Spin-crossover nanoparticles anchored on MoS2 layers for heterostructures with tunable strain driven by thermal or light-induced spin switching

• Published in: Nature chemistry 2021-11, Vol.13 (11), p.1101-1109
• Main Authors: Torres-Cavanillas, Ramón, Morant-Giner, Marc, Escorcia-Ariza, Garin, Dugay, Julien, Canet-Ferrer, Josep, Tatay, Sergio, Cardona-Serra, Salvador, Giménez-Marqués, Mónica, Galbiati, Marta, Forment-Aliaga, Alicia, Coronado, Eugenio
• Format: Article
• Language: English
• Subjects: 639/925/357; 639/925/357/1018; 639/925/357/354; 639/925/357/995; 639/925/357/997; Analytical Chemistry; Biochemistry; Chemistry; Chemistry and Materials Science; Chemistry/Food Science; Composite materials; Crossovers; Heterostructures; Inorganic Chemistry; Irradiation; Light effects; Light irradiation; Molybdenum disulfide; Nanoparticles; Optical properties; Optoelectronic devices; Organic Chemistry; Physical Chemistry; Radiation; Two dimensional materials
• ISSN: 1755-4330; 1755-4349
• DOI: 10.1038/s41557-021-00795-y

In the past few years, the effect of strain on the optical and electronic properties of MoS 2 layers has attracted particular attention as it can improve the performance of optoelectronic and spintronic devices. Although several approaches have been explored, strain is typically externally applied on the two-dimensional material. In this work, we describe the preparation of a reversible ‘self-strainable’ system in which the strain is generated at the molecular level by one component of a MoS 2 -based composite material. Spin-crossover nanoparticles were covalently grafted onto functionalized layers of semiconducting MoS 2 to form a hybrid heterostructure. Their ability to switch between two spin states on applying an external stimulus (light irradiation or temperature change) serves to generate strain over the MoS 2 layer. A volume change accompanies this spin crossover, and the created strain induces a substantial and reversible change of the electrical and optical properties of the heterostructure. Spin-crossover nanoparticles have been covalently grafted onto a semiconducting MoS 2 layer to form a self-strainable heterostructure. Under light or thermal stimulus, the nanoparticles switch between their high- and low-spin states, in which they have different volumes. This generates a reversible strain over the MoS 2 layer and, in turn, alters the electrical and optical properties of the heterostructure.