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Mn-based Li-ion battery cathodes encompass a great variety of materials structures. Decades of research effort have proven that developing a Mn-based structure featuring a high redox activity, stable cycling, and cost-effectiveness is a longstanding challenge. Motivated by such a need and inspired by the structural diversity of Mn-based cathodes, we develop a partially cation-disordered lithium niobium manganese oxide with a zigzag structure, filling the knowledge gap between zigzag-ordered and fully disordered Li–Mn-based oxides. Electrochemically, the partially disordered cathode greatly unlocks the redox activity of the zigzag lattice and maintains the cycling stability. Mechanism-wise, the partial disordering suppresses the disproportionation reaction of Mn(III) and facilitates a disordered λ-MnO2–tetragonal cation-disordered rock salt structural transformation. The work suggests the substantial opportunity of using partial disordering as the key strategy to revive locked-up redox activities and realize new energy storage mechanisms, for the pursuit of high-performance cost-effective battery materials. 

We report a versatile method based on seed-mediated growth for the facile synthesis of trimetallic Pd@PtxAu1−x core-shell nanocubes. By simply varying the feeding ratio between the Pt(II) and Au(III) precursors, the atomic ratio of Pt to Au in the shell and thereby the ensemble state of Pt atoms on the surface can be tuned to control the binding configuration of O2 molecules. Specifically, discrete Pt atoms on the surface promote the adsorption of O2 molecules in the Pauling configuration to enhance the catalytic selectivity of the nanoparticles toward H2O2 via the two-electron oxygen reduction reaction, with the Pd@Pt0.025Au0.975 nanocubes showing selectivity as high as 91% at 0.45 VRHE. This work offers a viable means to augment the electrocatalytic performance of alloy nanocrystals by controlling their surface compositions. 

Abstract To enhance the reaction kinetics without sacrificing activity in porous materials, one potential solution is to utilize the anisotropic distribution of pores and channels besides enriching active centers at the reactive surfaces. Herein, by designing a unique distribution of oriented pores and single crystalline array structures in the presence of abundant acid sites as demonstrated in the ZSM-5 nanorod arrays grown on monoliths, both enhanced dynamics and improved capacity are exhibited simultaneously in propene capture at low temperature within a short duration. Meanwhile, the ZSM-5 array also helps mitigate the long-chain HCs and coking formation due to the enhanced diffusion of reactants in and reaction products out of the array structures. Further integrating the ZSM-5 array with Co₃O₄nanoarray enables comprehensive propene removal throughout a wider temperature range. The array structured film design could offer energy-efficient solutions to overcome both sorption and reaction kinetic restrictions in various solid porous materials for various energy and chemical transformation applications.