Limiting Molecular Twisting: Upgrading a Donor–Acceptor Dye to Drive H2 Evolution

Advanced Science, vol. 11, pp. e2403454

Abstract

Abstract The donor–acceptor (D–A) dye 4‐(bis‐4‐(5‐(2,2‐dicyano‐vinyl)‐thiophene‐2‐yl)‐phenyl‐amino)‐benzoic acid (P1) has been frequently used to functionalize NiO photocathodes and induce photoelectrochemical reduction of protons when coupled to a suitable catalyst. Photoinduced twisting of the P1 dye is steered on NiO by co‐adsorption of tetradecanoic acid (C14, myristic acid (MA)). Density Functional Theory and time‐resolved photoluminescence studies confirm that twisting lowers the energy levels of the photoexcited D–A dye. The apolar environment provided by the MA suppresses photoinduced D–A twisting, retards charge recombination following photoinduced charge separation between P1 and NiO, and provides a larger electrochemical potential increasing the photocurrent. Very interestingly, co‐adsorption of MA induces H2 evolution upon photoexcitation without the presence of an H2 evolution catalyst. Based on prior art, the formation of H2 is assigned to the dissolution of Ni2+, followed by reduction and re‐deposition of Ni nanoparticles acting as the catalytically active site. It propose that only excited P1 with suppressed twisting provides the sufficient electrochemical potential to induce deposition of Ni nanoparticles. The work illustrates the importance of understanding the effects of photoinduced intramolecular twisting and highlights the promise of designing twisting‐limited D–A dyes to create efficient solar fuel devices.

Authors 7

1. Kaijian Zhu

   University of Twente

   Affiliation as printed

   PhotoCatalytic Synthesis Group MESA+ Institute for Nanotechnology University of Twente P.O. Box 217 Enschede 7500 AE The Netherlands

   PhotoCatalytic Synthesis Group, MESA+ Institute for Nanotechnology, University of Twente, P.O. Box 217, Enschede, 7500 AE The Netherlands

2. Ainoa Paradelo Rodríguez

   University of Twente

   Affiliation as printed

   PhotoCatalytic Synthesis Group MESA+ Institute for Nanotechnology University of Twente P.O. Box 217 Enschede 7500 AE The Netherlands

   PhotoCatalytic Synthesis Group, MESA+ Institute for Nanotechnology, University of Twente, P.O. Box 217, Enschede, 7500 AE The Netherlands

3. Maria B. Brands

   University of Amsterdam

   Affiliation as printed

   van ‘t Hoff Institute for Molecular Sciences University of Amsterdam Science Park 904 Amsterdam 1098 XH The Netherlands

   van 't Hoff Institute for Molecular Sciences, University of Amsterdam, Science Park 904, Amsterdam, 1098 XH The Netherlands

4. Titus de Haas Aachen

   Leiden University

   Affiliation as printed

   Leiden Institute of Chemistry Leiden University P.O. Box 9502 Leiden 2300 RA The Netherlands

   Leiden Institute of Chemistry, Leiden University, P.O. Box 9502, Leiden, 2300 RA The Netherlands

5. Francesco Buda Aachen

   Leiden University

   Affiliation as printed

   Leiden Institute of Chemistry Leiden University P.O. Box 9502 Leiden 2300 RA The Netherlands

   Leiden Institute of Chemistry, Leiden University, P.O. Box 9502, Leiden, 2300 RA The Netherlands

6. Joost N. H. Reek

   University of Amsterdam

   Affiliation as printed

   van ‘t Hoff Institute for Molecular Sciences University of Amsterdam Science Park 904 Amsterdam 1098 XH The Netherlands

   van 't Hoff Institute for Molecular Sciences, University of Amsterdam, Science Park 904, Amsterdam, 1098 XH The Netherlands

7. Guido Mul

   University of Twente

   Affiliation as printed

   PhotoCatalytic Synthesis Group MESA+ Institute for Nanotechnology University of Twente P.O. Box 217 Enschede 7500 AE The Netherlands

   PhotoCatalytic Synthesis Group, MESA+ Institute for Nanotechnology, University of Twente, P.O. Box 217, Enschede, 7500 AE The Netherlands