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Precise construction of high-density single-atom active centers on polymeric semiconductors, together with concurrent regulation of their interfacial charge-transfer behavior, remains a central challenge for both photocatalytic energy conversion and neuromorphic electronics. Yet conventional wet photodeposition routes suffer from solvent-induced coordination distortion, defect formation, and limited metal dispersion. Here, we report a solvent-free dry-state in situ photoreduction strategy that anchors atomically dispersed Pt onto highly crystalline carbon nitride (AD-Pt-HCCN), achieving a Pt precursor conversion efficiency of 70.5%, which is 5.5 times higher than that of wet photodeposition. High-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM), X-ray photoelectron spectroscopy (XPS), and X-ray absorption fine structure (XAFS) collectively confirm uniformly distributed Pt single atoms coordinated in a quasi-fivefold configuration within triazine-heptazine frameworks. This coordination environment suppresses the formation of a classical nanoparticle-induced Schottky-type barrier and promotes ultrafast interfacial charge extraction, as supported by femtosecond transient absorption (fs-TA), photoluminescence (PL), time-resolved PL (TRPL), and electrochemical impedance spectroscopy (EIS) analyses. As a result, a photocatalytic H2 evolution rate of 5.8 mmol & centerdot;g-1 & centerdot;h-1 is achieved, outperforming the counterpart prepared by conventional wet photodeposition (3.8 mmol & centerdot;g-1 & centerdot;h-1), owing to the synergistic contributions of the increased Pt loading efficiency and the enhanced interfacial charge transfer induced by atomically dispersed Pt sites. Remarkably, the same atomic Pt sites serve as efficient charge-modulation centers in neuromorphic transistors, enabling pronounced excitatory postsynaptic current (EPSC)/inhibitory postsynaptic current (IPSC) responses, robust long-term potentiation/depression (LTP/LTD), and linear, hardware-relevant synaptic weight updates. Integrating experimentally extracted conductance states into an artificial neural network (ANN) framework yields high recognition accuracy of 98.6%, highlighting the broad potential of AD-Pt-HCCN as a multifunctional building block for energy-intelligence convergence.

Selectivity in sensitive biosensing requires avoiding multi-enzyme-like activity, but suppressing the multi-enzyme-like activity of transition metals remains challenging. Recently, planar hyper-coordinate states have led to an emerging family of 2D materials with strong planar confinement. Here, we propose a possible strategy to enhance the selectivity of biosensing using planar hyper-coordinate transition metals, and verified our strategy through simulations of the planar hyper-coordinate 2D materials ScCN₃B₆ and the non-planar 2D material YCN₃B₆ for the adsorption of biomolecules, including adenosine, ascorbic acid, and nucleobases. Breaking the planar confinement of ScCN₃B₆ leads to enhanced adsorption of analytes. In contrast, YCN₃B₆ does not show selectivity in the same systems compared with ScCN₃B₆. Therefore, whether the planar confinement is broken provides a possible route to enhance selectivity. Moreover, the arrangement and synergy of transition metal active sites improve the adsorption energy to specific molecular structures. The development of planar hyper-coordinate transition metals opens a fertile playground for highly selective label-free biosensing.

The electrocatalytic reduction of carbon dioxide (CO2) into fuels holds significant promise for addressing energy and environmental challenges, albeit hindered by constraints in conversion efficiency, production rates, and electrode stability. Metal diborides are considered as promising electrocatalysts that may demonstrate superior CO2 electroreduction performance due to their distinctive electronic properties. Herein, a series of novel bulk metal diborides, encompassing transition metals from group IVB to group VIIB elements, were fabricated using a high pressure-high temperature technique, which were directly utilized as self-supporting electrodes for electrocatalytic reduction of CO2. The zirconium diboride (ZrB2) electrode stood out in metal diborides with superior electrocatalytic activity in generating carbon monoxide (CO), achieving a Faradaic efficiency of 92.2% at-2.2 V vs. Ag/Ag+ in ionic liquid-based electrolytes. Impressively, the ZrB2 electrode demonstrated stable catalysis of CO2 reduction to CO over a nearly 60-h electrolysis period. Furthermore, the ZrB2 electrode and ionic liquid-based electrolytes could synergistically catalyze the reduction of CO2 to CO. Experimental results and density functional theory calculations support the notion that exposed metal sites on the ZrB2 (001) surface could enhance *CO desorption and restrain the hydrogen evolution reaction, thereby facilitating the conversion of CO2 into CO.<br /> (c) 2026 Published by Elsevier B.V. on behalf of Chinese Chemical Society and Institute of Materia Medica, Chinese Academy of Medical Sciences.

