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A one‐selector one resistor (1S1R) array formed of a selector and resistive random access memory (RRAM) is an important way to achieve high‐density storage and neuromorphic computing. However, the low durability and poor consistency of the selector limit its practical application. The fabrication of a selector based on egg albumen (EA) is reported in this paper. The device exhibits excellent bidirectional threshold switching characteristics, including a low leakage current (10−7 A), a high ON/OFF current ratio (106), and good endurance (>700 days). It is used as a selector to form a 1S1R unit in combination with an EA‐based RRAM to effectively solve the leakage current in a crossbar array. A feasible solution is provided for the realization of a protein‐based 1S1R array to achieve high‐density storage. The 1S1R unit shows characteristics similar to those of synapses in the human brain under impulse excitation and has great potential in simulating the human brain for neuromorphic calculations.) [ABSTRACT FROM AUTHOR]

Al/PMMA/SY : GQDs/PMMA/ITO devices with multilayer structures were fabricated by imbedding PMMA at both ends of soybean (SY) and graphene quantum dot (GQD) dielectric layers, which not only improved the stability of the devices but also reduced the threshold voltage and power consumption. A single unit of the device can complete the logical "AND" and "OR" operations to realize the memory calculation, which provides a new way to overcome the memory bottleneck of computer systems. [ABSTRACT FROM AUTHOR]

Most current resistive memory has the problems of high and unstable threshold voltages and high device misread rates caused by low current switching ratios. To address these problems, an Al/poly(methyl methacrylate) (PMMA)/silkworm hemolymph:gold nanoparticles/PMMA/indium tin oxide memory device is fabricated by adding PMMA layers above and below the active layer. The device not only has stable bipolar switching characteristics with a high ON/OFF current ratio but also has a lower and more stable threshold voltage. Potentiation, depression, and spike‐time‐dependent plasticity at biological synapses are realized using this device. The device is successfully fabricated on a flexible substrate, and the device can still maintain a stable working state after 104 bending cycles. This research opens a new door for the future realization of artificial synapses in neural network hardware. [ABSTRACT FROM AUTHOR]

Organic-resistance random access memory has high application potential in the field of next-generation green nonvolatile memory. Because of their biocompatibility and environmental friendliness, natural biomaterials are suitable for the fabrication of biodegradable and physically transient resistive switching memory devices. A flexible memory device with physically transient properties was fabricated with silver ions and egg albumen composites as active layers, which exhibited characteristics of write-once-read-many-times (WORM), and the incorporation of silver ions improved the ON/OFF current ratio of the device. The device can not only complete the logical operations of "AND gate" and "OR gate", but its active layer film can also be dissolved in deionized water, indicating that it has the characteristics of physical transients. This biocompatible memory device is a strong candidate for a memory element for the construction of transient electronic systems. [ABSTRACT FROM AUTHOR]

Three novel conjugated polymers based on 9,9′‐dioctylfluorene unit and isoindolo[2,1‐a]benzimidazol‐11‐one with different fluorine substituents (0, 2 and 4) were synthesized. PLED and resistive memory devices based on these polymers were prepared consequently. PLED based on four‐fluorinated polymer showed the highest maximum brightness of 3192 cd m−2 with almost 5‐fold increase of current efficiency 8‐fold increase of external quantum efficiency compared to that of the other two, and all the PLEDs exhibited good emission stability with no noticeable change of electroluminescence even under high voltage of 10 V. The memory device of doubly‐fluorinated polymer exhibited ternary flash behavior with threshold voltages below −2.5 V, while device of four‐fluorinated polymer possessed ON/OFF current ratio above 104. Impact of fluorine substitutions on the performance of devices were briefly investigated. The results revealed that the improvement of device performance might not scale with the increasing number of fluorine substitutions, and the four‐fluorine‐substituted polymer and doubly‐fluorinated polymer could be encouraging materials for applications of PLED and resistive memory device and worth of further design of other new polymer systems. [ABSTRACT FROM AUTHOR]

