Science China Materials最新文献

We report a simple, effective, and universal lattice reconstruction approach to improve the quality of perovskite films by using nonpolar solvents with high Gutmann donor numbers (DNs). We find that high-DN nonpolar solvents, for instance, ethyl acetate, can interact with perovskite precursors. Such a solvent can make the perovskite lattice more ordered and “harder” and promote the formation of heterostructures with low-dimensional perovskite impurities and residual solvent molecules. As a result, the lattice-reconstructed perovskite films exhibit reduced defect densities and suppressed ion migration. The resultant mixed-halide blue perovskite light-emitting diodes (PeLEDs) show greatly enhanced tolerance to high driving current densities and voltages, demonstrating high brightness, outstanding color stability and low efficiency roll-off. Our work provides a deep understanding of the interactions between nonpolar solvents and perovskites and offers useful guidelines for further development of high-power PeLEDs.

The emergence of antibiotic-resistant bacteria has become a major threat to global public health and has prompted the discovery of antibiotic alternatives. Natural antimicrobial peptides (AMPs) confer a unique non-specific membrane rupture mechanism, showing great potential in killing drug-resistant bacteria. However, natural AMPs have certain weaknesses, including stability and toxicity issues, which seriously hinder their in vivo applications. Synthetic AMPs possess similar characteristics to natural AMPs, including positive charges, amphiphilicity, and the ability to fold into diverse secondary structures. These properties are essential for AMPs penetration into membranes, allowing them to exhibit antimicrobial effects. Moreover, supramolecular self-assembly, facilitated by hydrophobic interaction, hydrogen bonding, π-π stacking, and electrostatic interaction, can generate nanoparticles, nanotubes, nanofibers, and hydrogels with well-defined nanoarchitectures. Utilizing peptide self-assembly to form various nanoarchitectures is an effective approach for generating antibacterial nanomaterials, offering potential advantages such as enhanced antibacterial properties, improved stability, and reduced cytotoxicity. This review highlights recent advancements in tailoring supramolecular AMPs to create diverse nano-architectures for combating infectious diseases.

The synthetic path of a catalyst determines its morphology, species, and performance, and in-situ monitoring the catalyst formation process is fascinating and challenging. Herein, a newly developed synchrotron radiation small-angle X-ray scattering/X-ray diffraction/X-ray absorption fine structure (SAXS/XRD/XAFS) combined technique was used to in-situ monitor the isothermal-isobaric synthesis process of CO₂-assisted (BiO)₂CO₃ (BOC) photocatalyst, and the atomic near-neighbor structure, crystalline structure and nanoscale particle size evolution with reaction time were simultaneously captured. The results show that both polyvinyl pyrrolidone and CO₂ formed uniformly-distributed nano-sized scatterers in the Bi-based precursor solution, presenting short-range ordered structures to a certain extent. The as-prepared BOC catalytic particles underwent the evolution process of initial Bi(OH)₃ precipitate, early-stage formed KBiO₂ molecules, intermediate amorphous (BiO)₄CO₃(OH)₂ nanoparticles, and finally crystallized flower-like BOC particles self-assembled by nanosheets. The flower-like BOC particles, Bi/BOC composite, and Bi nanospheres were further prepared with different synthesis paths. Flower-like BOC particles showed the best photocatalytic degradation performance of RhB. Scavenger experiment and theoretical calculation revealed the photocatalytic mechanisms of BOC. This work has implications for path-dependent synthesis of other catalysts.

Sodium metal batteries are emerging as promising energy storage technologies owing to their high-energy density and rich resources. However, the challenge of achieving continuous operation at high areal capacity hinders the application of this system. Here, a robust two-dimensional tin/sodium–tin alloy interface was introduced onto an Al substrate as an anode via an industrial electroplating strategy. Unlike the widely accepted in situ formation of Na₁₅Sn₄ alloys, the formation of Na₉Sn₄ alloys results in a semi-coherent interface with sodium due to low lattice mismatch (20.84%), which alleviates the lattice stress of sodium deposition and induces subsequent dense sodium deposition under high areal capacity. In addition, the strong interaction of Sn with anions allows more PF₆⁻ to preferentially participate in the interfacial solvation structure, thereby facilitating the formation of a thin (10 nm) NaF-rich solid electrolyte interface. Therefore, the substrate can withstand a high areal capacity of 5 mA h cm⁻², exhibiting a high average Coulombic efficiency of 99.7%. The full battery exhibits long-term cycling performance (600 cycles) with a low decay rate of 0.0018% per cycle at 60 mA g⁻¹.