Catalytic conversion of lithium polysulfides (LiPSs) is a promising avenue to suppress the shuttle effect and enhance the redox kinetics of lithium–sulfur (Li–S) batteries. However, the consecutive multiple LiPSs redox reactions make the activity prediction of electrocatalysts elusive. Herein, we propose a lower Hubbard band (LHB) descriptor to regulate tandem electrocatalytic LiPSs conversion for fast and robust Li–S batteries. Combined with theoretical calculations, the catalytic activity is jointly determined by the balance between LHB center position (Ɛ_LHB) and LHB width (ꞷ_LHB). As a proof of concept, Fe₃O₄@FeP shows a balance of possessing a close Ɛ_LHB to the Fermi level and a wide ꞷ_LHB simultaneously. An accelerated tandem electrocatalytic LiPSs conversion is achieved, where a close Ɛ_LHB to Fermi level (with Fe₃O₄ as the active center) benefits the adsorption of long-chain LiPSs and catalyzes S₈-to-Li₂S₄ process, while a wide ꞷ_LHB (with FeP as the active center) subsequently contributes to catalyze the Li₂S₄-to-Li₂S reaction. Consequently, the elaborate Li–S batteries deliver outstanding cycle stability over 1000 cycles and superior rate performance over 10C. Further, the constructed Ah-scale pouch cell delivers notable energy density of 360.6 Wh kg⁻¹. This work demonstrates the great promise of LHB regulation strategy for designing high-efficient electrocatalysts for Li–S batteries and beyond.

We propose a novel phase of hydrogen-substituted Janus WS₂ using a cluster expansion approach based on the density functional theory (DFT). This method reveals that W₃SH₅ is an energetically stable structure adopting a hexagonal lattice. Going beyond the zero-Kelvin limitation of conventional DFT, we demonstrate that the W₃SH₅ phase remains dynamically stable up to 300 K, as confirmed by temperature-dependent effective potential calculations. Shedding light on the electronic properties, spin–orbit coupling (SOC) has a significant effect on the electronic structure by lifting band degeneracies, resulting in an increased density of states at the Fermi level. Moreover, the inclusion of SOC in W₃SH₅ elucidates the contribution of H orbitals, which show a pronounced accumulation near the Fermi level. Regarding hydrogen diffusion, we determined the most favorable pathways through total energy calculations. The results suggest that hydrogen atoms preferentially diffuse through subsurface channels rather than along the top of the W–S layer, indicating that off-layer diffusion is energetically more favorable.

This study introduces a time-dependent solvothermal synthesis of hydrogen-bonded melamine cyanurate and melamine diborate at 180°C, offering precise control over their framework compositions and structures through reaction time. The selective formation of melamine diborate and melamine cyanurate is achieved using the same set of precursors with cyanuric acid generated in situ from melamine hydrolysis. The phase composition varies with the reaction time, as confirmed by Fourier transformed infrared (FTIR) and X-ray photoelectron spectroscopy (XPS), which reveal the structural progression of these frameworks. Our synthesis method allows melamine cyanurate to nucleate or grow on melamine diborate crystals adopting a more crystalline rod-like morphology with clearer texture. Density functional theory (DFT) enhances the understanding of their electronic structures, highlighting core-level binding energy shifts (N 1s and B 1s) and the chemical activity of lone pair electrons, with the mixture of π and σ bonds playing a key role in determining the bandgaps. This proposed synthesis method enables precise tuning of hydrogen-bonded framework compositions providing valuable insights for material synthesis and structural design.

Rhabdophane has an outstanding capacity of accommodating radioactive nuclides and is recognized as a significant host phase for the enrichment of actinides from radioactive waste liquid. Thus, assessing the impact of impurities present in such waste streams on rhabdophane crystallization is critical. This study systematically investigates the effects of Fe3+/Fe2+ coincorporation with actinides on the precipitation behavior of rhabdophane. Some specific issues, including lattice occupation of Fe3+, precipitation reaction kinetics, crystal growth affected under the influence of trace iron, and leaching stability, are discussed in detail. The results reveal that the presence of Fe3+, rather than Fe2+, can lower the energy barrier for nucleation and accelerate the transformation of Th-rich nucleus into rhabdophane. The limited uptake of Fe3+ with a suggested substitution ratio below 1%, contributes to establishing the stability domain of the rhabdophane phase, whereas excess Fe3+ promotes the formation of the FePO4 & centerdot;2H2O phase, which synergistically enhances the grain growth kinetics of rhabdophane/monazite through an aggregation-adsorption effect. Based on density functional theory of structural energetics, Fe3+ occupation is energetically favorable at nonhydrated [LaO8] sites in rhabdophane, despite the fact that two-thirds of lattice sites are associated with [LaO8 & centerdot;H2O] sites. Intriguingly, amorphous FePO4 & centerdot;2H2O can act as active sites to facilitate the formation of a surface alteration layer with improving the leaching stability of Th4+ in pH = 5-7 solutions.

