High thermal conductivity (κ) is critical for the thermal management of nanoelectronics, as efficient heat dissipation underpins device stability and performance. Carbon nitride (CN) compounds are promising two-dimensional (2D) materials with tunable structures, low cost, facile synthesis, excellent optical properties, and wide bandgaps, yet achieving high κ is hindered by the buckled structures breaking reflection symmetry, the lone pair-bonding electron interactions enhancing anharmonicity, and the long-neglected four-phonon scattering, which are pivotal factors for high κ. Herein, we address these challenges in 2D buckled c-CN via atomic-scale coordination environment optimization and electronic structure regulation, where the unique lone pair electron coordination induces buckling while mitigating lone pair-bonding electron interactions to maintain low anharmonicity. As a result, the c-CN exhibits an ultrahigh κ of 1359 W/mK (three-phonon scattering) and retains 708 W/mK even with four-phonon scattering included, confirming it as a high-κ CN material. This study could provide guidance for atomic-level structure and electronic structure design of high-κ 2D materials for nanoelectronic heat dissipation.

The direct photooxidation of methane to value-added products presents a promising solution for the utilization of abundant natural gas resources. However, there are still great challenges in the production of multiple oxidation products and inevitable overoxidation owing to the difficult manipulation of C-H bond activation and alternative radical formation. Herein, the high-density In(L)-Ov-In-OH frustrated Lewis pairs (FLPs) with Lewis acidic In(L) and Lewis basic In-OH were constructed on the Pt-mIn2O3-x(OH)y photocatalyst to promote the C-H bond activation in CH4. In situ characterization techniques and theoretical calculations revealed that the electron transfer from the bonding orbitals (σ) of CH4 to the unoccupied orbitals of In(L), coupled with the weak electron donation from the In-OH sites to the antibonding orbitals (σ*) of CH4, cooperatively polarized and stretched the C-H bond, thus significantly lowering its dissociation energy barrier. Meanwhile, the tailored Pt-O-In motifs (either Pt nanoparticles or Pt single atoms) on the Pt-mIn2O3-x(OH)y photocatalyst serving as an electron acceptor could precisely modulate the types of reactive oxygen species by altering the adsorption configuration of O2. Benefiting from the synergy of the In(L)-Ov-In-OH FLPs and Pt motifs, both excellent yield and selectivity were obtained for CH3OH or HCHO. Under optimal conditions, Pt nanoparticles supported on mIn2O3-x(OH)y (PtNPs-mIn2O3-x(OH)y) achieved a high CH3OH production rate of 3970.0 μmol g-1 h-1 with 90.9% selectivity, and Pt single atoms coordinated with mIn2O3-x(OH)y (PtSAs-mIn2O3-x(OH)y) delivered an excellent HCHO yield of 10182.4 μmol g-1 h-1 with 84.9% selectivity. This work demonstrated a promising strategy for designing advanced photocatalysts to disentangle the activity-selectivity trade-off in CH4 photooxidation.

The semi-hydrogenation of alkynols to enols represents a vital industrial reaction for fine chemical synthesis, yet developing highly selective non-noble metal catalysts remains an urgent challenge. Herein, we report a Co3O4 nanorod (Co3O4-NR) catalyst with abundant solid-frustrated Lewis pairs (SFLPs) on specifically exposed {110} facets, where coordinatively unsaturated Co2+ acts as Lewis acid site whilst the surface hydroxyl group serves as Lewis base site. The Co3O4-NR catalyst exhibits exceptional performance toward semi-hydrogenation from 3-butyn-1-ol to 3-buten-1-ol with a product yield of 88.2%, which is preponderate to other non-noble metal catalysts. Poisoning experiments, in situ DRIFTS and theoretical calculations verify that the SFLPs sites serve as intrinsic active centers for H2 activation/dissociation and substrate adsorption. The hydrogenation of key intermediate (C4H7O*) is identified as the rate-determining step, where Hδ+ species strongly tethered to surface-OH group suppresses over-hydrogenation and thereby enhances the semi-hydrogenation selectivity. Projected density of states (PDOS) analysis reveals an accelerated hydrogenation kinetics via d-p orbital hybridization between Co 3d orbitals and C 2p orbitals in C4H7O*. This work advances the design of efficient and cost-effective SFLPs-based heterogeneous catalysts, which shows potential application in the synthesis of fine chemicals.

