Science China Materials最新文献

Antimony sulfide (Sb₂S₃) solar cells fabricated via hydrothermal deposition have attracted widespread attention. The annealing crystallization process plays a crucial role in achieving optimal crystallinity in hydrothermal Sb₂S₃ thin films. Nevertheless, incomplete crystallization and the loss of sulfur at high-temperature contribute to defect recombination, constraining device performance. Herein, a two-step rapid thermal processing (RTP) annealing strategy is proposed to improve the crystal quality and efficiency of Sb₂S₃ solar cells. The annealing process in Ar protection with atmospheric pressure can suppress S loss caused by saturated vapor pressure. The two-step RTP annealing with the 330°C low-temperature and 370°C high-temperature process ensures high crystallinity and vertical orientations of Sb₂S₃ thin films, accompanied by a reduction in defect concentration from 1.01 × 10¹² to 5.97 × 10¹¹ cm⁻³. The Sb₂S₃ solar cell achieves an efficiency of 8.20% with an enhanced open circuit voltage (V_OC) of 784 mV. The build-in voltage (V_bi) of 1.17 V and irradiation-dependent ideal factor (n) of 1.48 demonstrate enhanced heterojunction quality and suppressed defect recombination in the devices. The presented two-step annealing strategy and physical mechanism study will open new prospects for high-performance Sb₂S₃ solar cells.

The polysulfide shuttling effect is the primary bottleneck restricting the industrial application of Li-S batteries, and the electrocatalytic sulfur reduction reaction (SRR) has emerged as an effective solution. Carbon-based single-atom catalysts (SACs), which promotes SRR, show great potential in inhibiting the shuttling effect of polysulfides. Meanwhile, the optimization and rational design of such catalysts requires a deep understanding to the fundamental SRR mechanism and remains highly nontrivial. In this work, we construct a comprehensive database of carbon-based SACs, covering different coordination patterns, heteroatoms, and transition metals. The SRR activities are determined using density functional theory calculations, revealing a synergistic effect between the p orbital of the heteroatom and the d orbital of the transition metal. This interplay underscores the critical importance of the coordination environment for SRR under the ortho-P₂C₂ structure. Regardless of the transition metal type, the ortho-P₂C₂ coordination pattern significantly enhances the SRR performance of SACs, surpassing the widely reported N₃C₁ and N₄ coordinated graphene-based SACs. Furthermore, heteroatoms with ortho-P₂C₂ may exhibit SRR activity. In a word, by using this comprehensive dataset and data-driven framework, we propose a promising novel class of coordination structure (ortho-P₂C₂ structure) and neglected design principle.

Chronic wounds experiencing infections with multidrug-resistant bacteria can be fatal, and in severe cases can lead to sepsis. Antimicrobial peptides are widely used in the field of wound care for their broad-spectrum antibacterial properties and good anti-drug resistance. We prepared bacterial cell membrane chromatography (BCMC) by extracting cell membranes of bacteria using SiO₂ microspheres as stationary phase. A library of antimicrobial peptides was synthesized in solid phase and screened by BCMC to identify the antimicrobial peptide LKAHR (later named LS5), which is characterized by biosafety, broad-spectrum antibacterial activity, and drug resistance, and a gelatin-based antimicrobial hydrogel (LS5-gel) was prepared to be better applied to wounds. LS5-gel was found to have good in vivo bactericidal properties as well as the ability to promote wound healing in a wound healing model. In the sepsis model, LS5 was found to have a significant inhibitory effect on sepsis infection. It is important for the selection of next-generation antimicrobial drugs and the treatment of chronic wound healing.

Constructing an artificial intelligence interactive system is still challenging due to the lack of an integrated artificial sensing and processing system with high performance. In this work, an artificial tactile perception system with integrated sensing, storage, and computing functions is designed based on silk fibroin composite memristors and piezoresistive pressure sensors. The sensors based on polydimethylsiloxane/silver nanowires can sense the external pressure stimulation with fast response speed. In addition, the composite memristor based on silk fibroin possesses good cyclic stability and synaptic plasticity simulation and acts as an artificial synapse to process tactile information. As a result, the integrated tactile perception system realizes the perception, storage, and processing of pressure information, demonstrating the possibility to simulate the biological tactile perception nervous system. This type of system may promote potential applications in artificial intelligence, such as autonomous driving, wearable, flexible electronic devices, and bionic robots.

The complex and rapidly progressing nature of sepsis calls for the development of multifunctional and rapid-acting therapeutic agents, instead of single-modal treatments. To address this challenge, a biodegradable, easily synthesized, and antibiotic-free multifunctional nanoparticle has been created for sepsis therapy. The nanoparticle was formed by the electrostatic interaction between two endogenous small molecule-derived polymers, poly(lipoic acid) and poly-lysine, and possessed various functions such as antibacterial activity, adsorption of cell-free DNA, scavenging of reactive oxygen and nitrogen species, providing a comprehensive approach to combating sepsis. Treatment using the cecal ligation and puncture (CLP) model confirmed the therapeutic benefits of the nanoparticles, demonstrating reduced levels of reactive oxygen across multiple organs, diminished levels of M1 proinflammatory macrophages, and elevated levels of M2 anti-inflammatory macrophages post-treatment. These findings emphasized the effectiveness of the nanoparticles in sepsis therapy, and properties of degradation, easy preparation, and swift therapeutic response made them promising for the future clinical applications.