Biocompatible, Flexible, and High-Performance Nanowelded Silver Nanowires on Silk Fibroin for Transparent Conducting Electrodes toward Biomemristor Application

Abstract

This paper demonstrates a facile methodology for fusing silver nanowires (AgNWs) at the nanoscale using a simple, cost-effective UV-ozone treatment. The fusing process not only resulted in interesting morphologies but also reduced the sheet resistance from 100 to 15 Ω/sq. The process optimization ensued in the fusion of AgNWs at the edges with different bending angles that lie between 100 and 140°. The mechanism behind the fusing was elucidated primarily using high-resolution transmission electron microscopy analysis. The optimized process was replicated on top of a silk−poly(vinyl)alcohol (S−PVA) composite that is proven to be thermally stable, flexible, transparent, and biocompatible. This unique combination of fused AgNWs on top of S−PVA is a viable, cost-effective, and scalable prototype for flexible transparent conducting electrodes (FTCEs). A flexible biomemristor was fabricated using ZnO nanoparticles as an active layer and gold and AgNWs as top and bottom electrodes, respectively. The fabricated biomemristor on S−PVA exhibited oxygen vacancy-based R S characteristics at a lower set/reset voltage of +0.25 V/−1 V with an excellent R OFF /R ON ratio of 3.5 × 10 3 , higher switching endurance of 500 cycles, and stable data retention of greater than 10 4 seconds. The strategy outlined here provides a simple, facile, and best optimized solution for the preparation of high-performance and biocompatible FTCEs for the next-generation wearable optoelectronic and biomedical devices.

Phytochemical-Mediated Green Synthesis of Ag Nanowires and Fabrication of Highly Flexible, Biocompatible, and Antibiofouling Conductive Films

“…Among all metals, Ag nanowires (AgNWs) are particularly interesting because Ag has the highest electrical (6.39107 S m –1 ) and thermal (429 W m –1 K –1 ) conductivity . Films made of interconnected AgNWs in polymer composites are the most promising next-generation transparent flexible electrodes to replace the fragile and expensive indium tin oxide (ITO) in photoelectric devices, flexible fuel cells, energy devices, and sensors. − In addition, good biocompatibility and broad-spectrum antimicrobial activity make AgNWs suitable to fabricate epidermal and implantable bioelectronics in the health monitoring areas. − …”

All-Solution-Processed Polythiophene/Carbon Nanotube Nanocomposites Integrated on Biocompatible Silk Fibroin Substrates for Wearable Thermoelectric Generators

“…In addition to thermoelectric materials and electrodes, substrates are another concern for fabricating flexible devices. Compared to conventional elastomeric polymer thin films, such as polyimide and polyethylene terephthalate, , silk fibroin films offer more appealing platforms for developing biocompatible and implantable supported bioelectronics. − Silk fibroin biopolymers offer excellent breathability and comfort on the human skin, allowing for intimate contact with curved surfaces without degrading over time. , Additionally, petrochemical-based substrates are expected to be replaced by natural biopolymers explored in electronic devices owing to the increased awareness of environmental and sustainability issues. , To date, there has been no report on the fabrication of biocompatible substrated thermoelectric generators for wearable devices using all-solution fabrication techniques.…”

One-step fabrication of highly stable, durable, adhesion enhanced, flexible, transparent conducting films based on silver nanowires and neutralized PEDOT:PSS

“…At present, indium tin oxide (ITO) TCEs are most commonly used in electronic applications owing to their higher conductivity and optical transmittance. However, the usage of ITO in flexible electronics is limited due to drawbacks such as inflexibility (highly brittle), high-temperature fabrication process, higher costs for production, and shortage of rare earth metals [21][22][23][24][25][26][27][28]. Due to the above shortcomings, the production of large-size flexible and stretchable devices using ITO is difficult.…”

“…However, the use of ITO in flexible electronics is limited due to drawbacks such as inflexibility (highly brittle), a high-temperature fabrication process, higher costs for production, and shortage of rare earth metals. [21][22][23][24][25][26][27][28] Due to the above shortcomings, the production of large-size flexible and bendable devices using ITO is difficult. Hence it is very essential to find alternative materials to ITO with easy TCE fabrication processes and flexibility and bendability characteristics.…”