Pd nanocatalysts engineering for direct oxidation methane-to-methanol with 99.7% selectivity.

Pd catalysts demonstrate remarkable activity and selectivity for the direct oxidation methane-to-methanol (DOMM) under mild conditions. However, understanding the structure-performance relationship is challenging because Pd catalysts used in existing studies have complex polycrystalline structures. In this work, well-defined Pd nanocrystals with controlled morphologies are synthesized and used as model systems to investigate the origins of the observed structure-activity differences.

Simultaneous Manipulation of Electric Double Layer and Zn (100) Deposition Enabled by Anions for Highly Stable Zn Anodes.

Controlling the growth orientation of zinc (Zn) is an effective method of stabilizing Zn anodes. Although Zn (100) exhibits faster Zn electroplating/stripping kinetics than Zn (002), its high chemical reactivity results in susceptibility to water-induced side reactions. Herein, a two-pronged electrolyte engineering strategy is proposed to enhance the reversibility of Zn anodes, that is, modulating vertically oriented Zn (100) plating while simultaneously constructing a water-poor electrical double layer (EDL).

Recent Advances in Fe-Free M-N-C Catalysts for Oxygen Reduction Reaction.

Atomically dispersed metal-nitrogen-carbon (M-N-C) materials, characterized by well-defined coordination structures, have emerged as promising candidates to supersede costly platinum-based catalysts for the oxygen reduction reaction (ORR). Although Fe-N-C catalysts exhibit the highest ORR activity among Pt-free systems, their practical application is hindered by durability challenges stemming from Fenton reaction-induced degradation. Fe-free M-N-C catalysts (MCo, Mn, Ni, etc.

Self-Healing Indium Sulfide Catalyst for Efficient and Robust Electrocatalytic CO2 Conversion.

The reduction-reconstruction of the catalyst under negative bias has been identified as a significant rationale underlying the performance degradation of the electrocatalytic CO reduction reaction (CORR). Screening catalysts with stable phases and robust crystal structures appears to be a feasible approach to counteract the reduction corrosion. In this work, with the guidance of computational predictions, a tetragonal phase InS electrocatalyst is designed through a self-healing strategy for the conversion of CO to formate.

Electrically Induced Topological Chirality Switching in Orbital-Engineered Covalent Organic Radical Framework Monolayers.

Engineering the topological properties of a quantum anomalous Hall (QAH) insulator is crucial for advancing spintronics and quantum devices. Conventional methods relying on external magnetic fields face limitations in their scalability and energy efficiency. Here, we present the realization of bipolar topological magnetic semiconductor (BTMS) using two-dimensional covalent organic radical frameworks (2D CORFs) based on an orbital-engineering approach.

Oxygen-Coordinated Cr Single-Atom Catalyst for Oxygen Reduction Reaction in Proton Exchange Membrane Fuel Cells.

Carbon-supported metal single-atom catalysts (M-SACs) are promising oxygen reduction reaction (ORR) catalysts. Their ORR activity and selectivity are significantly affected by the heteroatoms that coordinate the central metal atoms. Previous reports found that oxygen-coordinated M-SACs promoted a 2e ORR rather than the 4e ORR that is more desirable for fuel cells.

Enhancing Magnetic Ordering in Two-Dimensional Metal-Organic Frameworks via Frontier Molecular Orbital Engineering.

Two-dimensional (2D) metal-organic frameworks (MOFs) have promise for use in lightweight permanent magnets in contrast to inorganic solid- or molecule-based magnets, but the realization of 2D MOF magnets with a high ordering temperature is limited by the typically weak spin exchange interactions. Here, we have proposed a frontier molecular orbital engineering strategy for modulating magnetism in 2D MOFs. It shows that the magnetic ground state can be mediated by two intra-atomic spin exchange pathways in organic ligands, akin to the Bloch and Heisenberg models, depending on the shape of the frontier orbitals of the organic ligands.

Precise Synthesis of Dual-Single-Atom Electrocatalysts through Pre-Coordination-Directed in Situ Confinement for CO Reduction.

Dual-single-atom catalysts (DSACs) are the next paradigm shift in single-atom catalysts because of the enhanced performance brought about by the synergistic effects between adjacent bimetallic pairs. However, there are few methods for synthesizing DSACs with precise bimetallic structures. Herein, a pre-coordination strategy is proposed to precisely synthesize a library of DSACs.

Rechargeable Seawater-Based Chloride-Ion Batteries Enabled by Covalent Surface Chemistry in MXenes.

