Enhanced efficiency for the visible-light photocatalytic hydrogen generation of ruthenium tris(2,2’-bipyridyl)/methyl viologen system by the presence of cucurbit[n]urils

• Type: Article in International Scientific Journal
• Date: 2009

Authors

Cláudia Gomes Silva (Author) FEUP; Maykel de Miguel (Author) Other; Belén Ferrer (Author) Other; Mercedes Álvaro (Author) Other; Hermenegildo García (Author) Other

Journal

Title: Photochemical & Photobiological Sciences

Pages: 1650-1654

ISSN: 1474-905X

Publisher: Springer Nature

Indexing

ISI Web of Science

Scopus

Scientific classification

FOS: Engineering and technology > Chemical engineering

Other information

DOI: 10.1039/B9PP00063A

Abstract (EN): Cucurbiturils are cyclic oligomers of glycoluril units whose molecular shape defines an internal hollow space accessible through carbonyl portals. It is known that methyl viologen forms strong host–guest complexes with CB[7] and CB[8]. In the latter case even a dimer can be hosted inside CB[8]. Classical solution systems for visible light H2 generation use methyl viologen as an electron relay. In this work we have found that the efficiency for H2 generation of the photocatalytic system comprising EDTA–ruthenium tris(2,2′-bipyridyl)–methyl viologen–Pt increases when cucurbiturils are present in the solution. The enhancement follows the order CB[6] < CB[7] < CB[8]. By means of laser flash photolysis we have established that this efficiency increase arises from the combination of an increase in the relative quantum yield of charge separation (higher efficiency in the formation of MV˙+) and a decrease of MV˙+ lifetime.

Language: English

Type (Professor's evaluation): Scientific