Catalytic conversion of lithium polysulfides (LiPSs) is regarded as an effective avenue to tackle the shuttle effect of lithium-sulfur (Li-S) batteries, especially based upon transition-metal oxides (TMOs). However, the activity origin and corresponding mechanistic insights into such catalytic systems remain elusive. Herein, an activated state associated with the lower Hubbard band (LHB) transition is proposed to elucidate the origin of activity of TMOs by taking Mn3O4 as a model electrocatalyst. Specifically, the broadening of LHB width, the upshift of LHB position, and the orbital rearrangement of LHB, triggered by the in situ substitution of the O atoms in Mn3O4 with the S atoms of LiPSs under working conditions, synergistically enable fast electron transfer and modulate the adsorption capability to a moderate level. Benefiting from these advantages, the Mn3O4 electrocatalyst is converted from the torpid state to the activated state for expediting LiPS conversion. Eventually, the Li-S batteries assembled with Mn3O4 deliver excellent rate performance over 6 C and outstanding cycling stability over 1000 cycles. Moreover, an Ah-scale pouch cell is constructed and delivers a notable energy density of 388.1 W h kg-1. Our work offers a promising pathway based on the regulation of LHB for designing high-performance electrocatalysts for Li-S systems and beyond.

Photocatalytic water splitting has attracted extensive attention for its bright prospects in producing clean hydrogen energy. To realize efficient solar-to-hydrogen energy conversion, it is important to explore a photocatalyst with high electron-hole separation and wide-range solar absorption. Herein, a novel twodimensional metal-hydride, LuH₃, is designed and its viability as an efficient photocatalyst for overall water splitting is evaluated in the present work. It reveals that LuH₃ monolayer is an isotropic semiconductor with a direct band gap of 2.56 eV, decreased to 1.872 eV in a bilayer, exhibiting strong absorption efficiency for ultraviolet, visible, and near-infrared regions. Besides, it has favorable valence and conduction band positions for water redox reactions of O₂/H₂O and H⁺/H₂, high carrier mobility, and significant charge separation capability due to the orientation-dependent distribution in band edges, which play vital roles to enhance photocatalytic performance. The higher partial charge densities on H_1b and H_2d in HOMO lead to amore potent oxidation reaction, facilitating the reduction reaction and the production of hydrogen. In particular, LuH3 monolayer is flexible and sensitive to external stress. Applying both isotropic and uniaxial strain has a limited impact on achieving favorable band alignments with water redox potentials, providing distinct opportunities for various applications. In both acidic and alkaline environments, LuH3 monolayer shows significant potential for efficient photocatalysis in the context of overall water splitting. Furthermore, LuH3, a van der Waals material, can exfoliate from multilayered or bulk forms with a cleavage energy of 1.07 J/m², which is three times higher than the experimentally measured 0.37 J/m² for graphite. These findings highlight the potential of LuH₃ monolayer as an efficient solar-spectrum water-splitting photocatalyst, with implications for sustainable energy conversion technologies utilizing solar energy for clean and renewable hydrogen fuel generation.

The sp²-hybridization is key to understand structures of 2D materials with light p-block elements. However, hunting for sp²-hybridized 2D materials with heavy p-block elements remains challenging due to weaker π-bonding and increased steric effects. Here we proposed design principles for 2D materials based on carbon nitride with adjacent Lewis-acidic center of group IIIA elements. We introduce a family of 2D materials XB₉C₄N₆ (X = Al, Ga, In and Tl) with high thermodynamic stability. Density functional theory (DFT) calculations reveal that XB₉C₄N₆ exhibit a polycyclic lattice with high delocalized π electrons, primarily from B₆ ring, which play the key role in the hole and electron transports. These materials exhibit small electron effective mass of ∼ 0.28 m₀, suitable bandgaps of ∼ 1.2 eV and strong light absorption peaks of violet, red and near-infrared lights, which cover the solar spectral irradiance. Notably, AlB₉C₄N₆ emerges as an environmentally friendly semiconductor for electronics and photovoltaic devices. The design principles will enrich the fundamental understanding of π-conjugated heavy p-block elements and family of sp²-hybridized 2D materials.