Rechargeable aqueous chloride-ion batteries (ACIBs) using Cl ions as charge carriers represent a promising energy-storage technology, especially when natural seawater is introduced as the electrolyte, which can bring remarkable advantages in terms of cost-effectiveness, safety, and environmental sustainability. However, the implementation of this technology is hindered by the scarcity of electrodes capable of reversible chloride-anion storage. Here, we show that a TiCCl MXene with Cl surface terminations enables reversible Cl ion storage in aqueous electrolytes.

Biologically templated formation of Cobalt-Phosphide-Graphene hybrids with charge redistribution for efficient hydrogen evolution.

Developing highly efficient and sustainable hydrogen evolution reaction (HER) electrocatalysts is important for the practical application of emerging energy technologies. The spherical structure and phosphorus-rich properties of Chlorella can facilitate the construction of comparable transition metal phosphide electrocatalysts. Here, a microorganism template strategy is proposed to construct a cobalt-phosphide-graphene hybrid.

Heterogeneous-Structured Molybdenum Diboride as a Novel and Promising Anode for Lithium-Ion Batteries.

With the development of electric vehicles, exploiting anode materials with high capacity and fast charging capability is an urgent requirement for lithium-ion batteries (LIBs). Borophene, with the merits of high capacity, high electronic conductivity and fast diffusion kinetics, holds great potential as anode for LIBs. However, it is difficult to fabricate for the intrinsic electron-deficiency of boron atom.

Turning Nonmagnetic Two-Dimensional Molybdenum Disulfides into Room-Temperature Ferromagnets by the Synergistic Effect of Lattice Stretching and Charge Injection.

Exploring two-dimensional (2D) room-temperature magnetic materials in the field of 2D spintronics remains a formidable challenge. The vast array of nonmagnetic 2D materials provides abundant resources for exploration, but the strategy to convert them into intrinsic room-temperature magnets remains elusive. To address this challenge, we present a general strategy based on surface halogenation for the transition from nonmagnetism to intrinsic room-temperature ferromagnetism in 2D MoS based on first-principles calculations.

Two-Dimensional Transition Metal Boron Cluster Compounds (MBenes) with Strain-Independent Room-Temperature Magnetism.

Two-dimensional (2D) metal borides (MBenes) with unique electronic structures and physicochemical properties hold great promise for various applications. Given the abundance of boron clusters, we proposed employing them as structural motifs to design 2D transition metal boron cluster compounds (MBenes), an extension of MBenes. Herein, we have designed three stable MBenes (M(B), M = Mn, Fe, Co) based on B clusters and investigated their electronic and magnetic properties using first-principles calculations.

Regulating Au coverage for the direct oxidation of methane to methanol.

The direct oxidation of methane to methanol under mild conditions is challenging owing to its inadequate activity and low selectivity. A key objective is improving the selective oxidation of the first carbon-hydrogen bond of methane, while inhibiting the oxidation of the remaining carbon-hydrogen bonds to ensure high yield and selectivity of methanol. Here we design ultrathin PdAu nanosheets and revealed a volcano-type relationship between the binding strength of hydroxyl radical on the catalyst surface and catalytic performance using experimental and density functional theory results.

Heterojunction Engineering of Multinary Metal Sulfide-Based Photocatalysts for Efficient Photocatalytic Hydrogen Evolution.

Photocatalytic hydrogen evolution (PHE) via water splitting using semiconductor photocatalysts is an effective path to solve the current energy crisis and environmental pollution. Heterojunction photocatalysts, containing two or more semiconductors, exhibit better PHE rates than those with only one semiconductor owing to the altered band alignment at the interface and stronger driving force for charge separation. Traditional binary metal sulfide (BMS)-based heterojunction photocatalysts, such as CdS, MoS , and PbS, demonstrate excellent PHE performance.

Multimetallic Single-Atom Catalysts for Bifunctional Oxygen Electrocatalysis.

Multimetallic alloys have demonstrated promising performance for the application of metal-air batteries, while it remains a challenge to design multimetallic single-atom catalysts (MM-SACs). Herein, metal-CN and nitrogen-doped carbon are employed as cornerstones to synthesize MM-SACs by a general two-step method, and the inherent features of atomic dispersion and the strong electronic reciprocity between the multimetallic sites have been verified. The trimetallic FeCoZn-SACs and quatermetallic FeCoCuZn-SACs are both found to deliver superior oxygen evolution reaction and oxygen reduction reaction activity, respectively, as well as outstanding bifunctional durability.

Understanding the Bifunctional Trends of Fe-Based Binary Single-Atom Catalysts.

