Resistive switching in neem (Azadirachta indica) thin film for a cost-effective and washable biomemristor

The use of naturally produced biomaterials to develop various electronic devices addresses the long-term demand for bioelectronics. Natural biomaterialbased memristors have been proven for potential applications due to their sustainability, non-toxicity, ecological friendly, degradability, and biocompatibility. Hence, in this study, a biomaterials-inspired thin film was successfully synthesized from the leaf extract of the traditional medicinal tree, neem (Aza-dirachta indica) for prospective biomemristor applications that had not before been investigated. The electronic-grade thin film of neem exhibits up to 75% transparency over the majority of the visible spectrum. The various physiochemical, morphological, chemical and topographic characteristics of the deposited neem thin film have been investigated by XRD, FESEM, EDX, AFM and FTIR. Thermal stability of the neem film was further examined through thermogravimetric analysis. The fabricated FTO/Neem/Ag biomemristor demonstrated a reasonable bipolar, repeatable and non-volatile resistive switching along with a low yet stable resistance ratio between high and low resistance states, as well as acceptable endurance and retention characteristics. Using cyclic voltammetry, the physicochemical aspects were investigated further, and the underlying plausible memristive switching mechanisms were discussed. In addition, a feasible conduction mechanism is provided. Neem was also probed to demonstrate its transitory nature as an economical and ecofriendly non-volatile memory device.

Automated summary

The use of naturally produced biomaterials in bioelectronics addresses long-term demands. Natural biomaterial-based memristors have potential applications due to their sustainability, non-toxicity, degradability, and biocompatibility. In this study, a biomaterials-inspired thin film was successfully synthesized from neem leaf extract for biomemristor applications. The neem thin film showed high transparency and various physiochemical characteristics were investigated. The fabricated biomemristor demonstrated desirable resistance switching properties and a feasible conduction mechanism. Neem was also proven to be a temporary and eco-friendly non-volatile memory device.