Silver nanoparticles were synthesized by irradiating solutions, prepared by mixing AgNO3 and poly-vinyl alcohol (PVA), with 6 MeV electrons. The electron-irradiated solutions and the thin coatings cast from them were characterized using the ultraviolet–visible (UV–vis), x-ray diffraction (XRD), transmission electron microscopy (TEM) and scanning electron microscopy (SEM) techniques. During electron irradiation, the process of formation of the silver nanoparticles appeared to be initiated at an electron fluence of ∼2 × 1013 e cm−2. This was evidenced from the solution, which turned yellow and exhibited the characteristic plasmon absorption peak around 455 nm. Silver nanoparticles of different sizes in the range 60–10 nm, with a narrow size distribution, could be synthesized by varying the electron fluence from 2 × 1013 to 3 × 1015 e cm−2. Silver nanoparticles of sizes in the range 100–200 nm were also synthesized by irradiating an aqueous AgNO3 solution with 6 MeV electrons.

We report on the non-volatile resistive switching properties of epitaxial nickel oxide (NiO) nanostructures, 10-100 nm wide and up to 30 nm high grown on (001)-Nb:SrTiO3 substrates. Conducting-atomic force microscopy on individual nano-islands confirms prominent bipolar switching with a maximum ON/OFF ratio of ∼103 at a read voltage of ∼+0.4 V. This ratio is found to decrease with increasing height of the nanostructure. Linear fittings of I-V loops reveal that low and high resistance states follow Ohmic-conduction and Schottky-emission mechanism, respectively. The switching behavior (dependence on height) is attributed to the modulation of the carrier density at the nanostructure-substrate interface due to the applied electric field.

Resistive switching (RS) of (001) epitaxial multiferroic BiFeO3/La0.67Sr0.33MnO3/SrTiO3 heterostructures is investigated for varying lengths scales in both the thickness and lateral directions. Macroscale current–voltage analyses in conjunction with local conduction atomic force microscopy (CAFM) reveal that whilst both the local and global resistive states are strongly driven by polarization direction, the type of conduction mechanism is different for each distinct thickness regime. Electrode‐area dependent studies confirm the RS is dominated by an interface mechanism and not by filamentary formation. Furthermore, CAFM maps allow deconvolution of the roles played by domains and domain walls during the RS process. It is shown that the net polarization direction, and not domain walls, controls the conduction process. An interface mechanism based on barrier height and width alteration due to polarization reversal is proposed, and the role of electronic reconstruction at the interface is further investigated.

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