiCoO2 cathode, substantial additional Li source stored within CLO is efficiently released to compensate the Li consumption on the SiO/C anode, achieving 270 Wh/kg pouch‐type full‐cell with 92 % capacity retention after 1000 cycles. [ABSTRACT FROM AUTHOR]

Carbonylation of ethanol with CO2 as carbonyl source into value‐added esters is of considerable significance and interest, while remains of great challenge due to the harsh conditions for activation of inert CO2 in that the harsh conditions result in undesired activation of α‐C−H and even cleavage of C−C bond in ethanol to deteriorate the specific activation of O−H bond. Herein, we propose a photo‐thermal cooperative strategy for carbonylation of ethanol with CO2, in which CO2 is activated to reactive CO via photo‐catalysis with the assistance of *H from thermally‐catalyzed dissociation of alcoholic O−H bond. To achieve this proposal, an interfacial site and oxygen vacancy both abundant SrTiCuO3‐x supported Cu2O (Cu2O‐SrTiCuO3‐x) has been designed. A production of up to 320 μmol g−1 h−1 for ethyl formate with a selectivity of 85.6 % to targeted alcoholic O−H activation has been afforded in photo‐thermal assisted gas‐solid process under 3.29 W cm−1 of UV/Vis light irradiation (144 °C) and 0.2 MPa CO2. In the photo‐driven activation of CO2 and following carbonylation, CO2 activation energy decreases to 12.6 kJ mol−1, and the cleavage of alcoholic α‐C−H bond has been suppressed. [ABSTRACT FROM AUTHOR]

Single atom alloy (SAA) catalysts have been recently explored for promotion of various heterogeneous catalysis, but it remains unexplored for selective electrocatalytic reduction of carbon dioxide (CO2) into multi‐carbon (C2+) products involving C−C coupling. Herein we report a single‐atomic Bi decorated Cu alloy (denoted as BiCu‐SAA) electrocatalyst that could effectively modulate selectivity of CO2 reduction into C2+ products instead of previous C1 ones. The BiCu‐SAA catalyst exhibits remarkably superior selectivity of C2+ products with optimal Faradaic efficiency (FE) of 73.4 % compared to the pure copper nanoparticle or Bi nanoparticles‐decorated Cu nanocomposites, and its structure and performance can be well maintained at current density of 400 mA cm−2 under the flow cell system. Based on our in situ characterizations and density functional theory calculations, the BiCu‐SAA is found to favor the activation of CO2 and subsequent C−C coupling during the electrocatalytic reaction, as should be responsible for its extraordinary C2+ selectivity. [ABSTRACT FROM AUTHOR]

To achieve practical application of fuel cell, it is vital to develop highly efficient and durable Pt‐free catalysts. Herein, we prepare atomically dispersed ZnNC catalysts with Zn‐Pyrrolic‐N4 moieties and abundant mesoporous structure. The ZnNC‐based anion‐exchange membrane fuel cell (AEMFC) presents an ultrahigh peak power density of 1.63 and 0.83 W cm−2 in H2‐O2 and H2‐air (CO2‐free), and also exhibits long‐term stability with more than 120 and 100 h for H2‐air (CO2‐free) and H2‐O2, respectively. Density functional calculations further unveil that the Zn‐Pyrrolic‐N4 structure is the origin of high activity of as‐synthesized ZnNC catalyst, while the Zn‐Pyridinic‐N4 moiety is inactive for oxygen reduction reaction (ORR), which successfully explain the puzzle why most Zn‐metal‐organic framework ‐derived ZnNC catalysts in previous reports did not present good ORR activity because of their Zn‐Pyridinic‐N4 moieties. This work offers a new route for speeding up development of AEMFCs. [ABSTRACT FROM AUTHOR]

Fine‐tuning single‐atom catalysts (SACs) to surpass their activity limit remains challenging at their atomic scale. Herein, we exploit p‐type semiconducting character of SACs having a metal center coordinated to nitrogen donors (MeNx) and rectify their local charge density by an n‐type semiconductor support. With iron phthalocyanine (FePc) as a model SAC, introducing an n‐type gallium monosulfide that features a low work function generates a space‐charged region across the junction interface, and causes distortion of the FeN4 moiety and spin‐state transition in the FeII center. This catalyst shows an over two‐fold higher specific oxygen‐reduction activity than that of pristine FePc. We further employ three other n‐type metal chalcogenides of varying work function as supports, and discover a linear correlation between the activities of the supported FeN4 and the rectification degrees, which clearly indicates that SACs can be continuously tuned by this rectification strategy. [ABSTRACT FROM AUTHOR]

Accelerating slow water dissociation kinetics is key to boosting the hydrogen evolution reaction (HER) in alkaline media. We report the synthesis of atomically dispersed MoOx species anchored on Rh metallene using a one‐pot solvothermal method. The resulting structures expose the oxide‐metal interfaces to the maximum extent. This leads to a MoOx‐Rh catalyst with ultrahigh alkaline HER activity. We obtained a mass activity of 2.32 A mgRh−1 at an overpotential of 50 mV, which is 11.8 times higher than that of commercial Pt/C and surpasses the previously reported Rh‐based electrocatalysts. First‐principles calculations demonstrate that the interface between MoOx and Rh is the active center for alkaline HER. The MoOx sites preferentially adsorb and dissociate water molecules, and adjacent Rh sites adsorb the generated atomic hydrogen for efficient H2 evolution. Our findings illustrate the potential of atomic interface engineering strategies in electrocatalysis. [ABSTRACT FROM AUTHOR]

