Long-range electron transport in Prussian blue analog nanocrystals

Abstract

We report electron transport measurements through nano-scale devices consisting of 1 to 3 Prussian blue analog (PBA) nanoparticles connected between two electrodes. We compare two types of cubic nanoparticles, CsCoIIIFeII...

Electronic properties of single Prussian Blue Analog nanocrystals determined by conductive-AFM

“…We started analyzing the I ( v ) datasets with the SEL model. 25,26 In this model, the ET occurs through a single MO (here the HOMO according to our previous results) 24 located at an energy ε 0 below the Fermi energy of the electrodes. The MO is coupled (hybridized) to the electrodes, and these hybridizations are characterized by two coupling energies, Γ 1 and Γ 2 (see details in the ESI†).…”

Magnetic Hysteresis in a Monolayer of Oriented 6 nm CsNiCr Prussian Blue Analogue Nanocrystals

“…The bulk network of formula Cs I Ni II [Cr III (CN) 6 ]· n H 2 O crystallizes in a face-centered cubic (fcc) structure with the space group F 4̅3 m . − It orders ferromagnetically below 90 K as a result of a ferromagnetic exchange coupling between the Cr III ( S = 3/2) and Ni II ( S = 1) magnetic ions through the cyanide bridge . The 6 nm CsNiCr nanocrystals were prepared by spontaneous electrostatic stabilization in the absence of any stabilizing agent and fully characterized as already reported. , They have the same fcc structure as the bulk with a cell parameter of 10.5 Å; the distance between two atomic layers of a nanocrystal is half of the unit cell value (i.e., 5.25 Å). , They have the general formula Cs 0.85 Ni­[Cr­(CN) 6 ] 0.95 · n H 2 O. Part of the Cs + cations (0.35) occupy the tetrahedral sites of the fcc network, and the remaining (0.5) acts as countercations; the nanocrystals are therefore negatively charged.…”

“…Because the nanocrystals are stable in aqueous solution in the absence of any stabilizing agent, their assembly on different substrates can be carried out, − and was recently done on HOPG . HOPG is particularly adapted because, at ambient atmosphere, it has a hydrophilic surface due to the presence of a layer of water molecules on which it is possible to assemble the objects via hydrogen bonds. , The assembly process is carried out by immersing a freshly cleaved HOPG substrate for 3 h in an aqueous solution containing the nanocrystals.…”

“…Coordination networks of Prussian blue analogues (PBAs) and, more generally, cyanide-bridged systems are at the forefront in several research areas because of the versatility of their magnetic, optical, and conductivity properties. − Their unique physical behavior is mainly exploited when they are prepared as nanocrystals with applications in electrochromic devices, as efficient sensors and in nanomedicine. − The possibility to prepare the nanocrystals in aqueous solution without any stabilizing agent opened the route to (1) design core–shell objects where the shell and the size impact their magnetic anisotropy − or their photomagnetic response, , (2) tune the relaxation temperature and unravel the mechanism of the photoswitch of the CsCoFe­(CN) 6 photomagnetic objects by time-resolved spectroscopic studies in aqueous solution, and (3) assemble them on substrates as single and multilayers to probe the charge transport through a precise number of objects …”

Collective Magnetic Behavior of 11 nm Photo-Switchable CsCoFe Prussian Blue Analogue Nanocrystals: Effect of Dilution and Light Intensity

“…Because of their stability as isolated objects in water, they were used to unravel the mechanisms of charge transfer and spin crossover after light irradiation [10]. They were also deposited on graphite and their conductance was measured, showing a long range electron transport with relatively weak attenuation [11].…”