ACS Applied Materials & Interfaces最新文献

The field of perovskite optoelectronics and electronics has rapidly advanced, driven by excellent material properties and a diverse range of fabrication methods available. Among them, triple-cation perovskites such as CsFAMAPbI₃ offer enhanced stability and superior performance, making them ideal candidates for advanced applications. However, the multicomponent nature of these perovskites introduces complexity, particularly in how their structural, optical, and electrical properties are influenced by thermal annealing─a critical step for achieving high-quality thin films. Here, we propose a comprehensive mechanistic picture of the thin film formation process of CsFAMAPbI₃ during the thermal annealing step through systematic and comparative analyses, identifying two key thermally induced phase transitions: the crystallization of the perovskite phase facilitated by solvent evaporation and the formation of the PbI₂ phase due to thermal decomposition. Our results reveal that the crystallization process during annealing proceeds from the surface to the bulk of the films, with a significant impact on the film's morphology and optical characteristics. Controlled annealing enhances field-effect transistor device performance by promoting defect passivation and complete perovskite crystallization, while prolonged annealing leads to excessive PbI₂ formation, accelerating ion migration and ultimately degrading device performance. These insights offer valuable guidance for optimizing the design and performance of perovskite-based electronic and optoelectronic devices.

Cancer immunotherapy has revolutionized cancer treatment by harnessing the body's immune system to recognize and attack tumors. Over the past 25 years, the use of blocking antibodies has fundamentally transformed the landscape of cancer therapy. However, despite extensive research, agonist antibodies targeting costimulatory receptors such as ICOS, GITR, OX40, CD27, and 4-1BB have consistently underperformed in clinical trials over the past 15 years, failing to meet the anticipated success. One reason the agonist antibodies failed is that researchers escalated the dose to the highest tolerable level, which can lead to cell exhaustion, especially when used as a single agent. In this study, we introduced novel in situ therapeutic agents by combining a bivalent RNA aptamer of OX40, biR^OX40, which binds to two copies of the OX40 receptor as an agonist, with CpG, a toll-like receptor 9 (TLR9) immune stimulator. These agents were specifically designed for lymphoma treatment, with the dose reduced to the lowest bioactive amount to maximize efficacy while minimizing potential side effects. BiR^OX40 and CpG exhibited a dual immune activation effect and demonstrated a synergistic response even at extremely low dose of 0.32 mg/kg (5.75 μg per mouse) for biR^OX40 and moderate dose of 1.39 mg/kg (25 μg per mouse) for CpG, resulting in remarkable antitumor efficacy. This effect was achieved through the promotion of intratumoral CD8+ T cell proliferation and cytokine secretion, inhibition of regulatory T cell (Treg) proliferation, and enhanced generation and proliferation of memory T cells in immune organs. The agonistic effects of these reagents led to tumor regression not only at the treated sites but also at distant, nontreated locations in the animal models. This outcome highlighted the induction of a robust systemic antitumor immune response, which effectively suppressed tumor recurrence. This in situ combination therapy, utilizing low-dose biR^OX40 alongside CpG, offers a straightforward and widely applicable strategy to enhance immune responses in cancer immunotherapy. This approach overcomes the limitations of high-dose single-agent anti-OX40 therapies (whether antibodies or aptamers), including immune cell exhaustion and diminished efficacy.

The intricacy, diversity, and heterogeneity of cancers make research focus on developing multimodal synergistic therapy strategies. Herein, an oxygen (O₂) self-feeding peroxisomal lactate oxidase (LOX)-based LOX-Ce6-Mn (LCM) was synthesized using a biomineralization approach, which was used for cascade chemodynamic therapy (CDT)/photodynamic therapy (PDT) combination therapies through dual depletion of lactate (Lac) and reactive oxygen species (ROS) generation. After endocytosis into tumor cells, the endogenous hydrogen peroxide (H₂O₂) can be converted to O₂ by the catalase-like (CAT) activity of LCM, which can facilitate the catalytic reaction of LOX to consume more Lac and alleviate tumor hypoxia to enhance the generation of singlet oxygen (¹O₂) upon light irradiation. In addition, the H₂O₂ produced by LOX catalysis and oxidase-like (OXD) activity of LCM can be catalyzed into highly toxic hydroxyl radicals (^•OH) via the Fenton-like reaction, enhancing oxidative damage to tumor cells. Both in vitro and in vivo experiments confirmed that LCM significantly promoted ROS accumulation and effectively inhibited tumor growth by inducing tumor cell autophagy under the combined effect of Lac depletion and CDT with PDT. Therefore, integrally designed LCM for reprogramming metabolism and the tumor microenvironment offers a promising multimodal strategy for tumor treatments.

The actual ORR catalytic activity of perovskite materials is significantly lower than the theoretical value due to their inherently low specific surface area and significant segregation of inactive oxygen ions on the surface. This study reports a sol-gel synthesis approach that employs glucose as a structural regulator to fabricate La_0.7Sr_0.3MnO₃ (LSM) perovskites. Compared with the original LSM (12.56 m²·g^-1), LSM-Y2 exhibits a higher specific surface area (19.43 m²·g^-1) and enhanced ORR catalytic activity. Electrochemical results show that the initial potential and half-wave potential of LSM-Y2 are positively shifted by 35 and 85 mV, respectively, with a 1.29-fold increase in intrinsic catalytic activity. Additionally, the performance of the Zn-air batteries is superior to that of the original LSM, with a peak power density of 115 mW·cm^-2 and an energy density of 858 Wh·kg^-1. The enhanced ORR catalytic activity of LSM-Y2 is attributed to the optimization of Mn e_g orbital occupancy on the catalyst surface, facilitated by glucose introduction, and the improved adsorption of oxygen intermediates, resulting from the increased oxygen vacancy concentration. Additionally, the increased specific surface area and porosity of LSM-Y2 provided more active sites for the catalytic process, further enhancing ORR performance. This study not only elucidates the mechanism by which glucose influences the ORR catalytic activity of La_0.7Sr_0.3MnO₃ perovskite but also presents a strategy for developing perovskite catalysts with superior ORR catalytic performance.