Carbon-based anode materials are widely used in various battery energy storage systems due to their low cost, wide source, high conductivity and easy morphology control. However, current commercially available anode materials as active materials for lithium-/sodium-ion batteries generally suffer from large volume changes and poor rate performance. In response, we synthesized defect-rich N, S co-doped two dimensional (2D) nanosheet-assembled porous carbon microspheres (N, S-PCS) via simple hydrothermal, carbonization and etching process based on the principle of Schiff base reaction. The N, S-PCS structure is thus constructed by removing Fe₇S₈ nanoparticles from the carbon skeleton to form porous microspheres with N, S doping. Therefore, the micromorphology characteristic, pore structure and electro-conductivity of carbon materials are effectively optimized via heteroatom doping and surface engineering. As expected, the prepared N, S-PCS electrodes exhibit excellent electrochemical performance in both lithium-ion and sodium-ion batteries. For lithium-ion batteries, it achieves reversible capacities of 1045 and 237 mAh g⁻¹ at 0.1 and 20 A g⁻¹, respectively. For sodium-ion batteries, it shows good cycling stability with a capacity of 157 mAh g⁻¹ after 500 cycles at 1 A g⁻¹. Experimental and theoretical calculation results confirm that the N, S co-doping strategies help to improve the structural stability, shorten the ion diffusion paths, and promote the reaction kinetics, thus achieving excellent electrochemical performance. This work is instructive for the practical application of nonmetal doping functionalized porous carbon structures for metal-ion batteries.

Embedded phase-change random-access memory (ePCRAM) applications demand superior data retention in amorphous phase-change materials (PCMs). Traditional PCM design strategies have focused on enhancing the thermal stability of the amorphous phase, often at the expense of the crystallization speed. While this approach supports reliable microchip operations, it compromises the ability to achieve rapid responses. To address this limitation, we modified ultrafast-crystallizing Sb thin films by incorporating Sc dopants, achieving the highest 10-year retention temperature (∼175°C) among binary antimonide PCMs while maintaining a sub-10-ns SET operation speed. This reconciliation of two seemingly contradictory properties arises from the unique kinetic features of the 5-nm-thick Sc₁₂Sb₈₈ films, which exhibit an enlarged fragile-to-strong crossover in viscosity at medium supercooled temperature zones and an incompatible sublattice ordering behavior between the Sc and Sb atoms. By tailoring the crystallization kinetics of PCMs through strategic doping and nanoscale confinement, we provide new opportunities for developing robust yet swift ePCRAMs.

Multiple myeloma (MM) is an incurable malignancy of clonal plasma cells, characterized by high relapse rates and rapid development of drug resistance. The emergence of proteasome inhibitors has dramatically improved the therapeutic effect of MM; however, side effects and drug resistance still negatively affect the survival rate of MM. Nano-medicine has become a promising field for therapeutic innovation owing to its biodegradability and biocompatibility. Nanoparticles (NPs), when combined with MM therapeutic drugs, can reduce side effects, increase treatment efficacy, and alleviate drug resistance, providing a new direction for the treatment of MM. Restructuring drugs with NPs presents an ideal strategy for ongoing studies aimed at more effective therapies. Additionally, clinical nanomedicine research has yielded new opportunities for MM treatment. This review, guided by the development of MM therapeutic drugs, summarizes the past 20 years of research progress and breakthroughs in NP-based systems for treating MM and improving drug targeting ability.

Two new thermally activated delayed fluorescence (TADF) molecules, 13-(2,12-di-tert-butyl-5,9-dioxa-13b-boranaphtho[3,2,1-de]anthracen-7-yl)-5,5-dimethyl-5,13-dihydrobenzo[4,5]thieno[3,2-c]acridine (BOBT) and 13-(4-(dimesitylboranyl)-3,5-dimethylphenyl)-5,5-dimethyl-5,13-dihydrobenzo[4,5]thieno[3,2-c]acridine (BPBT), are constructed via connecting the 5,5-dimethyl-5,13-dihydrobenzo[4,5]thieno[3,2-c]acridine (BTDMAC) donor (D) with triarylboron or oxygen-bridged cyclized boron acceptors (A), respectively. In comparison with the photoluminescence quantum yield (PLQY) of 84% for BPBT, BOBT shows a higher PLQY of 100%, due to the multi-resonance effect of the boron-oxygen skeleton. In addition, the D-A-type molecular structural characteristic endows the boron-containing BOBT emitter with a fast reverse intersystem crossing rate on the order of 10⁶ s⁻¹. The sky-blue organic light-emitting diode (OLED) employing the BOBT emitter achieves state-of-the-art device performances with a high external quantum efficiency of 32.6%.