In this paper, a tuneable multilevel data storage bioresistive memory device is prepared from a composite of multiwalled carbon nanotubes (MWCNTs) and egg albumen (EA). By changing the concentration of MWCNTs incorporated into the egg albumen film, the switching current ratio of aluminium/egg albumen:multiwalled carbon nanotubes/indium tin oxide (Al/EA:MWCNT/ITO) for resistive random access memory increases as the concentration of MWCNTs decreases. The device can achieve continuous bipolar switching that is repeated 100 times per cell with stable resistance for 104 s and a clear storage window under 2.5 × 104 continuous pulses. Changing the current limit of the device to obtain low-state resistance values of different states achieves multivalue storage. The mechanism of conduction can be explained by the oxygen vacancies and the smaller number of iron atoms that are working together to form and fracture conductive filaments. The device is nonvolatile and stable for use in rewritable memory due to the adjustable switch ratio, adjustable voltage, and nanometre size, and it can be integrated into circuits with different power consumption requirements. Therefore, it has broad application prospects in the fields of data storage and neural networks. [ABSTRACT FROM AUTHOR]

In this study, a flexible bioresistive memory with an aluminum/tussah hemolymph/indium tin oxide/polyethylene terephthalate structure is fabricated by using a natural biological material, tussah hemolymph (TH), as the active layer. When different compliance currents (Icc) are applied to the device, it exhibits different resistance characteristics. When 1 mA is applied in the positive voltage range and 100 mA is applied in the negative voltage range, the device exhibits bipolar resistive switching behavior. Additionally, when 1 mA is applied in both the positive- and negative-voltage ranges, the device exhibits write-once-read-many-times (WORM) characteristics. The device has good endurance, with a retention time exceeding 104 s. After 104 bending cycles, the electrical characteristics remain constant. This memory device can be applied for "AND" and "OR" logic operations in programmable logic circuits. The prepared flexible and transparent biomemristor made of pure natural TH provides a promising new approach for realizing environmentally friendly and biocompatible flexible memory, nerve synapses, and wearable electronic devices. [ABSTRACT FROM AUTHOR]

Resistive switching memory devices are strong candidates for next-generation data storage devices. Biological memristors made from renewable natural biomaterials are very promising due to their biocompatibility, biodegradability, and ecological benignity. In this study, a nonvolatile memristor was fabricated using the body fluid of Bombyx mori as the dielectric layer. The developed Al/Bombyx mori body fluid film/indium tin oxide (ITO) biomemristor exhibited bipolar resistive switching characteristics with a maximum on/off current ratio greater than 104. The device showed a retention time of more than 1 × 104 s without any signs of deterioration, thus proving its good stability and reliability. The resistive switching behavior of the Al/Bombyx mori body fluid film/ITO biological memristor is driven by the formation and breakage of conductive filaments formed by the migration of oxygen ions. This study confirms that Bombyx mori body fluid, a 100% natural, inexpensive, and abundant material, is a potential candidate as a nonvolatile biomemristor material with broad application prospects. [ABSTRACT FROM AUTHOR]

• A resistive random access memory with biodegradability and biocompatibility is fabricated. • The device has a high ON/OFF current ratio of 5.22 × 105. • The single memory cell of this device has multilevel (8 levels, 3 bits) data storage capacity. • The device can simulate the potentiation and depression of synapses. [Display omitted] In this study, silkworm body fluid (SF), a natural biological material, was compounded with gold nanoparticles (Au NPs) to form a dielectric layer, and the biodegradable resistive random access memory (RRAM) of Al/SF:Au NPs/indium tin oxide (ITO) was fabricated. The experimental results show that embedding Au NPs increases the ON/OFF current ratio of the Al/SF:Au NPs/ITO device to 5.22 × 105. The resistances of the high resistance and low resistance states of the Al/SF:Au NPs/ITO device are well maintained, reaching 104 s. These devices can be easily fabricated using solution-based processes on substrates at room temperature, and they have reliable data storage capability. Because the compliance current is controlled, a single memory cell of a device based on SF:Au NPs has a multilevel (8 levels, 3 bits) resistance state for high-density storage, enabling multilevel data storage. Application of the device in simulating neurobehavior is further explored, and potentiation and depression of the simulated synapse can be achieved by applying pulses to the device. SF:Au NP-based RRAM shows great potential in multilevel data storage and neuromorphic computing. RRAM based on natural biomaterials has the advantages of biocompatibility, biodegradability and low cost, and it provides an important step toward the future development of bioelectronic devices. [ABSTRACT FROM AUTHOR]