Aqueous sodium-ion batteries (SIBs) are gradually being recognized as viable solutions for large-scale energy storage because of their inherent safety as well as low cost. However, despite recent advancements in water-in-salt electrolyte technologies, the challenge of identifying anode materials with sufficient specific capacity persists, complicating the wider adoption of these batteries. This study introduces an innovative and straightforward approach for synthesizing vanadium oxide laser-scribed graphene (VO_x-LSG) composites, which function as effective anode materials in aqueous sodium-ion batteries. By combining a rapid laser-scribing technique with precise thermal control, the method not only allows for changing the morphology of the vanadium oxide, but also tuning its oxidation state. This is achieved while embedding these electrochemically active particles within a highly conductive graphene scaffold. When paired with a Prussian blue-based cathode (Na_1.88Mn[Fe(CN)₆]_0.97) in a concentrated NaClO₄-based aqueous electrolyte, the battery's charge storage mechanism is found to be largely surface-controlled, leading to exceptional rate performance. The full cell demonstrates specific capacities of 128 mA h/g@0.05 A/g and 65.6 mA h/g@1 A/g, with an energy density of 47.7 W h/kg, outperforming many existing aqueous sodium-ion batteries. This strategy offers a promising path forward for integrating efficient, eco-friendly, and low-cost anode materials into large energy storage devices and systems.

The inhibition of residual tumor recurrence while repairing bone defects poses a challenging issue for postoperative osteosarcoma treatment. Here, we develop a self-assembling peptide hydrogel (GelA) for the targeted delivery of cisplatin (CDDP), aiming to integrate postoperative tumor inhibition with bone defect repair. GelA exhibits exceptional biocompatibility, high loading capacity for CDDP, and superior bone adhesion. After in situ injection to bone defects, CDDP-loaded hydrogel GelA-CDDP demonstrates a strong affinity for hydroxyapatite, thereby facilitating optimal bone adhesion and prolonging the retention time of CDDP in a postoperative wound. Furthermore, GelA-CDDP can regulate the distribution and release behavior of CDDP, minimizing off-target effects and optimizing the therapeutic outcomes of chemotherapy and osteogenesis. Finally, in the orthotopic osteosarcoma transplantation model in mice, postoperative treatment with GelA-CDDP significantly inhibits residual osteosarcoma recurrence as well as repair of bone defects through synergistic osteogenesis promotion and osteoclastic inhibition. We believe that this hydrogel-based therapy strategy holds great promise in achieving simultaneous tumor inhibition and bone defect repair for postoperative osteosarcoma treatment.

High defect concentrations at the interfaces are the basis of charge extraction losses and instability in perovskite solar cells. Surface engineering with organic cations is a common practice to solve this issue. However, the full implications of the counteranions of these cations for device functioning are often neglected. In this work, we used 4-fluorophenethylammonium cation with varying halide counteranions for the modification of both interfaces in methylammonium-free Pb-based n-i-p devices, observing significant differences among iodide, bromide, and chloride. The cation treatment of the buried and top interfaces resulted in improved surface quality of the perovskite films and largely improved carrier dynamics with reduced nonradiative recombination. Consequently, the optimal interface-modified methylammonium-free perovskite solar cells surpassed 20% efficiency and demonstrated remarkable operational stability. Our findings underscore the potential of comprehensive surface engineering strategies in advancing the perovskite film and device quality, thereby facilitating their broader and more successful applications.

A transistor design employing all vertically stacked components has attracted considerable attention due to the simplicity of the fabrication process and the high conductivity easily realized by achieving nanolevel short channel lengths with two-dimensional current paths. However, fundamental issues, specifically the blocking of the gate electrical field to the semiconductive channel layer and high leakage current at the "off" state, have impeded this configuration in becoming a major transistor design. To address these issues, it has been proposed to introduce a blocking layer (BL) with embedded hole structures and source electrode with embedded hole structures, enhancing gate field penetration and carrier modulation. The hole structure embedded in the source and the BL on the drain induced a desirable combined effect of gate field penetration and carrier pathway modulation. The align accuracy and the hole size difference between BL and source electrode were confirmed as the most important design parameters for high performance of a transistor. We therefore proposed a self-aligning lithography method using a built-in mask that allows high alignment accuracy between the source hole structure and the BL hole structure on the drain over a large area without a high-resolution process system. This method also enables easy and fast fabrication of nanoscale channels with high performance. This design resulted in a transistor with an output of 28 mA/cm² and an on-off ratio exceeding 10⁶ at 1 mV of V_DS. However, at 3 V of V_DS, the off-current increased significantly due to short-channel effects in the all metal electrode design. To solve this issue, Fermi level-tunable graphene replaced metal electrodes, maintaining an off-current below 10 pA and an on-off ratio around 10⁷ at 3 V. In addition, the device demonstrates robust electrical properties to light without any special treatment and is stable with a threshold voltage shift of less than 1 V under bias stress. This study demonstrates that the proposed vertical transistor design is a viable candidate as a new major transistor design for various applications.