Zhiwen Zhuo

Beyond the geometric planarity of graphene and the outward bulging of fullerenes, a carbon sheet with negative Gaussian curvature (NGC), an “inside-out” saddle world, remains a tantalizing blind spot. A novel 2D carbon allotrope, NGC-C40, is developed through a topological engineering strategy via first-principles calculations. It displays pronounced intrinsic NGC features, lattice dynamical and thermal stability, and rare closed nodal-line semimetal characteristics. Mechanically, NGC-C40 exhibits pronounced anisotropy and a robust auxetic response, with a Poisson’s ratio ranging from −0.254 to +0.041. More importantly, it shows an unusual strain-polarity- and orientation-coupled Poisson’s ratio sign-switching behavior, arising from the cooperative response of the C8C5 skeleton and C4 region. For potassium-ion storage, NGC-C40 has a high theoretical capacity of 1116 mAh g–1, far exceeding the capacity of 223 mAh g–1 obtained for both Li and Na. It also exhibits a low K-ion migration barrier of 0.215 eV, operating voltages ranging from 1.124 to 0.031 V, and a maximum carbon-framework geometric volume expansion of 5.66%, enabled by its NGC architecture. Demonstrating multifunctional capability, NGC-C40 suggests a potential strategy for multifunctional 2D carbon design: negative Gaussian curvature may serve as an underexplored geometric factor.

Rigid azo-linked 2D azoenes exhibit node-programmable electronic structures and bonding characteristics, auxetic behavior arising from node rotation and chain angularization, and theoretical Li-ion cathode performance of 3.54 V and 855 Wh kg ⁻¹ .

A crystal facet‐guided photocarrier decoupling mechanism has been identified in strontium tantalum oxynitride (SrTaO ₂ N), representing a critical determinant for unlocking its intrinsic photocatalytic overall water splitting (POWS) capability. Single‐crystalline SrTaO ₂ N particles with low defect density and well‐defined {202} and {001}/{110} crystal facets were successfully synthesized via a charge‐compensated, molten salt‐assisted nitridation strategy. Combined experimental and theoretical investigations confirm that this distinctive facet architecture generates an intrinsic internal electric field within the crystals, which efficiently directs the separation and unidirectional migration of photocarriers toward spatially resolved crystal facets, laying a robust foundation for the POWS performance. Upon the selective deposition of RhCrO _x (H ₂ ‐evolution cocatalyst) and CoOOH (O ₂ ‐evolution cocatalyst) onto the corresponding crystal facets, SrTaO ₂ N can stably drive POWS under both visible‐light (λ ≥ 420 nm) and simulated sunlight (AM1.5G) illumination, achieving stoichiometric H ₂ and O ₂ evolution (2:1 molar ratio). This study provides fundamental mechanistic insights into the structure‐activity relationship governing POWS over SrTaO ₂ N, offering a rational materials‐design framework for the development of high‐performance photocatalysts toward efficient solar‐to‐hydrogen conversion.

The sustainable synthesis on ammonia at mild thermal conditions is a pivotal goal in catalysis, yet finding efficient alternatives to the energy-intensive Haber-Bosch process remains a great challenge. Here we show that a composite material comprising uranium and few-layer graphdiyne (U/GDY) catalyzes ammonia production with high efficiency at low temperature and pressure. We synthesize few-layer GDY in supercritical CO₂ to create a stable scaffold that hosts uranium in specific valency and cluster states. Both experimental results and theoretical calculations reveal that the unique electronic interplay between the 5 f electrons of uranium and the conjugated structure of GDY optimizes the adsorption and activation of nitrogen. This synergism facilitates a favorable reaction pathway involving specific nitrogen recognition and efficient product release. Our findings demonstrate the potential of uranium-based composites in catalysis and offer a strategy for designing actinide-carbon hybrid materials in challenging chemical transformations.

Searching for new 2D materials with novel structure, bonding, and properties is attractive and challenging over time. Through comprehensive global structure searching, the most thermodynamically stable configuration of the beryllium nitride monolayer (α-2D-Be₃N₂) is identified. α-2D-Be₃N₂ monolayer has peculiar Be bonding behavior with multicenters-like and ionic bonding characters, including the strong Be-N interactions "few residual electrons gathered infinite centers bond" with high coordinated numbers of N and Be in its semiplanar structure. Structural analyses confirm the monolayer's dynamic stability and outstanding thermal stability with a reversible crystalline-amorphous phase transition. Electronic structure calculations reveal an indirect bandgap of 5.09 eV, accompanied by intense deep-UV optical absorption. The material also exhibits anomalous mechanical properties with purely in-plane negative Poisson's ratios from -0.080 to -0.193, and excellent halide ion conduction ability with low barrier energy (only 0.20 eV for Cl ions). Therefore, the α-2D-Be₃N₂ monolayer is a promising multifunctional material for applications, such as insulators, deep-UV detectors, auxetic materials, reversible crystalline-amorphous materials, temperature-controlled information storage, iontronic devices, and solid halide ion conductors.