A selective shift in energy storage mechanisms is demonstrated by Wei Zhang, Weitao Zheng et al. in their Communication (e202405592). By meticulously engineering the oxygen vacancies within the α‐MoO3 structure, the selective insertion of H3O+ ions (blue droplets) in aqueous aluminum‐ion batteries is enabled...By Chengxiang Huang; Zhou Jiang; Fuxi Liu; Wenwen Li; Qing Liang; Zhenzhen Zhao; Xin Ge; Kexin Song; Lirong Zheng; Xinyan Zhou; Sifan Qiao; Wei Zhang and Weitao ZhengReported by Author; Author; Author; Author; Author; Author; Author; Author; Author; Author; Author; Author; Author [Extracted from the article]

The development of highly active single‐atom catalysts (SACs) and identifying their intrinsic active sites in oxidizing industrial hazardous hydrocarbons are challenging prospects. Tuning the electronic metal‐support interactions (EMSIs) is valid for modulating the catalytic performance of SACs. We propose that the modulation of the EMSIs in a Pt1−CuO SAC significantly promotes the activity of the catalyst in acetone oxidation. The EMSIs promote charge redistribution through the unified Pt−O−Cu moieties, which modulates the d‐band structure of atomic Pt sites, and strengthens the adsorption and activation of reactants. The positively charged Pt atoms are superior for activating acetone at low temperatures, and the stretched Cu−O bonds facilitate the activation of lattice oxygen atoms to participate in subsequent oxidation. We believe that this work will guide researchers to engineer efficient SACs for application in hydrocarbon oxidation reactions. [ABSTRACT FROM AUTHOR]

Electrochemical conversion of CO2 to valuable fuels is appealing for CO2 fixation and energy storage. The Cu‐based catalysts feature unique superiorities, but achieving high ethylene selectivity is still restricted. In this study, we propose the anchoring of an ionic liquid (IL) on a Cu electrocatalyst for improving the electrochemical CO2 reduction to ethylene. In a water‐based electrolyte and a commonly used H‐type cell, a high ethylene Faradaic efficiency of 77.3 % was achieved at −1.49 V (vs. RHE). Experimental and theoretical studies reveal that an IL can modify the electronic structure of a Cu catalyst through its interaction with Cu, making it more conducive to *CO dimerization for ethylene formation. [ABSTRACT FROM AUTHOR]

Using renewable electricity to drive CO2 electroreduction is an attractive way to achieve carbon‐neutral energy cycle and produce value‐added chemicals and fuels. As an important platform molecule and clean fuel, methanol requires 6‐electron transfer in the process of CO2 reduction. Currently, CO2 electroreduction to methanol suffers from poor efficiency and low selectivity. Herein, we report the first work to design atomically dispersed Sn site anchored on defective CuO catalysts for CO2 electroreduction to methanol. It exhibits high methanol Faradaic efficiency (FE) of 88.6 % with a current density of 67.0 mA cm−2 and remarkable stability in a H‐cell, which is the highest FE(methanol) with such high current density compared with the results reported to date. The atomic Sn site, adjacent oxygen vacancy and CuO support cooperate very well, leading to higher double‐layer capacitance, larger CO2 adsorption capacity and lower interfacial charge transfer resistance. Operando experiments and density functional theory calculations demonstrate that the catalyst is beneficial for CO2 activation via decreasing the energy barrier of *COOH dissociation to form *CO. The obtained key intermediate *CO is then bound to the Cu species for further reduction, leading to high selectivity toward methanol. [ABSTRACT FROM AUTHOR]

Fundamental understanding of the dependence between the structure and composition on the electrochemical CO2 reduction reaction (CO2RR) would guide the rational design of highly efficient and selective electrocatalysts. A major impediment to the deep reduction CO2 to multi‐carbon products is the complexity of carbon–carbon bond coupling. The chemically well‐defined catalysts with atomically dispersed dual‐metal sites are required for these C−C coupling involved processes. Here, we developed a catalyst (BIF‐102NSs) that features Cl− bridged dimer copper (Cu2) units, which delivers high catalytic activity and selectivity for C2H4. Mechanistic investigation verifies that neighboring Cu monomers not only perform as regulator for varying the reaction barrier, but also afford distinct reaction paths compared with isolated monomers, resulting in greatly improved electroreduction performance for CO2. [ABSTRACT FROM AUTHOR]

Efficient coupling solar energy conversion and N2 fixation by photocatalysis has been shown promising potentials. However, the unsatisfied yield rate of NH3 curbs its forward application. Defective typical perovskite, BaTiO3, shows remarkable activity under an applied magnetic field for photocatalytic N2 fixation with an NH3 yield rate exceeding 1.93 mg L−1 h−1. Through steered surface spin states and oxygen vacancies, the electromagnetic synergistic effect between the internal electric field and an external magnetic field is stimulated. X‐ray absorption spectroscopy and density functional theory calculations reveal the regulation of electronic and magnetic properties through manipulation of oxygen vacancies and inducement of Lorentz force and spin selectivity effect. The electromagnetic effect suppresses the recombination of photoexcited carriers in semiconducting nanomaterials, which acts synergistically to promote N2 adsorption and activation while facilitating fast charge separation under UV‐vis irradiation. [ABSTRACT FROM AUTHOR]