The photothermal effect in mofs

• Autores: Jordi Espín Martí
• Directores de la Tesis: Daniel Maspoch Comamala (dir. tes.), Inhar Imaz (codir. tes.), Félix Busqué Sánchez (tut. tes.)
• Lectura: En la Universitat Autònoma de Barcelona ( España ) en 2018
• Idioma: español
• Tribunal Calificador de la Tesis: Félix Zamora Abenades (presid.), Jordi Hernando Campos (secret.), José Puigmarti Luis (voc.)
• Programa de doctorado: Programa de Doctorado en Química por la Universidad Autónoma de Barcelona
• Materias:
  • Química
    • Química inorgánica
• Enlaces
  • Tesis en acceso abierto en:  TESEO  TDX 
• Resumen

  • This Thesis is devoted to the study of the interaction of light with coordination polymers (CPs) and metal-organic frameworks (MOFs). Two strategies have been followed to accomplish this objective. The first approach consisted on the study of the photothermal effect observed in different families of MOFs, which exhibited local heating upon UV-Vis irradiation. This photothermal effect has been proved useful for the activation and the covalent-post synthetic modification (CPSM) of MOFs. The second strategy was based on the synthesis of CPs following a ligand design approach using light-harvesting MeBIP-based and Ru2+-terpyridine metalloligands.

    Chapter 1 encloses a general introduction to CPs and MOFs, containing a historical overview of their evolution as well as some of their multiple applications. In this sense, applications arisen from the use of light as an external stimulus in MOFs have been described. Then, in Chapter 2, we have summarized the main objective of this Thesis and detailed the specific sub goals.

    Chapter 3 introduces the fundamentals of the light-to-heat conversion in different materials. Some examples of MOFs composites, in which inorganic nanoparticles exhibit photothermal properties, are reviewed. Moreover, a summary of some of the most common methods for removing guest molecules from MOF pores (activation process) is included. In this chapter, we demonstrate that some MOFs show a pronounced photothermal effect and that this effect can be used to activate them by removing the solvent molecules after their irradiation with a UV-Vis lamp for short periods of time.

    In Chapter 4, post-synthetic modification (PSM) of MOFs is reviewed based on the different existing methods and interactions between the framework and the desired reagents. This chapter proposes a new PSM based on the generation of local heat upon MOF irradiation. Based on this method, solvent-free CPSM of amino-tagged MOFs (UiO-66-NH2 and MIL-101-NH2(Al)) was achieved by mixing them with solid reagents (maleic and benzoic anhydrides), and subsequently irradiating the mixture with a UV-Vis light. The photothermal effect exhibited by the MOFs provokes the melting of the reagent leading to its attachment to the MOF structures through amide bonds formation.

    In Chapter 5, the light-harvesting and photothermal properties of some organometallic complexes are exemplified. The beneficial strategy of using these moieties as building units in CPs and MOFs for enhancing their performance is described. The strategy followed in this chapter consisted on a two-step synthesis, which first required the synthesis of light-harvesting metalloligands with available coordinating groups, and a further linkage of these metalloligands with secondary metal ions to obtain extended CPs. In this chapter, three different CPs made of Ru2+-terpyridine-based metalloligands and Co2+ and Zr4+ ions have been synthesised and their photothermal properties studied.