Premium
Molecular Triad Containing a TEMPO Catalyst Grafted on Mesoporous Indium Tin Oxide as a Photoelectrocatalytic Anode for Visible Light‐Driven Alcohol Oxidation
Author(s) -
Pati Palas Baran,
Abdellah Mohamed,
Diring Stéphane,
Hammarström Leif,
Odobel Fabrice
Publication year - 2021
Publication title -
chemsuschem
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.412
H-Index - 157
eISSN - 1864-564X
pISSN - 1864-5631
DOI - 10.1002/cssc.202100843
Subject(s) - catalysis , photochemistry , indium tin oxide , mesoporous material , alcohol oxidation , artificial photosynthesis , ruthenium , electron acceptor , electron transfer , chemistry , photocatalysis , photosensitizer , benzyl alcohol , inorganic chemistry , electrode , organic chemistry
Photoelectrochemical cells based on semiconductors are among the most studied methods of artificial photosynthesis. This study concerns the immobilization, on a mesoporous conducting indium tin oxide electrode (nano‐ITO), of a molecular triad (NDADI−P−Ru‐TEMPO) composed of a ruthenium tris‐bipyridine complex (Ru) as photosensitizer, connected at one end to 2,2,6,6‐tetramethyl‐1‐piperidine N‐oxyl (TEMPO) as alcohol oxidation catalyst and at the other end to the electron acceptor naphthalenedicarboxyanhydride dicarboximide (NDADI). Light irradiation of NDADI−P−Ru‐TEMPO grafted to nano‐ITO in a pH 10 carbonate buffer effects selective oxidation of para ‐methoxybenzyl alcohol (MeO−BA) to para ‐methoxybenzaldehyde with a TON of approximately 150 after 1 h of photolysis at a bias of 0.4 V vs. SCE. The faradaic efficiency is found to be of 80±5 %. The photophysical study indicates that photoinduced electron transfer from the Ru complex to NDADI is a slow process and must compete with direct electron injection into ITO to have a better performing system. This work sheds light on some of the important ways to design more efficient molecular systems for the preparation of photoelectrocatalytic cells based on catalyst‐dye‐acceptor arrays immobilized on conducting electrodes.