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The synthesis of photocatalysts with rapid photogenerated electron transfer, strong reactant adsorption, and activation is urgent to promote photocatalytic NO oxidation. Herein, we construct a series of carbon nanotube (CNT)-threaded CeO2 mesocrystalline photocatalysts applying the microwave thermal method. The noncontinuous CNT-threaded structure provides two interfacial charge transport pathways for the efficient separation of photogenerated carriers. The introduction of CNTs induces mesocrystalline CeO2 with surface Ce3+ and oxygen vacancies, which is in favor of adsorption and activation for reactants, further facilitating a deep oxidation pathway for NO removal. The optimal photocatalyst exhibits a remarkable conversion ratio for NO oxidation and NO3 - selectivity in a recyclable way. [ABSTRACT FROM AUTHOR]

The recent synthesis of "borophane" polymorphs through hydrogenation has promoted the development of boron-based two-dimensional (2D) materials. In this work, the electronic structures and transport properties of hydrogenated borophene are investigated using first-principles calculations. The results show that the metallic character is preserved after hydrogenation, whereas electronic structures are greatly modulated by the position and number of introduced hydrogen atoms. More importantly, the presence of three-center-two-electron (3c-2e) bonds results in the formation of distorted Dirac points below the Fermi level in rect-1Hbridge and rect-2H borophane structures. The transport properties and the current–voltage (I–V) curve characters in those borophane structures can be efficiently modulated by the type of hydrogenations. Different hydrogenation patterns dominate diverse electronic transport behaviors. Such hydrogen atom-participant transport states endow borophane structures with potential applications in boron-based 2D electronics devices. [ABSTRACT FROM AUTHOR]

Twenty stable geometries of [Fe.sub.3][C.sub.2] are found using spinpolarized DFT calculations. The stability of all clusters is confirmed by vibrational frequency analysis.

The size effect of zirconia particles on the catalysis of Ni metal for CO2 re-forming of methane is explored. It is revealed that for the first time that when the sizes of zirconia particles become smaller than 25 nm, the oxide forms nanocomposite catalysts with size-comparable Ni-metal nanocrystals.

Four new zinc(II) complexes based on the same ligand, {Zn(ptp)(H2O)]2 (1), [Zn(ptp)(CH3OH)]n (2), [Zn(ptp)]n (3), and {[Zn3(ptp)3](DMF)2(H2O)}n (4) [H2ptp = 2,3-bis(pyridine-2-yl)-5,6-di-1H-tetrazol-5-ylpyrazine], have been synthesized by solvothermal methods. All of the complexes have been structurally characterized by elemental analysis, IR, powder X-ray diffraction, and single-crystal X-ray diffraction. Structural analyses show that complex 1 possesses a centrosymmetrical neutral dinuclear structure and 2 has 1D right-handed helical chains, with the 21 axis expanding along the crystallographic b direction; 3 features a 2D chiral-layered structure with (6,3) net, and complex 4 displays a 3D porous framework with (4,122) topology. The various architectures (0D, 1D, 2D, and 3D) of these four complexes indicated that reaction conditions (temperature and solvent) play an important role in the formation of such coordination structures; namely, various structures can be obtained from the same reactants by controlling and changing the reaction conditions in this system. The luminescent properties of all of the complexes and the corresponding ligand have been investigated in the solid state at room temperature. Moreover, adsorption properties (N2, H2, O2, CO2, and CH4) of the 4a (desolvated 4) have been studied, and the results show that 4a possesses a moderate capability of gas sorption for N2, H2, O2, and CO2 gases, with high selectivity ratios for O2 over H2 at 77 K and CO2 over CH4 at 273 K. [ABSTRACT FROM AUTHOR]

The spontaneous vesicle formation and fusion of A2n(B2)n(n= 2−10) type comb-like block copolymers with semiflexible hydrophobic backbone are studied via dissipative particle dynamics (DPD) simulations. By systemically varying the solvent condition, we construct a phase diagram to indicate the thermodynamically stable region for vesicles. The spontaneous fusion between the vesicles is studied, whose mechanism is as follows: first, a stalk is formed between the vesicles; then, the holes appear in both vesicles near the feet of the stalk; finally, the stalk bends to circle the holes and the fusion process is completed. This fusion pathway is similar to that observed in Monte Carlo simulations and dynamic self-consistent filed theory but different from those reported in coarse-grained molecular dynamics and DPD simulations. The main reason for the difference may be attributed to the molecular structures used in different simulation techniques. [ABSTRACT FROM AUTHOR]

Serving as neuromorphic hardware accelerators, memristors play a crucial role in large-scale neuromorphic computing. Herein, two-terminal memristors utilizing amorphous indium-gallium-zinc oxide (a-IGZO) are fabricated through room-temperature sputtering. The electrical characteristics of these memristors are effectively modulated by varying the oxygen flow during the deposition process. The optimized a-IGZO memristor, fabricated under 3 sccm oxygen flow, presents a 5 × 10 3 ratio between its high- and low-resistance states, which can be maintained over 1 × 10 4 s with minimal degradation. Meanwhile, desirable properties such as electroforming-free and self-compliance, crucial for low-energy consumption, are also obtained in the a-IGZO memristor. Moreover, analog conductance switching is observed, demonstrating an interface-type behavior, as evidenced by its device-size-dependent performance. The coexistence of negative differential resistance with analog switching is attributed to the migration of oxygen vacancies and the trapping/detrapping of charges. Furthermore, the device demonstrates optical storage capabilities by exploiting the optical properties of a-IGZO, which can stably operate for up to 50 sweep cycles. Various synaptic functions have been demonstrated, including paired-pulse facilitation and spike-timing-dependent plasticity. These functionalities contribute to a simulated recognition accuracy of 90% for handwritten digits. Importantly, a one-selector one-memristor (1S1M) architecture is successfully constructed at room temperature by integrating a-IGZO memristor on a TaO x -based selector. This architecture exhibits a 10 7 on/off ratio, demonstrating its potential to suppress sneak currents among adjacent units in a memristor crossbar.

