The Study On Electric-Field-Controlled Structures And Transport Properties Of MoO₃ And Gd₂O₃ Films

In iontronics,theelectronic properties and the functionality of the materials are achieved by ionic motion and arrangement,which makes the materials have promising applications in many fields such as information storage,emulation of artificialsynapses and intelligent display.In this paper,we choseboth MoO₃ with wealthy structuresand Gd₂O₃with a high oxygen mobility as the objects,constructed three kinds of devices including the ionic-liquid gating-induced MoO₃ device,the MoO₃ film grown on the Li⁺ions conductive ceramics,and resistive switching devices with MoO₃ and Gd₂O₃materials as matrices.Theelectric-field-controlled structures,electrical,opticaland magnetic properties of MoO₃ and Gd₂O₃ materials were explored.And the related mechanisms werediscussed.?1?Proticionic-liquid gated?-MoO₃films.The as-deposited?-MoO₃film is transparent.Its resistance is too high?more than 1.0×10⁸ Ohm?to be measured;After ionic-liquid gating at 3.5V,it became blue and its resistance fell rapidly off to 2.25×10³?;After the gated film was placed in air for 48 hours,itvaried from blue to transparentand its resistance is increased.The phenomena may be because H⁺ions in the proticionic liquid are inserted into?-MoO₃ during the gating process,and the inserted H⁺are extracted from the MoO₃film when it was placed in the air.?2?Electric-field-controlled?-MoO₃ films grownon the Li⁺ions conductive ceramics.The as-deposited?-MoO₃film is transparent.Its resistance is too high to be measured;Itbecame blue and its resistance is decreased after the film was modulated by electric field of+3.5 V.The color and resistance of the induced sample did not show significant changes even after 2 months.The phenomena may be because Li⁺ions in the Li⁺ions conductive ceramics are inserted into?-MoO₃during the electric field modulation.Whereas,the inserted H⁺ionsare difficult to extract from MoO₃ film.?3?Resistive switching properties of?-MoO₃ and Gd₂O₃ films.They both exhibit bipolar resistive switching properties.And they exhibits metallic conductivity at low resistive state,which may result from the migration of oxygen ions.In MoO₃ films,the migration of O^2-ions may reduce Mo ions from+6 valence to lower one.As this,some conductive regionssuch as MoO₂ or some Mo-rich may be formed.In Gd₂O₃films,the migration of O^2-ions may lead to the reduction of some Gd³⁺ions into metallic ferromagnetic Gd atoms,which leads to the occurrence of the resistance switching effectaccompanied with a change of magnetization.In conclusion,the microstructures,transport,optical and magnetic properties of MoO₃ and Gd₂O₃materials are modulated by electrical-controlled the interaction of H⁺and Li⁺ions and the extractionof O^2-ions.This study can provide novel clues and significant references for future research and application of information storage,emulation of artificialsynapses,and intelligent display in the storage and simulation processes.