Memristive properties of hexagonal WO3 nanowires induced by oxygen vacancy migration

Abstract

Tungsten trioxide (WO3) is always oxygen-deficient or non-stoichiometric under atmospheric conditions. Positively charged oxygen vacancies prefer to drift as well as electrons when the electric field is strong enough, which will alter the distribution of oxygen vacancies and then endow WO3 with memristive properties. In Au/WO3 nanowire/Au sandwich structures with two ohmic contacts, the axial distribution of oxygen vacancies and then the electrical transport properties can be more easily modulated by bias voltage. The threshold electric field for oxygen vacancy drifting in single-crystal hexagonal WO3 nanowire is about 106 V/m, one order of magnitude less than that in its granular film. At elevated temperatures, the oxygen vacancy drifts and then the memristive effect can be enhanced remarkably. When the two metallic contacts are asymmetric, the WO3 nanowire devices even demonstrate good rectifying characteristic at elevated temperatures. Based on the drift of oxygen vacancies, nanoelectronic devices such as memristor, rectifier, and two-terminal resistive random access memory can be fabricated on individual WO3 nanowires.

Recent Developments and Perspectives for Memristive Devices Based on Metal Oxide Nanowires

“…The drift of oxygen vacancies was considered responsible for memristive properties with hysteretic I-V characteristics also in hexagonal WO 3 NWs, as observed by He et al [167] Moreover, it Adv. Electron.…”

“…[167] The initial amount of oxygen vacancies and defects resulting from the synthesis can strongly impact the switching parameters and performances, thus the growth conditions play a crucial role for the realization of NW-based resistive switching devices. [167] The initial amount of oxygen vacancies and defects resulting from the synthesis can strongly impact the switching parameters and performances, thus the growth conditions play a crucial role for the realization of NW-based resistive switching devices.…”

Polymer/carbon nanofillers films fabricated by latex technology

“…The significantly lower percolation threshold of the studied systems is attributed to the high CNT dispersion level in the resulting nanocomposite layers, which is found to facilitate the formation of a conducting network at lower filler loadings. [48] It should also be noted that the percolation value achieved in this work is considerably lower compared with other polymer/MWNT nanocomposites reported in the literature, [49][50][51][52][53][54][55][56] demonstrating the superiority of the developed fabrication approach compared with the previous methods. Table S1 (Supporting information) summarizes the percolation threshold values reported for polymer/CNT nanocomposites fabricated via the latex-based approach, demonstrating that the percolation threshold of the studied polyacrylate/MWNT layers is low in comparison with the literature reported values.…”

Development of Ag/ZnO/FTO thin film memristor using aqueous chemical route

“…The device resistance switches from Low Resistance State (LRS) to High Resistance state (HRS) and High Resistance State (HRS) to Low Resistance State (LRS) i.e. RESET to SET and vice versa depending on the applied external bias, in other words, it will memorize the last resistance state due to fact that instantaneous resistance will be uniquely defined by either applied current or voltage [33]. From the figure it is seen that resistance will be increased if current flows in one direction and reduced if it flows in another direction.…”