Cancer-associated fibroblasts (CAFs) assist in breast cancer (BRCA) invasion and immune resistance by overproduction of extracellular matrix (ECM). Herein, we develop FPC@S, a photodynamic immunomodulator that targets the ECM, to improve the photodynamic immunotherapy for fibrotic BRCA. FPC@S combines a tumor ECM-targeting peptide, a photosensitizer (protoporphyrin IX) and an antifibrotic drug (SIS3). After anchoring to the ECM, FPC@S causes ECM remodeling and BRCA cell death by generating reactive oxygen species (ROS) in situ . Interestingly, the ROS-mediated ECM remodeling can normalize the tumor blood vessel to improve hypoxia and in turn facilitate more ROS production. Besides, upon the acidic tumor microenvironment, FPC@S will release SIS3 for reprograming CAFs to reduce their activity but not kill them, thus inhibiting fibrosis while preventing BRCA metastasis. The natural physical barrier formed by the dense ECM is consequently eliminated in fibrotic BRCA, allowing the drugs and immune cells to penetrate deep into tumors and have better efficacy. Furthermore, FPC@S can stimulate the immune system and effectively suppress primary, distant and metastatic tumors by combining with immune checkpoint blockade therapy. This study provides different insights for the development of fibrotic tumor targeted delivery systems and exploration of synergistic immunotherapeutic mechanisms against aggressive BRCA.

The breaking of the out-of-plane symmetry makes a two-dimensional (2D) Janus monolayer a new platform to explore the coupling between ferroelectricity and ferromagnetism. Using density functional theory in combination with Monte Carlo simulations, we report a novel phase-switchable 2D multiferroic material VInSe 3 with large intrinsic out-of-plane spontaneous electric polarization and a high Curie temperature ( T c ). The structural transition energy barrier between the two phases is determined to be 0.4 eV, indicating the switchability of the electric polarizations and the potential ferroelectricity. Carrier doping can boost the Curie temperature above room temperature, attributing to the enhanced magnetic exchange interaction. A transition from the ferromagnetic (FM) state to the antiferromagnetic (AFM) state can be induced by carrier doping in octahedra-VInSe 3 , while FM coupling is well-preserved in tetrahedron-VInSe 3 , which can be regulated to be either an XY or Ising magnet at an appropriate carrier concentration. These findings not only enrich the family of high -T c low-dimensional monolayers but also offer a new direction for the design and multifunctional application of multiferroic materials.

A novel method to synthesize 4-alkylpyrimidines by the mechanochemical magnesium-mediated Minisci reaction of pyrimidine derivatives and alkyl halides has been reported. The reaction process operates with a broad substrate scope and excellent regioselectivity under mild conditions with no requirement of transition-metal catalysts, solvents, and inert gas protection. The practicality of this protocol has been demonstrated by the up-scale synthesis, mechanochemical product derivatization, and antimalarial drug pyrimethamine preparation.

One of the main challenges for advanced metallic nanoparticles (NPs) supported functional perovskite catalysts is the simultaneous achievement of a high population of NPs with uniform distribution as well as long-lasting high performance. These are also the essential requirements for optimal electrode catalysts used in solid oxide fuel cells and electrolysis cells (SOFCs and SOECs). Herein, we report a facile operando manufacture way that the crystal reconstruction of double perovskite under reducing atmosphere can spontaneously lead to the formation of ordered layered oxygen deficiency and yield segregation of massively and finely dispersed NPs. The real-time observation of this emergent process was performed via an environmental transmission electron microscope. Density functional theory calculations prove that the crystal reconstruction induces the loss of coordinated oxygen surrounding B-site cations, serving as the driving force for steering fast NP growth. The prepared material shows promising capability as an active and stable electrode for SOFCs in various fuels and SOECs for CO2 reduction. The conception exemplified here could conceivably be extended to fabricate a series of supported NPs perovskite catalysts with diverse functionalities.

The spontaneous vesicle formation and fusion of A(2n)(B(2))(n) (n = 2-10) type comb-like block copolymers with semiflexible hydrophobic backbone are studied via dissipative particle dynamics (DPD) simulations. By systemically varying the solvent condition, we construct a phase diagram to indicate the thermodynamically stable region for vesicles. The spontaneous fusion between the vesicles is studied, whose mechanism is as follows: first, a stalk is formed between the vesicles; then, the holes appear in both vesicles near the feet of the stalk; finally, the stalk bends to circle the holes and the fusion process is completed. This fusion pathway is similar to that observed in Monte Carlo simulations and dynamic self-consistent filed theory but different from those reported in coarse-grained molecular dynamics and DPD simulations. The main reason for the difference may be attributed to the molecular structures used in different simulation techniques.

On the basis of density-functional theory and all-electron numerical basis set, 20 stable isomers of Fe(3)C(2) cluster are found through optimization calculations and frequency analysis from 108 initial structures. A nonplanar C(s) structure with nonet spin multiplicity and 482.978 kcal/mol of binding energy is found as the candidate of global minimum geometry of Fe(3)C(2) cluster. The binding energies, the energy gaps between the highest occupied molecular orbital and the lowest unoccupied molecular orbital, and the magnetic moments of all the isomers are reported. The relationship between the molecular properties and geometrical structures is also investigated.