Premium
Electrically Induced Mixed Valence Increases the Conductivity of Copper Helical Metallopolymers
Author(s) -
Greenfield Jake L.,
Di Nuzzo Daniele,
Evans Emrys W.,
Senanayak Satyaprasad P.,
Schott Sam,
Deacon Jason T.,
Peugeot Adele,
Myers William K.,
Sirringhaus Henning,
Friend Richard H.,
Nitschke Jonathan R.
Publication year - 2021
Publication title -
advanced materials
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 10.707
H-Index - 527
eISSN - 1521-4095
pISSN - 0935-9648
DOI - 10.1002/adma.202100403
Subject(s) - copper , valence (chemistry) , materials science , nanoscopic scale , conductivity , chemical physics , electrical resistivity and conductivity , helix (gastropod) , atomic orbital , nanotechnology , crystallography , chemistry , electron , metallurgy , electrical engineering , physics , ecology , organic chemistry , engineering , quantum mechanics , snail , biology
Controlling the flow of electrical current at the nanoscale typically requires complex top‐down approaches. Here, a bottom‐up approach is employed to demonstrate resistive switching within molecular wires that consist of double‐helical metallopolymers and are constructed by self‐assembly. When the material is exposed to an electric field, it is determined that ≈25% of the copper atoms oxidize from Cu I to Cu II , without rupture of the polymer chain. The ability to sustain such a high level of oxidation is unprecedented in a copper‐based molecule: it is made possible here by the double helix compressing in order to satisfy the new coordination geometry required by Cu II . This mixed‐valence structure exhibits a 10 4 ‐fold increase in conductivity, which is projected to last on the order of years. The increase in conductivity is explained as being promoted by the creation, upon oxidation, of partly filledd z 2orbitals aligned along the mixed‐valence copper array; the long‐lasting nature of the change in conductivity is due to the structural rearrangement of the double‐helix, which poses an energetic barrier to re‐reduction. This work establishes helical metallopolymers as a new platform for controlling currents at the nanoscale.