Spin Transition in Arrays of Gold Nanoparticles and Spin Crossover Molecules
Artikel i vetenskaplig tidskrift, 2015

We investigate if the functionality of spin crossover molecules is preserved when they are assembled into an interfacial device structure. Specifically, we prepare and investigate gold nanoparticle arrays, into which room-temperature spin crossover molecules are introduced, more precisely, [Fe(AcS-BPP)(2)](ClO4)(2), where AcS-BPP = (S)-(4-{[2,6-(dipyrazol-1-yl)pyrid-4-yl]ethynyl}phenyl)ethanethioate (in short, Fe(S-BPP)(2)). We combine three complementary experiments to characterize the molecule-nanoparticle structure in detail. Temperature-dependent Raman measurements provide direct evidence for a (partial) spin transition in the Fe(S-BPP)(2)-based arrays. This transition is qualitatively confirmed by magnetization measurements. Finally, charge transport measurements on the Fe(S-BPP)(2)-gold nanoparticle devices reveal a minimum in device resistance versus temperature, R(T), curves around 260-290 K. This is in contrast to similar networks containing passive molecules only that show monotonically decreasing R(T) characteristics. Backed by density functional theory calculations on single molecular conductance values for both spin states, we propose to relate the resistance minimum in R(T) to a spin transition under the hypothesis that (1) the molecular resistance of the high spin state is larger than that of the low spin state and (2) transport in the array is governed by a percolation model.

spin crossover molecules

molecular charge transport devices

self-assembly

gold nanoparticles

Författare

E. J. Devid

Universiteit Leiden

P. N. Martinho

Universidade de Lisboa

Karlsruher Institut für Technologie (KIT)

Venkata Kamalakar Mutta

Chalmers, Mikroteknologi och nanovetenskap (MC2), Kvantkomponentfysik

I. Salitros

Slovak University of Technology Bratislava

Karlsruher Institut für Technologie (KIT)

U. Prendergast

Dublin City University

J. F. Dayen

Universite de Strasbourg

V. Meded

Karlsruher Institut für Technologie (KIT)

T. Lemma

Dublin City University

R. Gonzalez-Prieto

Karlsruher Institut für Technologie (KIT)

Universidad Autonoma de Madrid (UAM)

F. Evers

Karlsruher Institut für Technologie (KIT)

T. E. Keyes

Dublin City University

M. Ruben

Universite de Strasbourg

Karlsruher Institut für Technologie (KIT)

B. Doudin

Universite de Strasbourg

S. J. van der Molen

Universiteit Leiden

ACS Nano

1936-0851 (ISSN) 1936-086X (eISSN)

Vol. 9 4 4496-4507

Ämneskategorier

Nanoteknik

DOI

10.1021/acsnano.5b01103