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Introduced orthorhombic and trigonal system into 0.5La 0.6 Sr 0.4 MnO 3 -0.5LaMn 0.6 Co 0.4 O 3 (LSMCO) by selectively incorporating Sr and Co cations into the LaMnO 3 framework during the sol-gel process, which is used to explore the relationship among crystal structure, electronic states and catalytic performance. [Display omitted] Sculpting crystal configurations can vastly affect the charge and orbital states of electrocatalysts, fundamentally determining the catalytic activity of lithium-oxygen (Li–O 2) batteries. However, the crucial role of crystal configurations in determining the electronic states has usually been neglected and needs to be further examined. Herein, we introduce orthorhombic and trigonal system into 0.5La 0.6 Sr 0.4 MnO 3 -0.5LaMn 0.6 Co 0.4 O 3 (LSMCO) by selectively incorporating Sr and Co cations into the LaMnO 3 framework during the sol-gel process, which is used to explore the relationship among crystal structure, electronic states and catalytic performance. Based on both experimental and theoretical calculations, the dual-crystal configurations induce strong lattice distortion, which promotes MnO 6 octahedra vibration and shortened Mn O bonds. Furthermore, the suppressed Jahn-Teller distortion weakens the orbital arrangement and accelerates the charge delocalization, leading to the conversion of Mn3+ to Mn4+ and optimized electronic states. Ultimately, this resulted in optimized Mn 3d and O 2p orbital hybridization and activated lattice oxygen function, leading to a significant improvement in electrocatalytic activity. The LSMCO catalyzed Li–O 2 battery achieves enhanced discharge capacity of 14498.7 mAh/g and cycling stability of 258 cycles. This work highlights the significance of inner structure and presents a feasible strategy for engineering crystal configurations to boost electrocatalysis of Li–O 2 batteries. [ABSTRACT FROM AUTHOR]

The upper shift of the d-band level of Fe active sites was realized by regulating electronic structure of NiFe 2 O 4 /MoS 2 heterostructure, fundamentally improving the electrocatalytic performance of NiFe 2 O 4 /MoS 2. [Display omitted] The electronic structure of cathode catalysts dominates the electrochemistry reaction kinetics in lithium-oxygen batteries. However, conventional catalysts perform inferior intrinsic activity due to the low d-band level of the active sites makes it difficult to bond with the reaction intermediates, which results in poor electrochemical performance of lithium-oxygen batteries. Herein, NiFe 2 O 4 /MoS 2 heterostructures are elaborately constructed to reach an electronic state balance for the active sites, which realizes the upper shift of the d-band level and enhanced adsorption of intermediates. Density functional theory calculation suggests that the d-band center of Fe active sites on the heterostructure moves toward the Fermi level, demonstrating the heterointerface engineering endows Fe active sites with high d-band level by the transfer and balance of electron. As a proof of concept, lithium-oxygen battery catalyzed by NiFe 2 O 4 /MoS 2 exhibits a large specific capacity of 21526 mA h g−1 and an extended cycle performance for 268 cycles. Moreover, NiFe 2 O 4 /MoS 2 with strong adsorption to intermediates promotes the uniform growth of discharge products, which is favor of the reversible decomposition during cycling. This work presents the energy band regulation of the active sites in heterostructure catalysts has great feasibility for enhancing catalytic activities. [ABSTRACT FROM AUTHOR]

Efficient CO 2 electrodes require optimized catalytic activity and a delicate electrode structure. However, it is often insufficient to consider only a single factor when constructing a high-performance electrode. In this study, we elaborately prepare the freestanding Fe-doped CoP catalysts on N-doped carbon cloth (Fe-CoP@N-CC) substrates, which synergistically realizes electronic structure tuning of the catalysts and electrode structure modification. The experimental and theoretical calculations reveal that the electrode structure, consisting of fully covered nanowires on an N-CC skeleton, promotes mass transfer and accommodates products. The introduction of N atoms in Fe-CoP@N-CC leads to increased defects and strong Co–N–C bonds at the interface, enhancing interfacial electron transfer. Furthermore, Fe doping optimizes the electronic structure of Fe-CoP@N-CC. This synergistic enhancement facilitates the kinetics of both CO 2 reduction reaction (CO 2 RR) and CO 2 evolution reaction (CO 2 ER), resulting in the formation of large-size spherical morphologies following the solution pathway. The improved electrocatalytic performance of Fe-CoP@N-CC electrodes was demonstrated by their high discharge capacity of 4127 mAh g−1 and cycling stability of 446 h in Li–CO 2 batteries. These findings emphasize the significance of compatibility between electrode structure and catalytic activity in the design of CO 2 electrode. • Fe-doped CoP on N-doped carbon cloth (Fe-CoP@N-CC) substrates were fabricated. • Enlarged reaction active area and promoted mass transfer. • Strong Co–N–C bonds at the interface can facilitate interfacial electron transfer. • Enhanced CO 2 RR and CO 2 ER kinetics are realized. • Optimizing morphology and discharge product pathways. [ABSTRACT FROM AUTHOR]

