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2D materials have garnered considerable interest in various applications from catalysis to energy storage. However, the self‐stacking and poor air stability of 2D materials (e.g., MXene) leads to serious performance degradation, in particular, of micro‐supercapacitors (MSCs) with narrow working voltage and low energy density. Here, a universal confined interfacial assembly strategy is demonstrated for controllably synthesizing a series of 2D mesoporous heterostructures for high‐voltage and high‐energy ionogel‐based MSCs. This assembly process reveals accurate controllability and extraordinary versatility, endowing the 2D mesoporous heterostructures with highly adjustable mesopore size (7–22 nm), tunable thickness (15–29 nm), variable carbon precursors (including oligochitosan, glucose, and sucrose), and replaceable 2D substrates (e.g., MXene, graphene, BN, and MoS2). As a proof of concept, the 2D mesoporous carbon@MXene based MSCs with ionic liquid ionogel electrolyte deliver ultrahigh voltage of 3.7 V, superior areal energy density of 181.3 µWh cm−2, excellent flexibility with 99% of capacitance retention at 180°, and excellent modular self‐integration for variable voltage/capacitance output, surpassing most reported MXene based MSCs. Therefore, this work will open a novel available paradigm for scalable fabrication of 2D mesoporous materials to target high‐performance and functional microscale power source. [ABSTRACT FROM AUTHOR]

Improving the complete ethanol electrooxidation on Pd-based catalysts in alkaline media has drawn widely attention due to the high mass energy density. However, the weak adsorption energy of CH3CO* on Pd restricts the C-C bond cleavage. Inspired by the molecular orbital theory, we proposed the d-state-editing strategy to construct more unoccupied d-states of Pd for the enhanced interaction with CH3CO* to break C-C bonds. As expected, the reduced number of eg electrons and more unoccupied d-states of Pd successfully formed on as-prepared porous RhAu-PdCu nanosheets (PNSs). Theoretical calculations show that the optimized d-states of RhAu-PdCu PNS can effectively improve the adsorption of CH3CO* and drastically reduce the energy barrier of C-C bond cleavage, thus boosting the complete oxidation of ethanol. The charge ratio of C1 pathway on RhAu-PdCu PNSs is 51.5%, more than 2 times higher than that of Pd NSs. Our finding provides an innovative perspective for the design of highly-efficient noble-based electrocatalysts. [ABSTRACT FROM AUTHOR]

Fluorescent single crystals that respond to multiple external stimuli are of great interest in molecular machines, sensors, and displays. The integration of photo‐ or acid‐induced fluorescence enhancement and bending in one organic crystal, however, has not been reported yet. Herein, we report the interesting plastic photomechanical bending and switching on of the fluorescence of an azine crystal in a single‐crystal transformation, due to extended π‐conjugation and molecular slippage. Moreover, the fluorescent plastic bending driven by multiple volatile acid vapors was firstly observed, and attributed to the synergistic effect of push–pull electronic structure and hydrogen bonding. The single crystal also shows high elasticity under external force. In addition, reversible fluorescence switching can be triggered by grinding and solvent fuming, as well as by the adsorption and desorption of HCl vapor. The integration of plastic, elastic bending and switch‐on fluorescence into one single crystal provides a new strategy for next‐generation smart materials. [ABSTRACT FROM AUTHOR]

Density functional theory calculations have been carried out on ternary PtmAunAgl clusters of low nuclearity (m + n+l = 5, 6 and 7). Various properties including average bond distance, binding energy, mixing energy, ionisation potential, electron affinity, HOMO–LUMO gap and fragmental channel, are reported for the optimised structures. The variations of the calculated properties of the PtmAunAgl clusters as a function of concentrations (i.e. all m-, n-, and l-values) are displayed by ternary diagrams. The geometric, energetic and electronic properties are sensitive to the composition and size of PtmAunAgl clusters. [ABSTRACT FROM AUTHOR]

We report a theoretical investigation of neutral AuxAgyCuz and cationic AuxAgyCuz+ ternary clusters, for x + y+z = 5 and 6. Our study is performed within density functional theory at the TPSSTPSS/SDD level. The geometries, chemical order, binding energy, mixing energy, second difference in the energy, adiabatic ionisation potential of these clusters are evaluated as a function of the whole concentration range. The most probable dissociation channels and the corresponding dissociation energies for the most stable clusters are also determined and discussed. [ABSTRACT FROM AUTHOR]