Preparation Of Graphene Oxide-based Composite Memristive Materials And Research On Its Photoelectric Memristive Characteristics

The resistance of memristor can be adjusted by external electrical signals,and it has the advantages of simple device structure,fast operation speed and low power consumption for erasing and writing,etc.They show potential applications in the fields of information storage,logic operation and synaptic bionics.Compared with electric signal,optical signal has the advantages of fast speed,high bandwidth,no crosstalk,etc.In recent years,researchers have paid much attention to the development of photoelectric coupling memristor functions by using optical signal as a means of resistance modulation of memristor,such as,photoelectric logic operation,human brain vision bionics and simulated optogenetics,etc.Among various photoelectric memristor materials,graphene oxide(GO)has unique photoelectric properties.The oxygen ion migration in GO can induce the reversible transformation of carbon sp² and sp³hybridization state,and realize the regulation of material/device electrical properties.In this paper,TiO₂ and nitrogen containing quantum dots(NCQDs)materials with photocatalytic function were combined with GO,combining the photoreduction effect and electro-redox effect and then develop the composite photoelectric memristor materials and devices with digital or analog resistance characteristics.The photoelectric coupling mechanism of the two composites was studied to improve the memristor performance of the device.Based on two kinds of composite photoelectric memristor devices,a variety of functions have been developed,such as synaptic function bionics,visual system simulation,and photoelectric logic operation.The specific work contents are as follows:1.Al/TiO₂-GO/ITO composite memristor materials and devices with digital resistance properties were constructed by using TiO₂ and GO.And the photoreduction mechanism of TiO₂-GO composite film was studied through a series of characterization.Studied the effect of TiO₂ concentration on the resistance behavior of the device,to obtain the optimal concentration with stable digital resistance behavior.The UV radiation could eliminate the initialization process of the device and improve the resistance stability of the device.The size and proportion of sp² clusters in the films were controlled by adjusting the intensity and irradiation time of ultraviolet light,and the functions of image information perception and memory were simulated.Finally,the influence of the resistance performance and photoelectric memristor characteristics after bending were studied.2.The composite memristor materials and devices(Al/NCQDs-GO/ITO)with analog resistance properties were constructed by using NCQDs and GO.A variety of synaptic functions,including excitatory postsynaptic current(EPSC),double-pulse facilitation(PPF),and experience-dependent synaptic plasticity were simulated based on the analog resistive behavior(A-RS)of the device.Furthermore,the size and proportion of sp² clusters in the films were adjusted by adjusting the intensity and irradiation time of ultraviolet light,so as to flexibly control the initial state of the device.And the photoelectric cooperative control was developed to realize the light-on and electric-off function.The optoelectronic hybrid logic operation was developed and realized the commutative law of addition and commutative multiplication of decimal arithmetic.