Binary single-atom catalysts (BSACs) have demonstrated fascinating activities compared to single atom catalysts (SACs) for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). Notably, Fe SACs is one of the most promising ORR electrocatalysts, and further revealing the synergistic effects between Fe and other 3d transition metals (M) for FeM BSACs are very important to enhance bifunctional performance. Herein, density functional theory (DFT) calculations are first adapted to demonstrate the role of various transition metals on the bifunctional activity of Fe sites, and a notable volcano relationship is established through the generally accepted adsorption free energy that ΔG for ORR, and ΔG -ΔG for OER, respectively.

Ultrathin Nitrogen-Doped Carbon Encapsulated Ni Nanoparticles for Highly Efficient Electrochemical CO Reduction and Aqueous Zn-CO Batteries.

Electrochemical CO reduction reaction (CO RR), powered by renewable electricity, has attracted great attention for producing high value-added fuels and chemicals, as well as feasibly mitigating CO emission problem. Here, this work reports a facile hard template strategy to prepare the Ni@N-C catalyst with core-shell structure, where nickel nanoparticles (Ni NPs) are encapsulated by thin nitrogen-doped carbon shells (N-C shells). The Ni@N-C catalyst has demonstrated a promising industrial current density of 236.

Synthesis of Phase Junction Cadmium Sulfide Photocatalyst under Sulfur-Rich Solution System for Efficient Photocatalytic Hydrogen Evolution.

Photocatalyst with excellent semiconductor properties is the key point to realize the efficient photocatalytic hydrogen evolution (PHE). As a representative binary metal sulfide (BMS) semiconductor, cadmium sulfide (CdS) possesses suitable bandgap of 2.4 eV and negative conduction band potential, which has a great potential to realize efficient visible-light PHE performance.

Sulfur-Coordinated Transition Metal Atom in Graphene for Electrocatalytic Nitrogen Reduction with an Electronic Descriptor.

The adjacent chemical microenvironment of single metal atoms in heterogeneous catalysis is crucial to their chemical activity for various catalytic processes. Here, based on first-principles calculations, 25 single transition metal atom catalysts coordinated to sulfur species embedded in graphene (TM-S-G-SACs) are reported for nitrogen reduction under ambient condition. It shows that nine TM-S-G-SACs (TM = Mo, Sc, Cr, V, W, Ti, Nb, Mn, and Re) are promising nitrogen reduction catalysts with an optimal potential of -0.

Two-Dimensional Quaternary Transition Metal Sulfide CrMoAS (A = C, Si, or Ge): A Bipolar Antiferromagnetic Semiconductor with a High Néel Temperature.

Bipolar antiferromagnetic semiconductors (BAFSs) make up a class of spintronic materials, holding great promise for the manipulation of spin-polarized currents simply upon application of a voltage gate, but only a few two-dimensional (2D) BAFSs with a high Néel temperature () have been reported. Here, we report a family of magnetic quaternary MM'AS (M = V, Cr, Mn, or Fe; M' = Nb, Mo, Tc, or Ru; A = C, Si, Ge, or Sn) nanosheets by isovalent alloying layered transitional metal trisulfides (MAS) based on first-principles calculations. Our results show that 2D CrMoAS (A = C, Si, or Ge) nanosheets are BAFSs with band gaps ranging from 1.

Ruthenium Complex of sp Carbon-Conjugated Covalent Organic Frameworks as an Efficient Electrocatalyst for Hydrogen Evolution.

It is still a great challenge to explore hydrogen evolution reaction (HER) electrocatalysts with both lower overpotential and higher stability in acidic electrolytes. In this work, an efficient HER catalyst, Ru@COF-1, is prepared by complexation of triazine-cored sp carbon-conjugated covalent organic frameworks (COFs) with ruthenium ion. Ru@COF-1 possesses high crystallinity and porosity, which are beneficial for electrocatalysis.

Enhanced Curie Temperature of Two-Dimensional Cr(II) Aromatic Heterocyclic Metal-Organic Framework Magnets via Strengthened Orbital Hybridization.

Two-dimensional (2D) metal-organic frameworks (MOFs) with room-temperature magnetism are highly desirable but challenging due to the weak superexchange interaction between metal atoms. For this purpose, strengthening the hybridization between metal ion and organic linkage presents an experiment-feasible chemical solution to enhance the Curie temperature. Here, we report three 2D Cr(II) aromatic heterocyclic MOF magnets with enhanced Curie temperature by bridging Cr(II) ions with pyrazine, 1,4-diphosphinine, and 1,4-diarsenin linkers, i.