Researchers Discover Unlikely Materials for Advanced Memristors
A team of researchers from The Ohio State University recently unveiled innovative findings in the realm of electronics, demonstrating that unexpected materials can serve as effective memristors. Memristors are essential components in computing, capable of both processing and storing data by recalling past electrical states. The study highlights the potential of organic substances such as shiitake mushrooms, honey, and even human blood to function as viable alternatives to conventional memristor materials.
Shiitake Mushrooms as Memristors
While exploring the electrical properties of fungi, lead researcher John LaRocco and his team discovered that shiitake mushrooms could function similarly to traditional memristors. The researchers cultivated nine samples of shiitake under optimal conditions, providing them with a diet of farro, wheat, and hay. Once matured, the mushrooms were dried and rehydrated to enhance their conductivity.
In their experiments, the team subjected the mushrooms to various voltage and frequency tests. Remarkably, the fungi demonstrated memristor-like behavior, maintaining effective performance for signals up to 5.85 kilohertz. While traditional materials can achieve higher frequencies, LaRocco noted that these results are impressive for biological materials. Additionally, shiitake mushrooms exhibit high levels of radiation resistance, making them suitable for applications in aerospace and medical fields.
LaRocco emphasized the environmental benefits of using shiitake, stating that the mushrooms are already commercially cultivated, which could support scalable production of organic memristors.
Honey’s Biodegradable Potential
In a separate study conducted at Washington State University, researchers examined whether honey could serve as a sustainable alternative in electronic applications. Led by Feng Zhao, the team aimed to address the e-waste crisis, which produces approximately 50 million tons annually, with only 20 percent recycled.
The researchers engineered a honey-based memristor by blending commercial honey with water and removing air bubbles through vacuum storage. They then applied the mixture onto copper, baked it, and capped it with circular copper electrodes. The resulting device demonstrated the ability to switch between resistance states in just 500 nanoseconds, comparable to some non-food-based memristors.
Zhao pointed out that honey’s widespread availability and low cost make it an attractive candidate for scalable production. Furthermore, honey is biodegradable, posing minimal environmental impact. However, the researchers acknowledged that to achieve full biodegradability, the copper components would need to be replaced with dissolvable metals, which is still under investigation.
Blood: The Human Memristor
An intriguing exploration into the potential for human blood as a memristor emerged from research conducted in India in 2011. The study, published in the International Journal of Medical Engineering and Informatics, involved filling a test tube with fresh type O+ human blood and connecting two conducting wire probes to create a circuit.
The researchers applied varying voltages to the blood and observed its resistance. They found that resistance changed minimally, by less than 10 percent, over a 30-minute period after voltage was applied. The results prompted the researchers to speculate that their setup could function as a “human blood memristor,” providing insights into potential healthcare applications.
These innovative studies showcase the remarkable adaptability of various materials in the field of electronics. As researchers continue to explore the properties of organic and unconventional substances, the future of memristor technology may be more diverse and sustainable than previously thought.
