Martino, Edoardo Santos-Cottin, David Le Mardelé, Florian Semeniuk, Konstantin Pizzochero, Michele Čerņevičs, Kristia̅ns Baptiste, Benoît Delbes, Ludovic Klotz, Stefan Capitani, Francesco Berger, Helmuth Yazyev, Oleg V. Akrap, Ana 2020-09-08 Applying elastic deformation can tune a material’s physical properties locally and reversibly. Spatially modulated lattice deformation can create a bandgap gradient, favoring photogenerated charge separation and collection in optoelectronic devices. These advantages are hindered by the maximum elastic strain that a material can withstand before breaking. Nanomaterials derived by exfoliating transition metal dichalcogenides (TMDs) are an ideal playground for elastic deformation, as they can sustain large elastic strains, up to a few percent. However, exfoliable TMDs with highly strain-tunable properties have proven challenging for researchers to identify. We investigated 1T-ZrS2 and 1T-ZrSe2, exfoliable semiconductors with large bandgaps. Under compressive deformation, both TMDs dramatically change their physical properties. 1T-ZrSe2 undergoes a reversible transformation into an exotic three- dimensional lattice, with a semiconductor-to-metal transition. In ZrS2, the irreversible transformation between two different layered structures is accompanied by a sudden 14% bandgap reduction. These results establish that Zr-based TMDs are an optimal strain-tunable platform for spatially textured bandgaps, with a strong potential for novel optoelectronic devices and light harvesting. application/pdf https://folia.unifr.ch/global/documents/309107 https://folia.unifr.ch/documents/309107/files/akr_spt.pdf https://folia.unifr.ch/documents/309107/files/akr_spt_sm.pdf eng info:eu-repo/semantics/altIdentifier/doi/10.1021/acsmaterialslett.0c00252 info:eu-repo/semantics/openAccess License undefined ACS Materials Letters. - 2020, vol. 2, no. 9, p. 1115–1120 info:eu-repo/classification/udc/53 Structural phase transition and bandgap control through mechanical deformation in layered semiconductors 1T–ZrX2 (X = S, Se) http://purl.org/coar/resource_type/c_6501