Despite the pandemic, the year 2020 has proven to be an amazingly productive year for Jun Yao, an assistant professor in the Electrical and Computer Engineering (ECE) Department and an adjunct faculty member in the Biomedical Engineering Department. During 2020, his groundbreaking work on new biomaterials harvested from the humble microbe Geobacter has inspired articles in such renowned scientific journals as Nature, Nature Communications, and NanoResearch and subsequently stoked international media coverage in more than 50 outlets. Those include Science, The Science Times, The Engineer, Popular Science, Cosmos, Environmental Journal, The Weather Channel, and Phys.org.
As Yao explains, “All these articles are based on the same amazing biomaterial, feeding into the vision of developing future 'green' electronics based on biomaterials.” Working with these fabulous green biomaterials, Yao and his research associates are creating trailblazing devices to tackle some of the world’s most vital problems.
All this research on novel biomaterials also inspired the UMass Armstrong Fund for Science to award a two-year, $40,000 grant to Yao, Microbiology Professor Derek Lovley, and their interdisciplinary team to support one of their most promising discoveries. The multidisciplinary research team is developing a device, which uses a natural protein created by Geobacter, to generate electricity from moisture in the air. The Armstrong grant will support scaling up this invention for practical applications.
The new technology could have significant implications for the future of renewable energy, climate change, medicine, and more. Yao and Lovley call their device an “Air-gen,” or air-powered generator. It uses electrically conductive protein nanowires produced by Geobacter to connect to electrodes so electrical current is generated from water vapor.
More than 30 years ago, Lovley discovered Geobacter in river mud. Geobacter microbes grow hair-like protein filaments that function as tiny, natural “nanowires” to transfer charges for their nourishment and to communicate with other bacteria.
Now the researchers are using Geobacter’s nanowires for several revolutionary purposes, including Air-gen. As Yao describes Air-gen, “We are literally making electricity out of thin air. The Air-gen generates clean energy 24/7.” Lovley, who has developed many sustainable, biology-based, electronic materials such as the nanowires over the past three decades, says Air-gen “is the most amazing and exciting application of protein nanowires yet.”
In response to the international scientific reaction to Air-gen, Yao published an intimate, behind-the-scenes account of this groundbreaking research in the celebrated scientific journal Nature.
As Yao writes in Nature, “A new type of energy-harvesting device, based on protein nanowires from the microbe Geobacter, can generate a sustained power output by producing a moisture gradient across the nanowire film using natural humidity.”
Yao concludes that “The potential of this discovery can ‘be big,’ as environmental energy harvesting offers the promise of clean energy for self-sustained systems. Known technologies—such as solar cells, thermoelectric devices, and mechanical generators—all have specific environmental requirements that restrict where they can be deployed and limit their potential for continuous energy production.”
In contrast, says Yao, Air-gen employs atmospheric humidity, which can be viewed as a secondary form of solar energy and is “24/7 continuous and ubiquitous. Even the Sahara Desert has an average relative humidity of about 25 percent. The atmosphere contains water amount equivalent to 10 percent of total volume of fresh-water lakes in the world.”
In his Nature article, Yao concludes that Air-gen can “potentially address energy-related global issues such as providing a cheaper and easier means of electricity production in remote regions and poor countries.”
Beyond the Air-gen electricity that Yao and colleagues are generating, they are also conducting at least three very different, but closely related, research projects based on adaptations for Geobacter.
One involves electronics that can mimic the human brain in the efficient, biological learning known as neuromorphic computing, or computer functioning that can imitate the neuro-biological architectures of the human nervous system. Yao’s innovative research on neuromorphic computing promises to improve the efficiency of important computational tasks such as perception and decision making.
Only 10 years ago, scientists, working on what they hoped would open a new frontier of neuromorphic computing, could only dream of the kind of device created by Yao and Lovley. As described thoroughly in their Nature Communications paper, their research makes use of miniature tools called memristors, fabricated from the protein nanowires harvested from Geobacter, which function like real brain synapses.
This channel of research came about quite fortuitously in the midst of research to understand the protein nanowires used for Air-gen. That’s when Yao and Lovley discovered how to use these biological, electrical-conducting filaments to make a neuromorphic memristor, or “memory transistor” device, that runs very efficiently on extremely low power, as brains do, to carry signals between neurons and therefore function as human brain synapses do.
Another closely related research project concerns protein nanowires, harvested from Geobacter, from which Yao, Lovley, and collaborators have developed bioelectronic ammonia gas sensors that are among the most sensitive ever made, as described in the journal NanoResearch.
These finely tuned sensors use electric-charge-conducting protein nanowires to provide biomaterials for electrical devices.
Yao and Lovley say they designed this sensor to measure ammonia because this gas is important to agriculture, the environment, and biomedicine. For example, in humans, ammonia on the breath may signal disease, while, in poultry farming, the gas must be closely monitored and controlled for bird health and comfort and to avoid feed imbalances and production losses.
Yao is also the principal investigator on a very significant, $1,474,272 grant from the National Science Foundation, or NSF, based on more Geobacter-related research. Teaming Yao and Lovley once more, the NSF project is developing ultra-low-power electronic components and systems for signal retrieval, processing, and storage with power consumption similar to biological systems in living organisms, which require much less power than currently available in electronics manufactured by humans.
All this remarkably significant research is quickly establishing Yao as an important contributor in the field of green biomaterials that can be used to produce clean energy for self-sustaining systems, generate inexpensive electricity in economically strapped countries, help transform neuromorphic computing, develop bioelectric ammonia gas sensors, and much, much more.
While Yao is “making electricity out of thin air,” the sky is the limit. (October 2020)