Biosourced polymers and aqueous thermoresponsive polymers have both received broad attention, but the two attributes are rarely merged. Here, furfural-derived alcohol and carboxylic acid are transformed into tetrahydrofuran(THF)-bearing epoxides, tetrahydrofurfuryl glycidyl ether (F2GE) and glycidyl 2-tetrahydrofuroate, by reacting with epichlorohydrin. Ring-opening polymerization catalyzed by an organic Lewis pair occurs in a highly selective manner, producing THF-functionalized polyethers with controlled molar mass (5.6-22.7 kg mol-1) and low dispersity (1.09-1.12). Nonbiosourced (tetrahydrofuran-3-yl)methyl glycidyl ether is also synthesized and polymerized for comparison. The polyethers exhibit high thermal stability, minimal cytotoxicity, and structure-dependent cloud point temperature (Tcp) in water with polyF2GE showing the highest Tcp (24.1-37.3 °C) at all concentrations (0.1-1.0 mg mL-1). Alkali metal halides exhibit variable "salting-in/-out" effects, with Tcp increased by NaI, LiI, or LiBr and decreased by NaCl, NaBr, or KCl. Also interestingly, the THF functionalities allow polyF2GE to selectively adsorb Fe3+ (95.3%) from an aqueous solution containing other ions (Ni2+, Co2+, and Mn2+) above Tcp.

We report an improved synthesis of the Lewis acid-stabilized stibine oxide Ph3SbOB(C6F5)3 (1) and show that it undergoes oxygen-atom transfer to PPh3. The reaction proceeds through a discrete Ph3Sb·B(C6F5)3 Lewis pair, which we have isolated and characterized in solution, and which also mediates trace-water activation to give the hydroxo-antimony(III) adduct (2). These results reveal that suitably polarized stibine oxides can access OAT reactivity not observed in bulky analogues, broadening the chemistry of heavy p-block oxides.

We demonstrate the existence of doubly charged exciton states in strongly screened bilayers of transition metal dichalcogenide layers. These complexes are important because they are preformed electron pairs that can, in principle, undergo Bose-Einstein condensation, in which case they would also form a new type of superconductor, consisting of stable bosons with net charge. Our measurements include 1) continuous control of the doping density with both positive and negative carriers, showing the expected population dependencies on the free carrier density, and 2) measurement of the dependence on magnetic field, showing that this new bound state is a spin triplet. These results imply that it is promising to look for superconductivity in this system.

Constructing frustrated Lewis pairs on defect-engineered biphasic catalysts for polyester depolymerization

Construction of frustrated Lewis pairs based on in-situ nitrogen-doped polymer-derived porous carbon for CO2 capture and conversion

Dual active sites of electron-rich Ni0 and frustrated Lewis pairs of Sr-doped catalysts for efficient fuel steam reforming

The photoelectrocatalytic water splitting was impeded by high thermodynamic energy barriers and slow reaction kinetics of anodic oxygen evolution reactions. Herein, a strategy for constructing frustrated Lewis pairs (FLPs) at...

Structures and reactivities of heterogeneous frustrated Lewis pairs catalysts

Differential ligation alters electronic state and coupling signals of iron-sulfur clusters in flavin-based electron bifurcation.

A bicapped icosahedral cluster, [(Cp*Co)4Fe(CO)B9H11] (Cp* = η5-C5Me5; 1), has been synthesized and structurally characterized. Cluster 1 represents the first closo-metallaborane with a bicapped icosahedral geometry that follows the capped skeletal electron counting rule. Furthermore, a bicapped square antiprism cluster, [(Cp*Co)3B7H9] (2), has been isolated, which obeys Wade's skeletal electron pair (SEP) rule.

A study on bond length compression effect of lone pair electrons in polycyclic heterocyclic quinones

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.

Water reduction using p-block compounds has recently gained attention over traditional methods involving transition-metal complexes. Building on prior work on boron-phosphorus-based frustrated Lewis pairs (FLPs), specifically the bisborylphosphine (BPB) and borylphosphine (BP) systems, we here use density functional theory (DFT) to model water splitting, in which the nucleophilic substitution step plays a key role. Understanding this step computationally is crucial for deriving design rules for water splitting. However, the complete mechanistic details and the influence of substituents on the computed nucleophilic-substitution energy barrier remain unclear. In this theoretical study, we calculate reaction profiles for BPB and BP while systematically varying the substituents on borane (R1) and phosphorus (R2) to modulate steric and electron-withdrawing/donating properties. Our results indicate that BPB exhibits lower barriers than BP. According to the distortion-interaction analysis, when the borane receptor B2 is intermolecular (BP) it undergoes greater geometric distortion upon hydride transfer than in BPB, where the borane receptor is intramolecular. Despite the high computed barriers for BP, these can be reduced (rendering BP competitive with BPB) by incorporating strongly electron-donating R2 substituents at the phosphorus.

