Spike Narayan is a seasoned hi-tech executive managing exploratory research in science and technology at IBM.
The phrase “Sustainable Planet” is often used interchangeably with Climate Change and Greener Planet (and several other cliches) but at the heart of it are two fundamental issues namely rising planet temperatures and finite resources for the planet’s inhabitants.
These are not orthogonal issues as they have some common touch points but drive quite different streams of investigations and require vastly different skill sets to address the challenges. The issue of rising global temperatures is tied to the, now well-known, carbon footprint issues and the underlying greenhouse gas emissions while the issue of finite resources is simply one of dwindling supply and rising demand for everything from energy to water to food and the list goes on. The need for novel materials is at the core of some of the issues that plague our supply/demand balance and, therefore, our ability to create a sustainable lifestyle. This article seeks to shed some light on the importance of materials discovery and how it can address these pain points.
The sustainability topic has several facets, and this article will address some of them to give readers a flavor for the importance of materials science in protecting our planet. Let us begin with energy. This is a very nuanced subject as it ranges from energy production to transportation to industrial processes to name a few. The production of energy is the aspect that is most visible in the media and technologies like solar and wind and geothermal are some of them. If we were to take the solar example, the success and hence the cost of the technology hinges on the efficiency of conversion of sunlight to electrical energy. The efficiency of conversion today is limited to ~25% if we use the abundant and low-cost polycrystalline silicon technology and can exceed 40% for very specialized high cost materials that were developed for space applications. There is ample room to engineer new materials that have superior conversion efficiencies.
If we look at wind turbines, they use rare earth magnets for generating electricity from rotating wind turbines. These materials are mined from parts of the world that are geopolitically unstable. The urgency of finding alternate materials is paramount. Let us take a drive into the area of transportation of goods and people. There is a giant push to electrify transportation across the world with many car companies unveiling very aggressive plans to switch from our mostly liquid fuel-based cars of today to a mostly electric fleet in a decade. Volvo is the most aggressive with a full transition to EV planned by 2030. The big ask for such a dramatic transition is the batteries required to propel the cars. While today’s Li-ion batteries appear to fit the bill, they have several drawbacks starting with cost (>$150/Kilo-watt-Hour) as the number one issue.
We need to drive the cost down to <$50/KwH). This is not simply a scale up to drive down cost issue. The other limitations of batteries today being time to a full charge, flammability and reduced performance under extreme hot (Middle East, South East Asia) and cold (North America, Northern Europe) conditions. Materials innovation is needed to explore a) non-Lithium technologies for the electrodes, b) electrolytes that are not flammable and preferably not liquid and c) battery chemistries with superior kinetics to enable fast charging – ideally get a full charge in 5 minutes. Every one of the above is an interesting materials challenge.
The next energy topic is industrial energy use. According to the US Energy Information Administration more than 70% of the global energy produced is consumed by transportation and industrial sectors were fertilizer, cement, chemicals and metals being some of the largest consumers of energy. These chemical industries have huge unmet need for materials processing innovation. As an example, inventing new catalysts can make the nitrogen fixation reaction used for fertilizer production more energy-efficient and can also reduce thermal energy required for most chemical production by lowering the reaction temperature.
The next topic worth discussing is one water. As we know, water is the next oil and many experts believe the next geopolitical instability will likely be driven by access to water resources much like how access to oil is driving today’s flash points. For those of us living in the southwestern United States, water scarcity is already a reality where droughts and fires are the new normal. Many other parts of the global are already under tremendous water stress.
According to a UNICEF publication half of the world’s population could be living in areas facing water scarcity by as early as 2025. This report has other startling facts around water access. What then keeps us from producing more potable water? There are several factors in the mix ranging from a rising population and water needs to climate change making rainfall scarcer and more unreliable to high cost of producing potable water. The third, namely costly clean water is an area that can be addressed by materials innovation. There are several areas that can are currently being explored to mitigate this water stress. These include fresh water from sea water or wastewater and extracting water from humidity in the air to name a couple. Converting sea water to potable water is called desalination and is limited today by the reverse osmosis membrane technology which is ripe for novel membrane materials.
The cost of producing 1 cubic meter (~250 gallons) of drinking water from sea water is around $0.5 to $1.5 depending on the local electricity costs and is therefore not a viable option for the developing and under-developed countries which are disproportionally impacted by water scarcity. Cleaning wastewater and brackish water can also be revolutionized by novel membranes and can cost about half as much as desalination.
Finally extracting water from the air is already possible but at a rather high cost due to the cost of manufacturing nanostructured materials that are required to do this. A new class of materials called metal-organic-frameworks (MOFs) are under investigation that are characterized by very high surface area per unit weight which is the driver for the effectiveness of “condensing” water from air. The challenge is to bring the energy needed to produce 1 liter of water to below 100 WH and the cost of MOFs from more than $1000 per Kg to under $100 per Kg to enable meaningful scale-up and use.
The last topic I will touch on today is plastic pollution. Everyone is familiar with how our oceans and landfills are being inundated with plastic waste. This is because plastics do not readily disintegrate or decompose for decades. The biggest plastic-type that we must contend with is PET (polyethylene-terephthalate) which is what is used for bottled water and other beverages and foods. Materials research to chemical decompose PET is underway and is likely to be a major game-changer soon with innovation in organo-catalysts.
In summary, many of the global challenges we face today in the energy, water and waste that must be addressed to enable sustainable living are gated by innovating new materials that can revolutionize the journey to a better world. However, the process of materials research is very Edisonian today and often take 10 or more years to commercialize. We are in urgent need of new ways to speed up materials discovery and research is now underway at IBM to dramatically accelerate the materials discovery process by invoking computing of different forms. This can be a topic of another article.