title: Aqueous Exfoliation of Transition Metal Dichalcogenides Assisted by DNA/RNA Nucleotides: Catalytically Active and Biocompatible Nanosheets Stabilized by Acid-Base Interactions.
abstract: The exfoliation and colloidal stabilization of layered transition metal dichalcogenides (TMDs) in an aqueous medium using functional biomolecules as dispersing agents have a number of potential benefits toward the production and practical use of the corresponding two-dimensional materials, but such a strategy has so far remained underexplored. Here, we report that DNA and RNA nucleotides are highly efficient dispersants in the preparation of stable aqueous suspensions of MoS2and other TMD nanosheets at significant concentrations (up to 5-10 mg mL-1). Unlike the case of common surfactants, for which adsorption on 2D materials is generally based on weak dispersive forces, the exceptional colloidal stability of the TMD flakes was shown to rely on the presence of relatively strong, specific interactions of Lewis acid-base type between the DNA/RNA nucleotide molecules and the flakes. Moreover, the nucleotide-stabilized MoS2nanosheets were shown to be efficient catalysts in the reduction of nitroarenes (4-nitrophenol and 4-nitroaniline), thus constituting an attractive alternative to the use of expensive heterogeneous catalysts based on noble metals, and exhibited an electrocatalytic activity toward the hydrogen evolution reaction that was not impaired by the possible presence of nucleotide molecules adsorbed on their active sites. The biocompatibility of these materials was also demonstrated on the basis of cell proliferation and viability assays. Overall, the present work opens new vistas on the colloidal stabilization of 2D materials based on specific interactions that could be useful toward different practical applications.
authors.affiliation: Instituto Nacional del Carbón , INCAR-CSIC, Apartado 73, 33080 Oviedo, Spain.
authors.forename: Miguel
authors.initials: M
authors.lastname: Ayán-Varela
authors.affiliation: Instituto Nacional del Carbón , INCAR-CSIC, Apartado 73, 33080 Oviedo, Spain.
authors.forename: Óscar
authors.initials: Ó
authors.lastname: Pérez-Vidal
authors.affiliation: Instituto Nacional del Carbón , INCAR-CSIC, Apartado 73, 33080 Oviedo, Spain.
authors.forename: Juan I
authors.initials: JI
authors.lastname: Paredes
authors.affiliation: Instituto Nacional del Carbón , INCAR-CSIC, Apartado 73, 33080 Oviedo, Spain.
authors.forename: José M
authors.initials: JM
authors.lastname: Munuera
authors.affiliation: Instituto Nacional del Carbón , INCAR-CSIC, Apartado 73, 33080 Oviedo, Spain.
authors.forename: Silvia
authors.identifier: http://orcid.org/0000-0002-5832-9971
authors.initials: S
authors.lastname: Villar-Rodil
authors.affiliation: Instituto de Microelectrónica de Barcelona , IMB-CNM (CSIC), Campus UAB, 08193 Bellaterra, Barcelona, Spain.
authors.forename: María
authors.initials: M
authors.lastname: Díaz-González
authors.affiliation: Instituto de Microelectrónica de Barcelona , IMB-CNM (CSIC), Campus UAB, 08193 Bellaterra, Barcelona, Spain.
authors.forename: César
authors.initials: C
authors.lastname: Fernández-Sánchez
authors.affiliation: CESAM & Department of Biology, University of Aveiro , Campus Universitario de Santiago, 3810-193 Aveiro, Portugal.
authors.forename: Virgilia S
authors.initials: VS
authors.lastname: Silva
authors.affiliation: TEMA-NRG, Mechanical Engineering Department & CICECO-Aveiro Institute of Materials, Department of Chemistry, University of Aveiro , Campus Universitario de Santiago, 3810-193 Aveiro, Portugal.
authors.forename: Mónica
authors.initials: M
authors.lastname: Cicuéndez
authors.affiliation: TEMA-NRG, Mechanical Engineering Department, University of Aveiro , Campus Universitario de Santiago, 3810-193 Aveiro, Portugal.
authors.forename: Mercedes
authors.initials: M
authors.lastname: Vila
authors.affiliation: Instituto Nacional del Carbón , INCAR-CSIC, Apartado 73, 33080 Oviedo, Spain.
authors.forename: Amelia
authors.initials: A
authors.lastname: Martínez-Alonso
authors.affiliation: Instituto Nacional del Carbón , INCAR-CSIC, Apartado 73, 33080 Oviedo, Spain.
authors.forename: Juan M D
authors.initials: JM
authors.lastname: Tascón
mesh_terms: D004247:DNA; D009711:Nucleotides; D012313:RNA; D028561:Transition Elements / Q000737:chemistry*; D014867:Water
chemical_list: D009711:Nucleotides; D028561:Transition Elements; D014867:Water; D012313:RNA; D004247:DNA
keywords: DNA; catalyst; colloidal dispersion; hydrogen evolution reaction (HER); nucleotide; transition metal dichalcogenides (TMDs); two-dimensional (2D) material