[Display omitted] • UMMT coating promotes the Zn2+ diffusion by the strong attraction of −C=O and −NH 2. • UMMT coating serves as a desolvation layer, mitigating the parasitic reactions. • The hydrogen bonding between urea and MMT strengthens MMT's mechanical properties. • The symmetric cell with UMMT@Zn anode survives over 1300 h at 6 mA cm−2 / 3 mAh cm−2. Clay minerals as artificial solid electrolyte interphase (SEI) layers have played a crucial role in protecting zinc metal anodes for aqueous Zn-ion batteries (AZIBs) due to their unique layered structure, negatively charged lamellas, ion exchange ability, and electronic insulation. However, the clay mineral layers exhibit limited ability to suppress dendrites and side reactions on the Zn anode in the water-based working environment. This limitation is attributed to the severe volumetric expansion, poor mechanical performance, and inferior zinc ion conductivity. To address these issues, montmorillonite (MMT) is intercalated with urea in this study. The resulting dense and robust UMMT coating layer enhances the diffusion of Zn2+ and increases the Zn2+ concentration at the Zn deposition surface through strong absorption of Zn2+ at −C=O and −NH 2 active sites. As a result, it facilitates the uniform deposition of Zn2+ and inhibits dendrite growth. Additionally, the UMMT coating layer acts as a desolvation layer, mitigating parasitic reactions originated from active water. Consequently, the UMMT coating layer enables stable Zn plating/stripping compared to MMT layer. In symmetric cells, MMT@Zn electrode exhibits a significantly longer lifespan of over 1300 h at 6 mA cm−2 with a capacity of 3 mAh cm−2. Furthermore, it demonstrates enhanced cyclic performance of 254 mAh g−1 at 10 A g−1 after 4000 cycles in Zn//V 2 O 5 full cells. This present work presents a strategy to intercalate small-molecule organics into clay minerals, enhancing their protective capacity and expanding their application as SEI layers in AZIBs. [ABSTRACT FROM AUTHOR]

Electrochemical collision technique has emerged as a powerful approach to detect the intrinsic properties of single entities. The diffusion model, together with migration and convection processes are generally used to describe the transport and collision processes of single entities. However, things become more complicated concerning microbes because of their relatively large size, inherent motility and biological activities. In this work, the electrochemical collision behaviors of four different microorganisms: Escherichia coli (Gram-negative bacteria), Staphylococcus aureus , Bacillus subtilis (Gram-positive bacteria) and Saccharomyces cerevisiae (fungus) were systematically detected and compared using a blocking strategy. By using K 4 Fe(CN) 6 as redox probe, the downwards step-like signals were recorded in the collision process of all the three bacteria, whereas the collision of S. cerevisiae was rarely detected. To further investigate the underlying reason for the abnormal collision behavior of S. cerevisiae , the effect of cell settlement was discussed. The results indicated that ellipsoidal S. cerevisiae with a cell size larger than 2 μm exhibited a cell sedimentation rate of 261.759 nm s−1, which is dozens of times higher than the other three bacteria. By further enhanced convection near the microelectrode or positioned the microelectrode at the bottom of electrochemical cell, the collision signals of S. cerevisiae were successfully detected, indicating cell sedimentation is a nonnegligible force in large cell transport. This study fully addressed the effect of cell settlement on the transport of microbial cells and provided two strategies to counteract this effect, which benefit for the deeper understanding and further application of electrochemical collision technique in single-cell detection. [Display omitted] • The electrochemical collisions of single gram-negative bacteria, gram-positive bacteria and fungi were successfully realized. • The effect of cell settlement was discussed for the first time in single-microbe collision. • Influence of diffusion, migration, convection and biological activity on cell transport towards UME was discussed. • Effect of cell settlement was counteracted by removing the supporting electrolyte and utilized in S. cerevisiae collision. [ABSTRACT FROM AUTHOR]

• An amorphous lanthanum-nickel-iron based oxide/hydroxide (a-LNFO). • XAFS confirmed the edge- and face-shared octahedra in a-LNFO. • Randomly arranged terminal and bridging forms expose active sites. • Introducing Ni3+ is benefit to the favorable covalency of metal-oxygen bond. • The a-LNFO based Li-O 2 battery shows excellent electrochemical performance. Constructing well-designed catalysts by manipulating geometrical and electrical structures is regarded as effective strategies for high-performance lithium-oxygen chemistry. However, the high activity and stability of catalysts cannot be always realized simultaneously, which is apt to result in high overpotentials and poor cycling life. Herein, we elaborately construct an amorphous lanthanum-nickel-iron based oxide/hydroxide (a-LNFO) with mixed geometrical configurations of edge- and face-shared octahedra, which exhibits decent catalytic activity and excellent stability. The disordered structure endows randomly arranged terminal and bridging forms and ample oxygen vacancies, exposing massive active sites. Besides, the introduction of Ni3+ with e g orbital occupancy of 1 benefits to the favorable covalency of metal–oxygen bond, which results in the accelerated electron transport and appropriate bond strength between the catalyst and oxygen–containing intermediates, boosting the intrinsic activities toward oxygen evolution reaction and oxygen reduction reaction. Confirmed by X-ray absorption fine structure, short distance between distorted octahedra centers (Ni and Fe cations) reduces the reaction paths and induces strong electrostatic interactions, efficiently accelerating the reaction kinetics. Simultaneously, increased couples of metal-oxygen bonds in edge- and face-shared octahedra ensure the splendid stability. As a proof of concept, the a-LNFO catalyzed lithium-oxygen battery achieves a high specific discharge capacity of 13,617 mAh/g and superior cycling stability of 435 cycles. This work reveals the positive effect of geometrical configuration transformation from corner-shared octahedra to edge- and face-shared octahedra, which provides a feasible strategy for activating oxygen electrode reactions. [ABSTRACT FROM AUTHOR]