Photocatalytic oxygen reduction reaction (ORR) represents a green and cost-effective means to produce the high-value industrial compound H₂O₂. However, the efficient H₂O₂ synthesis awaits in-depth knowledge of the ORR mechanisms for the design of highly active photocatalysts. In this work, surface indium vacancies (denote hereafter as V_In) have been introduced into In₂S₃, which significantly boosts the photocatalytic activity for H₂O₂ production, with an optimal H₂O₂ generation rate of 4.77 ± 0.05 mmol·h^-1·g_cat.^-1 under visible light illumination (λ ≥ 420 nm) and an apparent quantum efficiency (AQE) of 7.49 ± 0.01% at 420 ± 20 nm. Mechanistic analysis reveals the multifunctionality of V_In, such as enlarging the chemisorption capacity of O₂, enriching photo-generated electrons for ORR, endorsing high reducing power to photo-generated electrons, and promoting H₂O₂ desorption. These findings justify that surface cation vacancies open up new possibilities for H₂O₂ photosynthesis by leveraging their reaction dimensions in ORR.

Both electron and ion transports determine the dynamics of the cathode in all solid–state lithium metal batteries (ASSLMBs). Traditional composite strategies combining solid electrolytes and electronic conductors cause complex solid-state interfaces that hinder carrier migration. We present a high-entropy mixed ionic and electronic conductor (HE-O-MIEC), Li _1/6-x (LaPrNdSrBa) _1/6 CoO _3-δ , based on oxidation-resistant electronic conductors. HE-O-MIEC exhibits an electronic conductivity of 1150 siemens per centimeter and a Li ⁺ conductivity of 2.3 × 10 ⁻⁴ siemens per centimeter at room temperature. The enhanced Li ⁺ conductivity is attributed to the large configurational entropy, promoting multicomponent solubility and increased Li ⁺ concentration. HE-O-MIEC exhibits electrochemical and thermodynamic compatibility with LiCoO ₂ and stabilizes ion/electron transport in the ASSLMB using the Li _6.4 La ₃ Zr _1.4 Ta _0.6 O ₁₂ electrolyte. Without organic electrolyte or additional pressure, the ASSLMB achieves 115–milliampere·hours per gram initial discharge capacity at 30°C and retains 83% capacity after 500 cycles. Homogeneous electron and ion transport in the HE-O-MIEC demonstrates potential to improve active material utilization and address interfacial challenges in ceramic-based ASSLMBs.

Sodium-sulfur (Na-S) batteries hold significant promise for next-generation energy storage devices due to their high theoretical energy density and environmental friendliness. However, the practical applications are impeded by the polysulfide shuttle effect and sluggish redox kinetics. In this work, we explore the two-dimensional (2D) γ-phase group IV monochalcogenides (γ-MX, M = Ge, Sn; X = S, Se) as potential anchoring materials in Na-S batteries to solve the above issues based on first-principles calculations. The results show that these γ-MX monolayers have moderate adsorption energies toward both S₈ and sodium polysulfides (NaPSs), which are conducive to mitigating the dissolution and shuttle effect of NaPSs. Notably, the γ-MX monolayers, particularly γ-GeS and γ-SnS, exhibit relatively low Gibbs free energy changes for the sulfur reduction reaction (SRR), as well as the energy barriers for Na₂S decomposition, ensuring a fast charge/discharge rate and high sulfur utilization in Na-S batteries. Furthermore, the performance of γ-GeS and γ-SnS monolayers as anchoring materials in Na-S batteries can be further enhanced by applying biaxial strain. Our findings indicate that the 2D γ-phase group IV monochalcogenides possess significant potential for applications in Na-S batteries.

Alkali metal anodes (Li, Na, and K) hold great promise for energy storage due to their high specific capacities and low reduction potentials. However, the deposition of alkali metals is frequently disrupted by a simultaneous desolvation process, leading to dendrite growth and rapid capacity decay. In this work, we present a general strategy to achieve dendrite-free, high-capacity alkali metal batteries by utilizing the two-dimensional (2D) confinement of desolvated ions. 2D transition metal disulfides (TMDSs) are employed as interlayers with high adsorption energy for alkali metal ions, effectively facilitating the rapid separation of the desolvation process from metal deposition. The desolvated ions, characterized by high diffusivity, are confined within the 2D channels of TMDSs, enabling planar alkali metal deposition without interference from the desolvation process. Furthermore, the TMDS interlayers avoid side reactions between solvents and metals during deposition, resulting in a thin solid electrolyte interphase that promotes fast ion diffusion. This approach enables dendrite-free K metal batteries capable of plating/stripping at 10 mAh cm^-2 and cycling at 36 C for over 3000 cycles. Our strategy provides a novel pathway to advance high-energy metal batteries, significantly enhancing their performance and longevity.