ABSTRACT Efficient catalysis of unsaturated hydrocarbon hydrogenation/isomerization reactions is important for realizing sustainable chemical processes and enhancing the whole energy efficiency. However, the development of “one‐pot” catalysts with high activity, excellent selectivity and outstanding stability remains a major challenge. This study presents a novel catalyst design that utilizes NU‐1000 with open metal sites to enhance metal‐molecule interactions and promote selective adsorption. By using a strategic multimetal doping technique Ti/Zr/Hf, homomeric high‐density frustrated Lewis pairs (FLPs) architecture with different coordination metals namely M‐NU‐1000‐X (M=Zr, Hf, Ti, X = 1~6 represented various metal combinations) were obtained. The strategic multimetal doping finely tune FLPs’ acidity/basicity and electron structure favorable for improve acid‐base synergism effect and steric hindrance effect. DFT calculations reveal a mechanism that generated active hydrogen through cleaving H 2 at the FLPs site then attack cycloolefin double bond selectively. The hydrogenation/isomerization mechanism was promoted greatly by catalysis effect induced by metals‐based π anti‐donation effect. Furthermore, we constructed a robust connection model between the calculated Gibbs free energy values of the transition state and some parameter and obtained activation energy barriers based on the descriptor model, thus significantly decreasing huge computational cost. Dynamic Time Warping (DTW) analysis reveals that the dynamic response of polarizability and LUMO energy levels is a key factor determining catalytic activity. The introduction of Ti significantly enhances these dynamic differences, while dynamic site regulation of the local coordination environment further amplifies the differentiation in catalytic performance. A novel approach has been established that integrates electronic structure properties, reaction path evolution, and energy descriptors. This opens a new gateway for developing highly efficient hydrogenation catalysts and provides innovative strategies for catalyst design.

Layered or pseudo-layered crystalline structures are particularly prone to exhibiting pronounced birefringence effects due to their anisotropic nature. In this investigation, we developed a novel strategy for designing birefringent materials with 2D architectures by synergistically combining the structural diversity of V─O coordination groups with lone pair electron functional groups. Guided by this strategy, we successfully synthesized two compounds, LiV3Se2O12 and RbVSeO5. Remarkably, LiV3Se2O12 is grown into a centimeter-sized single crystal using a high-temperature solution method, which is analogous to the "one-pot" approach. This "one-pot" approach not only minimizes chemical waste but also simplifies the growth process, which offers a time-efficient and practical route for obtaining large-sized single crystals. Structurally, LiV3Se2O12 features 2D [V3Se2O12]∞ layers, which are constructed from triangular pyramidal [SeO3] groups and 1D [V3O13]∞ chains. To the best of our knowledge, LiV3Se2O12 exhibits the largest birefringence (experimental Δn = 0.45 at 546 nm) among vanadate and selenate systems, which also surpasses the commercial YVO4 crystal. This exceptional birefringence highlights the potential of LiV3Se2O12 as a promising candidate for future applications in birefringent materials.

In the present study, Stephania kwangsiensis root extracts (SKRE) were first investigated as an innovative, environmentally friendly corrosion inhibitor for Q235 steel in 1 M HCl medium by combining experimental measurements and theoretical calculations. It is indicated that the SKRE inhibitor, which represses both cathodic and anodic reactions, serves as a mixed type inhibitor. The corrosion inhibition efficiency (IE) at 100 mg/L SKRE exceeds 99% when using electrochemical techniques, demonstrating a preeminent anticorrosion capability in acid environments. The IE could still be beyond 92% after 5 days of immersion, suggesting an excellent long-term stability of the SKRE inhibitor. A considerably high IE (more than 98%) could also be achieved at various temperatures. The main active component, cepharanthine (CEPT), adsorbs on the steel surface in a parallel configuration. The presence of isoquinoline rings, dioxole rings, benzene rings, and oxygen atoms could donate profuse π-electrons and lone pair electrons to metals, which facilitates the stable adsorption of SKRE onto the steel surface.

Restricted open-shell Kohn-Sham (ROKS) theory is a widely used approach for accurately describing single-electron excitations. However, a proper treatment of ROKS excited states requires two determinants, which poses challenges for conventional single-determinant energy decomposition analysis (EDA). In this work, we develop a new EDA framework for ROKS states by mapping the problem onto an effective single-determinant form and applying the theories of natural orbitals for chemical valence (NOCV) and occupied-virtual orbitals for chemical valence (OVOCV) to analyze electronic excitations. The goal is to understand an electronic excitation as the union of a primary orbital excitation to convert a closed-shell ground state into an open-shell excited state (defined by an intermediate frozen state that is free of polarization effects), with the secondary polarization or relaxation of other electron pairs (defined by the change from the frozen ROKS state to the final ROKS state). Our theory attaches energy changes and electron promotion numbers to each component and also separates the relaxation process into separate occupied-to-virtual contributions ranked by significance using the OVOCV approach. In this way, our ROKS excitation EDA can yield chemical insights from the energetic contributions of relaxation processes and the accompanying charge redistribution that are not otherwise accessible. The method is demonstrated on several representative examples, including the n → π* and π → π* valence excitations of formaldehyde, the 1sCl → σ* core excitation of HCl, a long-range charge-transfer excitation in the NH3-F2 complex, and the lowest valence excitation of (dimethylamino)benzonitrile (DMABN) with a hydrogen-bonded water molecule, which exhibits notable intramolecular charge transfer (ICT) character in DMABN.