Multibranched Calix[4]arene‐Based Sensitizers for Efficient Photocatalytic Hydrogen Production. Issue 2 (16th December 2020)

• Record Type: Journal Article
• Authors: Manfredi, Norberto; Decavoli, Cristina; Boldrini, Chiara Liliana; Dolla, Tarekegn Heliso; Faroldi, Federica; Sansone, Francesco; Montini, Tiziano; Baldini, Laura; Fornasiero, Paolo; Abbotto, Alessandro
• Is Part Of: European journal of organic chemistry. Issue 2(2021)
• Page Start: 284
• Page End: 288
• Publication Date: 2020-12-16
• Subjects: Calixarenes -- Dyes/Pigments -- Hydrogen -- Photocatalysis -- Sensitizers; Chemistry, Organic -- Periodicals; Organic compounds -- Synthesis -- Periodicals; Bioorganic chemistry -- Periodicals; Chemistry, Physical organic -- Periodicals; 547
• DOI: 10.1002/ejoc.202001296
• Languages: English
• ISSNs: 1434-193X

Abstract

Abstract: In the field of direct production of hydrogen from solar energy and water, photocatalytic methods hold great potential especially when metal‐free molecular components are preferred. In this work, we have developed a new class of calix[4]arene‐based molecular photosensitizers to be used as antenna systems in the photocatalytic production of hydrogen. The structure of the dyes has a typical donor‐π‐acceptor molecular architecture where a calix[4]arene scaffold is used as an embedded donor. The new materials have been fully characterized in their optical, electrochemical, and photocatalytic properties. The properties conferred by the calix[4]arene donor afforded twice larger performances compared to the corresponding linear system though showing similar quantitative optical properties. The new molecular design paves the way to a new strategy for photocatalytic hydrogen production where the calix[4]arene scaffold can afford more efficient systems and can offer the potential for host‐guest supramolecular effects. Abstract : A new series of calix[4]arene‐based push‐pull dyes have been synthesized, fully characterized, and used in photocatalytic hydrogen production. Among the new dyes, the bithiophene‐based π spacer derivative showed superior photoactivity. The incorporation of the calixarene aromatic donor unit into the dye structure provides hydrogen generation efficiencies that are twice as high as the corresponding linear analog, although it exhibits similar quantitative light‐harvesting properties.