Pacanowska Aleksandra, Regueiro Alejandro, Clemente-León Miguel, Coronado Eugenio, Forment-Aliaga Alicia, Fitta Magdalena
Institute of Nuclear Physics Polish Academy of Sciences, Radzikowskiego 152, 31-342 Kraków, Poland.
Instituto de Ciencia Molecular, Universitat de València, Catedrático José Beltrán 2, 46980 Paterna, Spain.
ACS Appl Nano Mater. 2025 Aug 6;8(32):15999-16007. doi: 10.1021/acsanm.5c02764. eCollection 2025 Aug 15.
Developing strategies that transform crystalline molecular materials into processable forms is crucial for enabling their manipulation and integration into devices. This challenge is particularly relevant for bistable systems such as spin-crossover nanoparticles, which are often difficult to handle. Embedding these nanoparticles into organic polymers has emerged as a promising way to overcome these limitations. In this work, we investigated a series of iron-(II) triazole-based spin-crossover nanoparticles with the size of 37.0 ± 5 nm (, 55.4 ± 9.7 nm (), and 116.8 ± 15.5 nm () incorporated into electrospun PVP fibers. Magnetic susceptibility measurements demonstrated that the hysteretic spin transition is preserved in all composites, with a significant broadening of their coercive fields. The most significant effect is observed in the cooling mode of the composites based on nanoparticles of bigger size, and , which is shifted to lower temperatures compared to their powder counterparts. A contrasting analysis of electrospun fibers and drop-casted films highlighted enhanced magnetic hysteresis and improved fiber stability, indicating a matrix geometry effect on spin crossover behavior. These findings underscore the potential of electrospun spin-crossover composite materials not only for creating flexible and scalable functional fabrics but also for precisely tailoring magnetic properties and enhancing robust spin-crossover behavior.
开发将晶体分子材料转变为可加工形式的策略对于实现其操控并集成到设备中至关重要。这一挑战对于诸如自旋交叉纳米颗粒等双稳态系统尤为相关，这类系统通常难以处理。将这些纳米颗粒嵌入有机聚合物已成为克服这些限制的一种有前景的方法。在这项工作中，我们研究了一系列尺寸为37.0±5nm（）、55.4±9.7nm（）和116.8±15.5nm（）的基于铁（II）三唑的自旋交叉纳米颗粒，它们被掺入电纺PVP纤维中。磁化率测量表明，所有复合材料中都保留了滞后自旋转变，其矫顽场显著变宽。在基于较大尺寸纳米颗粒（和）的复合材料的冷却模式中观察到最显著的效果，与它们的粉末对应物相比，其转变温度向更低温度移动。对电纺纤维和滴铸薄膜的对比分析突出了增强的磁滞和改善的纤维稳定性，表明基质几何形状对自旋交叉行为有影响。这些发现强调了电纺自旋交叉复合材料不仅在制造柔性且可扩展的功能性织物方面的潜力，而且在精确调整磁性能和增强稳健的自旋交叉行为方面的潜力。
