Aggregation‐induced improvement of catalytic activity by inner‐aggregate electronic communication of metal‐fullerene‐based surfactants

authored by

Marius Kunkel, Stefan Bitter, Frank Sailer, Rainer F. Winter, Sebastian Polarz

Abstract

A paradigm for active constituents in (homogeneous) catalysis is that optimum performance requires maximum dispersion. Generally, aggregation results in a decline. This is a different case in supramolecular catalysis. A new concept based on surfactants equipped with functional heads is presented, which becomes a more active catalyst itself upon aggregation. The head group of the surfactants is composed of a diethylenetriamine-functionalized fullerene capable of coordinating to catalytically active metals like Co

^II. The improvement of catalytic properties upon aggregation is demonstrated via electrocatalytic water-splitting reaction as a model system. Detailed electrochemistry studies were performed at concentrations below and above the critical aggregation concentration (cac). While isolated surfactant molecules represent only moderately active catalysts, drastic improvement of efficiency in the hydrogen evolution (HER) as well as in the oxygen evolution reactions (OER) were detected, once vesicular structures have formed. Self-organization of the surfactants leads to an increase in turnover frequencies of up to 1300 % (HER). The strongly beneficial effect of aggregation arises from the favorable alignment of individual molecules, thus, facilitating intermolecular charge transfer processes in the vesicles.

Organisation(s)

Institute of Inorganic Chemistry

External Organisation(s)

University of Konstanz

Type

Article

Journal

CHEMCATCHEM

Volume

Pages

2726-2731

No. of pages

ISSN

1867-3880

Publication date

20.05.2020

Publication status

Published

Peer reviewed

Yes

ASJC Scopus subject areas

Catalysis, Inorganic Chemistry, Physical and Theoretical Chemistry, Organic Chemistry

Sustainable Development Goals

SDG 7 - Affordable and Clean Energy

Electronic version(s)

https://doi.org/10.1002/cctc.202000412 (Access: Open)