On‐the‐Fly Synthesis of Freestanding Spin‐Crossover Architectures With Tunable Magnetic Properties
Abstract
Abstract Spin‐crossover (SCO) molecular‐based switches have shown promise across a range of applications since their discovery, including sensing, information storage, actuators, and displays. Yet limited processability remains a barrier to their real‐world implementation, as traditional methods for integrating SCO materials into polymer matrices are often complex, expensive, and prone to producing uneven material distributions. Herein, we demonstrate how 3D flow‐focusing chemistry enables unprecedented control for the direct fabrication of SCO composite materials, addressing key challenges in processability, scalability, and cost. By using a 3D coaxial flow‐focusing microfluidic device, we simultaneously synthesize [Fe(Htrz) 2 (trz)](BF 4 ) and achieve its homogeneous incorporation into alginate fibers in a continuous manner. The device’s versatility allows for precise manipulation of the reaction‐diffusion (RD) zone, resulting in SCO composite fibers with tunable physicochemical and magnetic properties. Additionally, we demonstrate the ability to isolate these fibers as freestanding architectures and highlight the potential for printing them with defined shapes. Finally, we show that the 3D control of the RD zone granted by continuous flow microfluidic devices offers precise spatiotemporal control over the distribution of SCO complexes within the fibers, effectively encoding SCO materials into them. SCO‐encoded fibers can seamlessly combine adaptability and functionality, offering innovative solutions for application‐specific customization.
Article Details
Authors (13)
Anh Tuan Ngo
Departament de Ciència dels Materials i Química Física and Institut de Química Teòrica i Computacional Universitat de Barcelona Diagonal 645 Barcelona 08028 Spain
David Aguilà
Departament de Química Inorgànica i Orgànica, and IN2UB Universitat de Barcelona Diagonal 645 Barcelona 08028 Spain
João Pedro Vale
Associate Laboratory in Chemical Engineering (ALICE) Engineering Faculty of Porto University Porto 4200‐465 Portugal
Semih Sevim
Multi-Scale Robotics Lab, Institute of Robotics and Intelligent Systems, ETH Zürich, Tannenstrasse 3, Zürich CH-8092, Switzerland
Michele Mattera
Departament de Ciència dels Materials i Química Física and Institut de Química Teòrica i Computacional Universitat de Barcelona Diagonal 645 Barcelona 08028 Spain
Jordi Díaz‐Marcos
Unitat de Tècniques Nanomètriques Centres Científics i Tecnològics de la Universitat de Barcelona (CCiTUB) Carrer de Lluís Solé i Sabarís, 1, Les Corts Barcelona 08028 Spain
Ramon Pons
Institute for Advanced Chemistry of Catalonia (IQAC‐CSIC) Barcelona Spain
Guillem Aromí
Departament de Química Inorgànica i Orgànica Universitat de Barcelona Diagonal 645 Barcelona 08028 Spain
Bumjin Jang
Hanyang University ERICA 55, Hangyangdaehak‐ro, Sangrok‐gu Ansan‐si Gyeonggi‐do 15588 South Korea
Salvador Pané
Multi-Scale Robotics Lab, Institute of Robotics and Intelligent Systems, ETH Zürich, Tannenstrasse 3, Zürich CH-8092, Switzerland
Tiago Sotto Mayor
Associate Laboratory in Chemical Engineering (ALICE) Engineering Faculty of Porto University Porto 4200‐465 Portugal
Mario Palacios‐Corella
Departament de Ciència dels Materials i Química Física Institut de Química Teòrica i Computacional Universitat de Barcelona Barcelona 08028 Spain
Josep Puigmartí‐Luis
Departament de Ciència de Materials i Química Física Universitat de Barcelona C/ Martí i Franquès, 1–11 Barcelona 08028 Spain